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2024-04-30inet: introduce dst_rtable() helperGravatar Eric Dumazet 1-2/+1
I added dst_rt6_info() in commit e8dfd42c17fa ("ipv6: introduce dst_rt6_info() helper") This patch does a similar change for IPv4. Instead of (struct rtable *)dst casts, we can use : #define dst_rtable(_ptr) \ container_of_const(_ptr, struct rtable, dst) Patch is smaller than IPv6 one, because IPv4 has skb_rtable() helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://lore.kernel.org/r/20240429133009.1227754-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-29Merge tag 'for-netdev' of ↵Gravatar Jakub Kicinski 1-3/+12
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-04-29 We've added 147 non-merge commits during the last 32 day(s) which contain a total of 158 files changed, 9400 insertions(+), 2213 deletions(-). The main changes are: 1) Add an internal-only BPF per-CPU instruction for resolving per-CPU memory addresses and implement support in x86 BPF JIT. This allows inlining per-CPU array and hashmap lookups and the bpf_get_smp_processor_id() helper, from Andrii Nakryiko. 2) Add BPF link support for sk_msg and sk_skb programs, from Yonghong Song. 3) Optimize x86 BPF JIT's emit_mov_imm64, and add support for various atomics in bpf_arena which can be JITed as a single x86 instruction, from Alexei Starovoitov. 4) Add support for passing mark with bpf_fib_lookup helper, from Anton Protopopov. 5) Add a new bpf_wq API for deferring events and refactor sleepable bpf_timer code to keep common code where possible, from Benjamin Tissoires. 6) Fix BPF_PROG_TEST_RUN infra with regards to bpf_dummy_struct_ops programs to check when NULL is passed for non-NULLable parameters, from Eduard Zingerman. 7) Harden the BPF verifier's and/or/xor value tracking, from Harishankar Vishwanathan. 8) Introduce crypto kfuncs to make BPF programs able to utilize the kernel crypto subsystem, from Vadim Fedorenko. 9) Various improvements to the BPF instruction set standardization doc, from Dave Thaler. 10) Extend libbpf APIs to partially consume items from the BPF ringbuffer, from Andrea Righi. 11) Bigger batch of BPF selftests refactoring to use common network helpers and to drop duplicate code, from Geliang Tang. 12) Support bpf_tail_call_static() helper for BPF programs with GCC 13, from Jose E. Marchesi. 13) Add bpf_preempt_{disable,enable}() kfuncs in order to allow a BPF program to have code sections where preemption is disabled, from Kumar Kartikeya Dwivedi. 14) Allow invoking BPF kfuncs from BPF_PROG_TYPE_SYSCALL programs, from David Vernet. 15) Extend the BPF verifier to allow different input maps for a given bpf_for_each_map_elem() helper call in a BPF program, from Philo Lu. 16) Add support for PROBE_MEM32 and bpf_addr_space_cast instructions for riscv64 and arm64 JITs to enable BPF Arena, from Puranjay Mohan. 17) Shut up a false-positive KMSAN splat in interpreter mode by unpoison the stack memory, from Martin KaFai Lau. 18) Improve xsk selftest coverage with new tests on maximum and minimum hardware ring size configurations, from Tushar Vyavahare. 19) Various ReST man pages fixes as well as documentation and bash completion improvements for bpftool, from Rameez Rehman & Quentin Monnet. 20) Fix libbpf with regards to dumping subsequent char arrays, from Quentin Deslandes. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (147 commits) bpf, docs: Clarify PC use in instruction-set.rst bpf_helpers.h: Define bpf_tail_call_static when building with GCC bpf, docs: Add introduction for use in the ISA Internet Draft selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us bpf: add mrtt and srtt as BPF_SOCK_OPS_RTT_CB args selftests/bpf: dummy_st_ops should reject 0 for non-nullable params bpf: check bpf_dummy_struct_ops program params for test runs selftests/bpf: do not pass NULL for non-nullable params in dummy_st_ops selftests/bpf: adjust dummy_st_ops_success to detect additional error bpf: mark bpf_dummy_struct_ops.test_1 parameter as nullable selftests/bpf: Add ring_buffer__consume_n test. bpf: Add bpf_guard_preempt() convenience macro selftests: bpf: crypto: add benchmark for crypto functions selftests: bpf: crypto skcipher algo selftests bpf: crypto: add skcipher to bpf crypto bpf: make common crypto API for TC/XDP programs bpf: update the comment for BTF_FIELDS_MAX selftests/bpf: Fix wq test. selftests/bpf: Use make_sockaddr in test_sock_addr selftests/bpf: Use connect_to_addr in test_sock_addr ... ==================== Link: https://lore.kernel.org/r/20240429131657.19423-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-29ipv6: introduce dst_rt6_info() helperGravatar Eric Dumazet 1-1/+1
Instead of (struct rt6_info *)dst casts, we can use : #define dst_rt6_info(_ptr) \ container_of_const(_ptr, struct rt6_info, dst) Some places needed missing const qualifiers : ip6_confirm_neigh(), ipv6_anycast_destination(), ipv6_unicast_destination(), has_gateway() v2: added missing parts (David Ahern) Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-01ip_tunnel: convert __be16 tunnel flags to bitmapsGravatar Alexander Lobakin 1-12/+14
Historically, tunnel flags like TUNNEL_CSUM or TUNNEL_ERSPAN_OPT have been defined as __be16. Now all of those 16 bits are occupied and there's no more free space for new flags. It can't be simply switched to a bigger container with no adjustments to the values, since it's an explicit Endian storage, and on LE systems (__be16)0x0001 equals to (__be64)0x0001000000000000. We could probably define new 64-bit flags depending on the Endianness, i.e. (__be64)0x0001 on BE and (__be64)0x00010000... on LE, but that would introduce an Endianness dependency and spawn a ton of Sparse warnings. To mitigate them, all of those places which were adjusted with this change would be touched anyway, so why not define stuff properly if there's no choice. Define IP_TUNNEL_*_BIT counterparts as a bit number instead of the value already coded and a fistful of <16 <-> bitmap> converters and helpers. The two flags which have a different bit position are SIT_ISATAP_BIT and VTI_ISVTI_BIT, as they were defined not as __cpu_to_be16(), but as (__force __be16), i.e. had different positions on LE and BE. Now they both have strongly defined places. Change all __be16 fields which were used to store those flags, to IP_TUNNEL_DECLARE_FLAGS() -> DECLARE_BITMAP(__IP_TUNNEL_FLAG_NUM) -> unsigned long[1] for now, and replace all TUNNEL_* occurrences to their bitmap counterparts. Use the converters in the places which talk to the userspace, hardware (NFP) or other hosts (GRE header). The rest must explicitly use the new flags only. This must be done at once, otherwise there will be too many conversions throughout the code in the intermediate commits. Finally, disable the old __be16 flags for use in the kernel code (except for the two 'irregular' flags mentioned above), to prevent any accidental (mis)use of them. For the userspace, nothing is changed, only additions were made. Most noticeable bloat-o-meter difference (.text): vmlinux: 307/-1 (306) gre.ko: 62/0 (62) ip_gre.ko: 941/-217 (724) [*] ip_tunnel.ko: 390/-900 (-510) [**] ip_vti.ko: 138/0 (138) ip6_gre.ko: 534/-18 (516) [*] ip6_tunnel.ko: 118/-10 (108) [*] gre_flags_to_tnl_flags() grew, but still is inlined [**] ip_tunnel_find() got uninlined, hence such decrease The average code size increase in non-extreme case is 100-200 bytes per module, mostly due to sizeof(long) > sizeof(__be16), as %__IP_TUNNEL_FLAG_NUM is less than %BITS_PER_LONG and the compilers are able to expand the majority of bitmap_*() calls here into direct operations on scalars. Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-28bpf: Add a check for struct bpf_fib_lookup sizeGravatar Anton Protopopov 1-0/+3
The struct bpf_fib_lookup should not grow outside of its 64 bytes. Add a static assert to validate this. Suggested-by: David Ahern <dsahern@kernel.org> Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240326101742.17421-4-aspsk@isovalent.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-28bpf: Add support for passing mark with bpf_fib_lookupGravatar Anton Protopopov 1-3/+9
Extend the bpf_fib_lookup() helper by making it to utilize mark if the BPF_FIB_LOOKUP_MARK flag is set. In order to pass the mark the four bytes of struct bpf_fib_lookup are used, shared with the output-only smac/dmac fields. Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: David Ahern <dsahern@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240326101742.17421-2-aspsk@isovalent.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-19bpf: Allow helper bpf_get_[ns_]current_pid_tgid() for all prog typesGravatar Yonghong Song 1-2/+0
Currently bpf_get_current_pid_tgid() is allowed in tracing, cgroup and sk_msg progs while bpf_get_ns_current_pid_tgid() is only allowed in tracing progs. We have an internal use case where for an application running in a container (with pid namespace), user wants to get the pid associated with the pid namespace in a cgroup bpf program. Currently, cgroup bpf progs already allow bpf_get_current_pid_tgid(). Let us allow bpf_get_ns_current_pid_tgid() as well. With auditing the code, bpf_get_current_pid_tgid() is also used by sk_msg prog. But there are no side effect to expose these two helpers to all prog types since they do not reveal any kernel specific data. The detailed discussion is in [1]. So with this patch, both bpf_get_current_pid_tgid() and bpf_get_ns_current_pid_tgid() are put in bpf_base_func_proto(), making them available to all program types. [1] https://lore.kernel.org/bpf/20240307232659.1115872-1-yonghong.song@linux.dev/ Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20240315184854.2975190-1-yonghong.song@linux.dev
2024-03-02Merge tag 'for-netdev' of ↵Gravatar Jakub Kicinski 1-10/+10
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-02-29 We've added 119 non-merge commits during the last 32 day(s) which contain a total of 150 files changed, 3589 insertions(+), 995 deletions(-). The main changes are: 1) Extend the BPF verifier to enable static subprog calls in spin lock critical sections, from Kumar Kartikeya Dwivedi. 2) Fix confusing and incorrect inference of PTR_TO_CTX argument type in BPF global subprogs, from Andrii Nakryiko. 3) Larger batch of riscv BPF JIT improvements and enabling inlining of the bpf_kptr_xchg() for RV64, from Pu Lehui. 4) Allow skeleton users to change the values of the fields in struct_ops maps at runtime, from Kui-Feng Lee. 5) Extend the verifier's capabilities of tracking scalars when they are spilled to stack, especially when the spill or fill is narrowing, from Maxim Mikityanskiy & Eduard Zingerman. 6) Various BPF selftest improvements to fix errors under gcc BPF backend, from Jose E. Marchesi. 7) Avoid module loading failure when the module trying to register a struct_ops has its BTF section stripped, from Geliang Tang. 8) Annotate all kfuncs in .BTF_ids section which eventually allows for automatic kfunc prototype generation from bpftool, from Daniel Xu. 9) Several updates to the instruction-set.rst IETF standardization document, from Dave Thaler. 10) Shrink the size of struct bpf_map resp. bpf_array, from Alexei Starovoitov. 11) Initial small subset of BPF verifier prepwork for sleepable bpf_timer, from Benjamin Tissoires. 12) Fix bpftool to be more portable to musl libc by using POSIX's basename(), from Arnaldo Carvalho de Melo. 13) Add libbpf support to gcc in CORE macro definitions, from Cupertino Miranda. 14) Remove a duplicate type check in perf_event_bpf_event, from Florian Lehner. 15) Fix bpf_spin_{un,}lock BPF helpers to actually annotate them with notrace correctly, from Yonghong Song. 16) Replace the deprecated bpf_lpm_trie_key 0-length array with flexible array to fix build warnings, from Kees Cook. 17) Fix resolve_btfids cross-compilation to non host-native endianness, from Viktor Malik. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits) selftests/bpf: Test if shadow types work correctly. bpftool: Add an example for struct_ops map and shadow type. bpftool: Generated shadow variables for struct_ops maps. libbpf: Convert st_ops->data to shadow type. libbpf: Set btf_value_type_id of struct bpf_map for struct_ops. bpf: Replace bpf_lpm_trie_key 0-length array with flexible array bpf, arm64: use bpf_prog_pack for memory management arm64: patching: implement text_poke API bpf, arm64: support exceptions arm64: stacktrace: Implement arch_bpf_stack_walk() for the BPF JIT bpf: add is_async_callback_calling_insn() helper bpf: introduce in_sleepable() helper bpf: allow more maps in sleepable bpf programs selftests/bpf: Test case for lacking CFI stub functions. bpf: Check cfi_stubs before registering a struct_ops type. bpf: Clarify batch lookup/lookup_and_delete semantics bpf, docs: specify which BPF_ABS and BPF_IND fields were zero bpf, docs: Fix typos in instruction-set.rst selftests/bpf: update tcp_custom_syncookie to use scalar packet offset bpf: Shrink size of struct bpf_map/bpf_array. ... ==================== Link: https://lore.kernel.org/r/20240301001625.8800-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-01ipv6: annotate data-races around cnf.forwardingGravatar Eric Dumazet 1-1/+1
idev->cnf.forwarding and net->ipv6.devconf_all->forwarding might be read locklessly, add appropriate READ_ONCE() and WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-01-31bpf: treewide: Annotate BPF kfuncs in BTFGravatar Daniel Xu 1-10/+10
This commit marks kfuncs as such inside the .BTF_ids section. The upshot of these annotations is that we'll be able to automatically generate kfunc prototypes for downstream users. The process is as follows: 1. In source, use BTF_KFUNCS_START/END macro pair to mark kfuncs 2. During build, pahole injects into BTF a "bpf_kfunc" BTF_DECL_TAG for each function inside BTF_KFUNCS sets 3. At runtime, vmlinux or module BTF is made available in sysfs 4. At runtime, bpftool (or similar) can look at provided BTF and generate appropriate prototypes for functions with "bpf_kfunc" tag To ensure future kfunc are similarly tagged, we now also return error inside kfunc registration for untagged kfuncs. For vmlinux kfuncs, we also WARN(), as initcall machinery does not handle errors. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Acked-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/e55150ceecbf0a5d961e608941165c0bee7bc943.1706491398.git.dxu@dxuuu.xyz Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-26Merge tag 'for-netdev' of ↵Gravatar Jakub Kicinski 1-24/+131
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-01-26 We've added 107 non-merge commits during the last 4 day(s) which contain a total of 101 files changed, 6009 insertions(+), 1260 deletions(-). The main changes are: 1) Add BPF token support to delegate a subset of BPF subsystem functionality from privileged system-wide daemons such as systemd through special mount options for userns-bound BPF fs to a trusted & unprivileged application. With addressed changes from Christian and Linus' reviews, from Andrii Nakryiko. 2) Support registration of struct_ops types from modules which helps projects like fuse-bpf that seeks to implement a new struct_ops type, from Kui-Feng Lee. 3) Add support for retrieval of cookies for perf/kprobe multi links, from Jiri Olsa. 4) Bigger batch of prep-work for the BPF verifier to eventually support preserving boundaries and tracking scalars on narrowing fills, from Maxim Mikityanskiy. 5) Extend the tc BPF flavor to support arbitrary TCP SYN cookies to help with the scenario of SYN floods, from Kuniyuki Iwashima. 6) Add code generation to inline the bpf_kptr_xchg() helper which improves performance when stashing/popping the allocated BPF objects, from Hou Tao. 7) Extend BPF verifier to track aligned ST stores as imprecise spilled registers, from Yonghong Song. 8) Several fixes to BPF selftests around inline asm constraints and unsupported VLA code generation, from Jose E. Marchesi. 9) Various updates to the BPF IETF instruction set draft document such as the introduction of conformance groups for instructions, from Dave Thaler. 10) Fix BPF verifier to make infinite loop detection in is_state_visited() exact to catch some too lax spill/fill corner cases, from Eduard Zingerman. 11) Refactor the BPF verifier pointer ALU check to allow ALU explicitly instead of implicitly for various register types, from Hao Sun. 12) Fix the flaky tc_redirect_dtime BPF selftest due to slowness in neighbor advertisement at setup time, from Martin KaFai Lau. 13) Change BPF selftests to skip callback tests for the case when the JIT is disabled, from Tiezhu Yang. 14) Add a small extension to libbpf which allows to auto create a map-in-map's inner map, from Andrey Grafin. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (107 commits) selftests/bpf: Add missing line break in test_verifier bpf, docs: Clarify definitions of various instructions bpf: Fix error checks against bpf_get_btf_vmlinux(). bpf: One more maintainer for libbpf and BPF selftests selftests/bpf: Incorporate LSM policy to token-based tests selftests/bpf: Add tests for LIBBPF_BPF_TOKEN_PATH envvar libbpf: Support BPF token path setting through LIBBPF_BPF_TOKEN_PATH envvar selftests/bpf: Add tests for BPF object load with implicit token selftests/bpf: Add BPF object loading tests with explicit token passing libbpf: Wire up BPF token support at BPF object level libbpf: Wire up token_fd into feature probing logic libbpf: Move feature detection code into its own file libbpf: Further decouple feature checking logic from bpf_object libbpf: Split feature detectors definitions from cached results selftests/bpf: Utilize string values for delegate_xxx mount options bpf: Support symbolic BPF FS delegation mount options bpf: Fail BPF_TOKEN_CREATE if no delegation option was set on BPF FS bpf,selinux: Allocate bpf_security_struct per BPF token selftests/bpf: Add BPF token-enabled tests libbpf: Add BPF token support to bpf_prog_load() API ... ==================== Link: https://lore.kernel.org/r/20240126215710.19855-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-24xdp: reflect tail increase for MEM_TYPE_XSK_BUFF_POOLGravatar Maciej Fijalkowski 1-0/+2
XSK ZC Rx path calculates the size of data that will be posted to XSK Rx queue via subtracting xdp_buff::data_end from xdp_buff::data. In bpf_xdp_frags_increase_tail(), when underlying memory type of xdp_rxq_info is MEM_TYPE_XSK_BUFF_POOL, add offset to data_end in tail fragment, so that later on user space will be able to take into account the amount of bytes added by XDP program. Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX") Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/r/20240124191602.566724-10-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-24xsk: fix usage of multi-buffer BPF helpers for ZC XDPGravatar Maciej Fijalkowski 1-6/+36
Currently when packet is shrunk via bpf_xdp_adjust_tail() and memory type is set to MEM_TYPE_XSK_BUFF_POOL, null ptr dereference happens: [1136314.192256] BUG: kernel NULL pointer dereference, address: 0000000000000034 [1136314.203943] #PF: supervisor read access in kernel mode [1136314.213768] #PF: error_code(0x0000) - not-present page [1136314.223550] PGD 0 P4D 0 [1136314.230684] Oops: 0000 [#1] PREEMPT SMP NOPTI [1136314.239621] CPU: 8 PID: 54203 Comm: xdpsock Not tainted 6.6.0+ #257 [1136314.250469] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 [1136314.265615] RIP: 0010:__xdp_return+0x6c/0x210 [1136314.274653] Code: ad 00 48 8b 47 08 49 89 f8 a8 01 0f 85 9b 01 00 00 0f 1f 44 00 00 f0 41 ff 48 34 75 32 4c 89 c7 e9 79 cd 80 ff 83 fe 03 75 17 <f6> 41 34 01 0f 85 02 01 00 00 48 89 cf e9 22 cc 1e 00 e9 3d d2 86 [1136314.302907] RSP: 0018:ffffc900089f8db0 EFLAGS: 00010246 [1136314.312967] RAX: ffffc9003168aed0 RBX: ffff8881c3300000 RCX: 0000000000000000 [1136314.324953] RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffffc9003168c000 [1136314.336929] RBP: 0000000000000ae0 R08: 0000000000000002 R09: 0000000000010000 [1136314.348844] R10: ffffc9000e495000 R11: 0000000000000040 R12: 0000000000000001 [1136314.360706] R13: 0000000000000524 R14: ffffc9003168aec0 R15: 0000000000000001 [1136314.373298] FS: 00007f8df8bbcb80(0000) GS:ffff8897e0e00000(0000) knlGS:0000000000000000 [1136314.386105] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1136314.396532] CR2: 0000000000000034 CR3: 00000001aa912002 CR4: 00000000007706f0 [1136314.408377] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1136314.420173] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1136314.431890] PKRU: 55555554 [1136314.439143] Call Trace: [1136314.446058] <IRQ> [1136314.452465] ? __die+0x20/0x70 [1136314.459881] ? page_fault_oops+0x15b/0x440 [1136314.468305] ? exc_page_fault+0x6a/0x150 [1136314.476491] ? asm_exc_page_fault+0x22/0x30 [1136314.484927] ? __xdp_return+0x6c/0x210 [1136314.492863] bpf_xdp_adjust_tail+0x155/0x1d0 [1136314.501269] bpf_prog_ccc47ae29d3b6570_xdp_sock_prog+0x15/0x60 [1136314.511263] ice_clean_rx_irq_zc+0x206/0xc60 [ice] [1136314.520222] ? ice_xmit_zc+0x6e/0x150 [ice] [1136314.528506] ice_napi_poll+0x467/0x670 [ice] [1136314.536858] ? ttwu_do_activate.constprop.0+0x8f/0x1a0 [1136314.546010] __napi_poll+0x29/0x1b0 [1136314.553462] net_rx_action+0x133/0x270 [1136314.561619] __do_softirq+0xbe/0x28e [1136314.569303] do_softirq+0x3f/0x60 This comes from __xdp_return() call with xdp_buff argument passed as NULL which is supposed to be consumed by xsk_buff_free() call. To address this properly, in ZC case, a node that represents the frag being removed has to be pulled out of xskb_list. Introduce appropriate xsk helpers to do such node operation and use them accordingly within bpf_xdp_adjust_tail(). Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX") Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> # For the xsk header part Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/r/20240124191602.566724-4-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-24bpf: Consistently use BPF token throughout BPF verifier logicGravatar Andrii Nakryiko 1-2/+2
Remove remaining direct queries to perfmon_capable() and bpf_capable() in BPF verifier logic and instead use BPF token (if available) to make decisions about privileges. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-9-andrii@kernel.org
2024-01-24bpf: Take into account BPF token when fetching helper protosGravatar Andrii Nakryiko 1-16/+16
Instead of performing unconditional system-wide bpf_capable() and perfmon_capable() calls inside bpf_base_func_proto() function (and other similar ones) to determine eligibility of a given BPF helper for a given program, use previously recorded BPF token during BPF_PROG_LOAD command handling to inform the decision. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-8-andrii@kernel.org
2024-01-23bpf: tcp: Support arbitrary SYN Cookie.Gravatar Kuniyuki Iwashima 1-2/+109
This patch adds a new kfunc available at TC hook to support arbitrary SYN Cookie. The basic usage is as follows: struct bpf_tcp_req_attrs attrs = { .mss = mss, .wscale_ok = wscale_ok, .rcv_wscale = rcv_wscale, /* Server's WScale < 15 */ .snd_wscale = snd_wscale, /* Client's WScale < 15 */ .tstamp_ok = tstamp_ok, .rcv_tsval = tsval, .rcv_tsecr = tsecr, /* Server's Initial TSval */ .usec_ts_ok = usec_ts_ok, .sack_ok = sack_ok, .ecn_ok = ecn_ok, } skc = bpf_skc_lookup_tcp(...); sk = (struct sock *)bpf_skc_to_tcp_sock(skc); bpf_sk_assign_tcp_reqsk(skb, sk, attrs, sizeof(attrs)); bpf_sk_release(skc); bpf_sk_assign_tcp_reqsk() takes skb, a listener sk, and struct bpf_tcp_req_attrs and allocates reqsk and configures it. Then, bpf_sk_assign_tcp_reqsk() links reqsk with skb and the listener. The notable thing here is that we do not hold refcnt for both reqsk and listener. To differentiate that, we mark reqsk->syncookie, which is only used in TX for now. So, if reqsk->syncookie is 1 in RX, it means that the reqsk is allocated by kfunc. When skb is freed, sock_pfree() checks if reqsk->syncookie is 1, and in that case, we set NULL to reqsk->rsk_listener before calling reqsk_free() as reqsk does not hold a refcnt of the listener. When the TCP stack looks up a socket from the skb, we steal the listener from the reqsk in skb_steal_sock() and create a full sk in cookie_v[46]_check(). The refcnt of reqsk will finally be set to 1 in tcp_get_cookie_sock() after creating a full sk. Note that we can extend struct bpf_tcp_req_attrs in the future when we add a new attribute that is determined in 3WHS. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240115205514.68364-6-kuniyu@amazon.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-23net: filter: fix spelling mistakesGravatar Randy Dunlap 1-4/+4
Fix spelling errors as reported by codespell. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: bpf@vger.kernel.org Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240106065545.16855-1-rdunlap@infradead.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-19Revert BPF token-related functionalityGravatar Andrii Nakryiko 1-18/+18
This patch includes the following revert (one conflicting BPF FS patch and three token patch sets, represented by merge commits): - revert 0f5d5454c723 "Merge branch 'bpf-fs-mount-options-parsing-follow-ups'"; - revert 750e785796bb "bpf: Support uid and gid when mounting bpffs"; - revert 733763285acf "Merge branch 'bpf-token-support-in-libbpf-s-bpf-object'"; - revert c35919dcce28 "Merge branch 'bpf-token-and-bpf-fs-based-delegation'". Link: https://lore.kernel.org/bpf/CAHk-=wg7JuFYwGy=GOMbRCtOL+jwSQsdUaBsRWkDVYbxipbM5A@mail.gmail.com Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-12-19bpf: Use nla_ok() instead of checking nla_len directlyGravatar Jakub Kicinski 1-1/+1
nla_len may also be too short to be sane, in which case after recent changes nla_len() will return a wrapped value. Fixes: 172db56d90d2 ("netlink: Return unsigned value for nla_len()") Reported-by: syzbot+f43a23b6e622797c7a28@syzkaller.appspotmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/bpf/20231218231904.260440-1-kuba@kernel.org
2023-12-18Merge tag 'for-netdev' of ↵Gravatar Jakub Kicinski 1-18/+18
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Alexei Starovoitov says: ==================== pull-request: bpf-next 2023-12-18 This PR is larger than usual and contains changes in various parts of the kernel. The main changes are: 1) Fix kCFI bugs in BPF, from Peter Zijlstra. End result: all forms of indirect calls from BPF into kernel and from kernel into BPF work with CFI enabled. This allows BPF to work with CONFIG_FINEIBT=y. 2) Introduce BPF token object, from Andrii Nakryiko. It adds an ability to delegate a subset of BPF features from privileged daemon (e.g., systemd) through special mount options for userns-bound BPF FS to a trusted unprivileged application. The design accommodates suggestions from Christian Brauner and Paul Moore. Example: $ sudo mkdir -p /sys/fs/bpf/token $ sudo mount -t bpf bpffs /sys/fs/bpf/token \ -o delegate_cmds=prog_load:MAP_CREATE \ -o delegate_progs=kprobe \ -o delegate_attachs=xdp 3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei. - Complete precision tracking support for register spills - Fix verification of possibly-zero-sized stack accesses - Fix access to uninit stack slots - Track aligned STACK_ZERO cases as imprecise spilled registers. It improves the verifier "instructions processed" metric from single digit to 50-60% for some programs. - Fix verifier retval logic 4) Support for VLAN tag in XDP hints, from Larysa Zaremba. 5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu. End result: better memory utilization and lower I$ miss for calls to BPF via BPF trampoline. 6) Fix race between BPF prog accessing inner map and parallel delete, from Hou Tao. 7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu. It allows BPF interact with IPSEC infra. The intent is to support software RSS (via XDP) for the upcoming ipsec pcpu work. Experiments on AWS demonstrate single tunnel pcpu ipsec reaching line rate on 100G ENA nics. 8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao. 9) BPF file verification via fsverity, from Song Liu. It allows BPF progs get fsverity digest. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits) bpf: Ensure precise is reset to false in __mark_reg_const_zero() selftests/bpf: Add more uprobe multi fail tests bpf: Fail uprobe multi link with negative offset selftests/bpf: Test the release of map btf s390/bpf: Fix indirect trampoline generation selftests/bpf: Temporarily disable dummy_struct_ops test on s390 x86/cfi,bpf: Fix bpf_exception_cb() signature bpf: Fix dtor CFI cfi: Add CFI_NOSEAL() x86/cfi,bpf: Fix bpf_struct_ops CFI x86/cfi,bpf: Fix bpf_callback_t CFI x86/cfi,bpf: Fix BPF JIT call cfi: Flip headers selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment bpf: Limit the number of kprobes when attaching program to multiple kprobes bpf: Limit the number of uprobes when attaching program to multiple uprobes bpf: xdp: Register generic_kfunc_set with XDP programs selftests/bpf: utilize string values for delegate_xxx mount options ... ==================== Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-15net: Namespace-ify sysctl_optmem_maxGravatar Eric Dumazet 1-5/+7
optmem_max being used in tx zerocopy, we want to be able to control it on a netns basis. Following patch changes two tests. Tested: oqq130:~# cat /proc/sys/net/core/optmem_max 131072 oqq130:~# echo 1000000 >/proc/sys/net/core/optmem_max oqq130:~# cat /proc/sys/net/core/optmem_max 1000000 oqq130:~# unshare -n oqq130:~# cat /proc/sys/net/core/optmem_max 131072 oqq130:~# exit logout oqq130:~# cat /proc/sys/net/core/optmem_max 1000000 Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netGravatar Jakub Kicinski 1-0/+19
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/stmicro/stmmac/dwmac5.c drivers/net/ethernet/stmicro/stmmac/dwmac5.h drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c drivers/net/ethernet/stmicro/stmmac/hwif.h 37e4b8df27bc ("net: stmmac: fix FPE events losing") c3f3b97238f6 ("net: stmmac: Refactor EST implementation") https://lore.kernel.org/all/20231206110306.01e91114@canb.auug.org.au/ Adjacent changes: net/ipv4/tcp_ao.c 9396c4ee93f9 ("net/tcp: Don't store TCP-AO maclen on reqsk") 7b0f570f879a ("tcp: Move TCP-AO bits from cookie_v[46]_check() to tcp_ao_syncookie().") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-07bpf: sockmap, updating the sg structure should also update currGravatar John Fastabend 1-0/+19
Curr pointer should be updated when the sg structure is shifted. Fixes: 7246d8ed4dcce ("bpf: helper to pop data from messages") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20231206232706.374377-3-john.fastabend@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-06bpf: consistently use BPF token throughout BPF verifier logicGravatar Andrii Nakryiko 1-2/+2
Remove remaining direct queries to perfmon_capable() and bpf_capable() in BPF verifier logic and instead use BPF token (if available) to make decisions about privileges. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-06bpf: take into account BPF token when fetching helper protosGravatar Andrii Nakryiko 1-16/+16
Instead of performing unconditional system-wide bpf_capable() and perfmon_capable() calls inside bpf_base_func_proto() function (and other similar ones) to determine eligibility of a given BPF helper for a given program, use previously recorded BPF token during BPF_PROG_LOAD command handling to inform the decision. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-8-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-29tcp: Don't pass cookie to __cookie_v[46]_check().Gravatar Kuniyuki Iwashima 1-11/+4
tcp_hdr(skb) and SYN Cookie are passed to __cookie_v[46]_check(), but none of the callers passes cookie other than ntohl(th->ack_seq) - 1. Let's fetch it in __cookie_v[46]_check() instead of passing the cookie over and over. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20231129022924.96156-5-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-20bpf, netkit: Add indirect call wrapper for fetching peer devGravatar Daniel Borkmann 1-5/+13
ndo_get_peer_dev is used in tcx BPF fast path, therefore make use of indirect call wrapper and therefore optimize the bpf_redirect_peer() internal handling a bit. Add a small skb_get_peer_dev() wrapper which utilizes the INDIRECT_CALL_1() macro instead of open coding. Future work could potentially add a peer pointer directly into struct net_device in future and convert veth and netkit over to use it so that eventually ndo_get_peer_dev can be removed. Co-developed-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20231114004220.6495-7-daniel@iogearbox.net Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-11-20bpf: Fix dev's rx stats for bpf_redirect_peer trafficGravatar Peilin Ye 1-0/+1
Traffic redirected by bpf_redirect_peer() (used by recent CNIs like Cilium) is not accounted for in the RX stats of supported devices (that is, veth and netkit), confusing user space metrics collectors such as cAdvisor [0], as reported by Youlun. Fix it by calling dev_sw_netstats_rx_add() in skb_do_redirect(), to update RX traffic counters. Devices that support ndo_get_peer_dev _must_ use the @tstats per-CPU counters (instead of @lstats, or @dstats). To make this more fool-proof, error out when ndo_get_peer_dev is set but @tstats are not selected. [0] Specifically, the "container_network_receive_{byte,packet}s_total" counters are affected. Fixes: 9aa1206e8f48 ("bpf: Add redirect_peer helper") Reported-by: Youlun Zhang <zhangyoulun@bytedance.com> Signed-off-by: Peilin Ye <peilin.ye@bytedance.com> Co-developed-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/20231114004220.6495-6-daniel@iogearbox.net Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-11-01bpf: Add __bpf_kfunc_{start,end}_defs macrosGravatar Dave Marchevsky 1-9/+4
BPF kfuncs are meant to be called from BPF programs. Accordingly, most kfuncs are not called from anywhere in the kernel, which the -Wmissing-prototypes warning is unhappy about. We've peppered __diag_ignore_all("-Wmissing-prototypes", ... everywhere kfuncs are defined in the codebase to suppress this warning. This patch adds two macros meant to bound one or many kfunc definitions. All existing kfunc definitions which use these __diag calls to suppress -Wmissing-prototypes are migrated to use the newly-introduced macros. A new __diag_ignore_all - for "-Wmissing-declarations" - is added to the __bpf_kfunc_start_defs macro based on feedback from Andrii on an earlier version of this patch [0] and another recent mailing list thread [1]. In the future we might need to ignore different warnings or do other kfunc-specific things. This change will make it easier to make such modifications for all kfunc defs. [0]: https://lore.kernel.org/bpf/CAEf4BzaE5dRWtK6RPLnjTW-MW9sx9K3Fn6uwqCTChK2Dcb1Xig@mail.gmail.com/ [1]: https://lore.kernel.org/bpf/ZT+2qCc%2FaXep0%2FLf@krava/ Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Suggested-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Cc: Jiri Olsa <olsajiri@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: David Vernet <void@manifault.com> Acked-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20231031215625.2343848-1-davemarchevsky@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-10-17net, bpf: Add a warning if NAPI cb missed xdp_do_flush().Gravatar Sebastian Andrzej Siewior 1-0/+16
A few drivers were missing a xdp_do_flush() invocation after XDP_REDIRECT. Add three helper functions each for one of the per-CPU lists. Return true if the per-CPU list is non-empty and flush the list. Add xdp_do_check_flushed() which invokes each helper functions and creates a warning if one of the functions had a non-empty list. Hide everything behind CONFIG_DEBUG_NET. Suggested-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20231016125738.Yt79p1uF@linutronix.de
2023-10-11bpf: Implement cgroup sockaddr hooks for unix socketsGravatar Daan De Meyer 1-2/+12
These hooks allows intercepting connect(), getsockname(), getpeername(), sendmsg() and recvmsg() for unix sockets. The unix socket hooks get write access to the address length because the address length is not fixed when dealing with unix sockets and needs to be modified when a unix socket address is modified by the hook. Because abstract socket unix addresses start with a NUL byte, we cannot recalculate the socket address in kernelspace after running the hook by calculating the length of the unix socket path using strlen(). These hooks can be used when users want to multiplex syscall to a single unix socket to multiple different processes behind the scenes by redirecting the connect() and other syscalls to process specific sockets. We do not implement support for intercepting bind() because when using bind() with unix sockets with a pathname address, this creates an inode in the filesystem which must be cleaned up. If we rewrite the address, the user might try to clean up the wrong file, leaking the socket in the filesystem where it is never cleaned up. Until we figure out a solution for this (and a use case for intercepting bind()), we opt to not allow rewriting the sockaddr in bind() calls. We also implement recvmsg() support for connected streams so that after a connect() that is modified by a sockaddr hook, any corresponding recmvsg() on the connected socket can also be modified to make the connected program think it is connected to the "intended" remote. Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com> Link: https://lore.kernel.org/r/20231011185113.140426-5-daan.j.demeyer@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11bpf: Add bpf_sock_addr_set_sun_path() to allow writing unix sockaddr from bpfGravatar Daan De Meyer 1-1/+34
As prep for adding unix socket support to the cgroup sockaddr hooks, let's add a kfunc bpf_sock_addr_set_sun_path() that allows modifying a unix sockaddr from bpf. While this is already possible for AF_INET and AF_INET6, we'll need this kfunc when we add unix socket support since modifying the address for those requires modifying both the address and the sockaddr length. Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com> Link: https://lore.kernel.org/r/20231011185113.140426-4-daan.j.demeyer@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-09bpf: Derive source IP addr via bpf_*_fib_lookup()Gravatar Martynas Pumputis 1-1/+17
Extend the bpf_fib_lookup() helper by making it to return the source IPv4/IPv6 address if the BPF_FIB_LOOKUP_SRC flag is set. For example, the following snippet can be used to derive the desired source IP address: struct bpf_fib_lookup p = { .ipv4_dst = ip4->daddr }; ret = bpf_skb_fib_lookup(skb, p, sizeof(p), BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH); if (ret != BPF_FIB_LKUP_RET_SUCCESS) return TC_ACT_SHOT; /* the p.ipv4_src now contains the source address */ The inability to derive the proper source address may cause malfunctions in BPF-based dataplanes for hosts containing netdevs with more than one routable IP address or for multi-homed hosts. For example, Cilium implements packet masquerading in BPF. If an egressing netdev to which the Cilium's BPF prog is attached has multiple IP addresses, then only one [hardcoded] IP address can be used for masquerading. This breaks connectivity if any other IP address should have been selected instead, for example, when a public and private addresses are attached to the same egress interface. The change was tested with Cilium [1]. Nikolay Aleksandrov helped to figure out the IPv6 addr selection. [1]: https://github.com/cilium/cilium/pull/28283 Signed-off-by: Martynas Pumputis <m@lambda.lt> Link: https://lore.kernel.org/r/20231007081415.33502-2-m@lambda.lt Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-08-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netGravatar Jakub Kicinski 1-6/+0
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/intel/igc/igc_main.c 06b412589eef ("igc: Add lock to safeguard global Qbv variables") d3750076d464 ("igc: Add TransmissionOverrun counter") drivers/net/ethernet/microsoft/mana/mana_en.c a7dfeda6fdec ("net: mana: Fix MANA VF unload when hardware is unresponsive") a9ca9f9ceff3 ("page_pool: split types and declarations from page_pool.h") 92272ec4107e ("eth: add missing xdp.h includes in drivers") net/mptcp/protocol.h 511b90e39250 ("mptcp: fix disconnect vs accept race") b8dc6d6ce931 ("mptcp: fix rcv buffer auto-tuning") tools/testing/selftests/net/mptcp/mptcp_join.sh c8c101ae390a ("selftests: mptcp: join: fix 'implicit EP' test") 03668c65d153 ("selftests: mptcp: join: rework detailed report") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-07net: core: remove unnecessary frame_sz check in bpf_xdp_adjust_tail()Gravatar Andrew Kanner 1-6/+0
Syzkaller reported the following issue: ======================================= Too BIG xdp->frame_sz = 131072 WARNING: CPU: 0 PID: 5020 at net/core/filter.c:4121 ____bpf_xdp_adjust_tail net/core/filter.c:4121 [inline] WARNING: CPU: 0 PID: 5020 at net/core/filter.c:4121 bpf_xdp_adjust_tail+0x466/0xa10 net/core/filter.c:4103 ... Call Trace: <TASK> bpf_prog_4add87e5301a4105+0x1a/0x1c __bpf_prog_run include/linux/filter.h:600 [inline] bpf_prog_run_xdp include/linux/filter.h:775 [inline] bpf_prog_run_generic_xdp+0x57e/0x11e0 net/core/dev.c:4721 netif_receive_generic_xdp net/core/dev.c:4807 [inline] do_xdp_generic+0x35c/0x770 net/core/dev.c:4866 tun_get_user+0x2340/0x3ca0 drivers/net/tun.c:1919 tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2043 call_write_iter include/linux/fs.h:1871 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x650/0xe40 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd xdp->frame_sz > PAGE_SIZE check was introduced in commit c8741e2bfe87 ("xdp: Allow bpf_xdp_adjust_tail() to grow packet size"). But Jesper Dangaard Brouer <jbrouer@redhat.com> noted that after introducing the xdp_init_buff() which all XDP driver use - it's safe to remove this check. The original intend was to catch cases where XDP drivers have not been updated to use xdp.frame_sz, but that is not longer a concern (since xdp_init_buff). Running the initial syzkaller repro it was discovered that the contiguous physical memory allocation is used for both xdp paths in tun_get_user(), e.g. tun_build_skb() and tun_alloc_skb(). It was also stated by Jesper Dangaard Brouer <jbrouer@redhat.com> that XDP can work on higher order pages, as long as this is contiguous physical memory (e.g. a page). Reported-and-tested-by: syzbot+f817490f5bd20541b90a@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/000000000000774b9205f1d8a80d@google.com/T/ Link: https://syzkaller.appspot.com/bug?extid=f817490f5bd20541b90a Link: https://lore.kernel.org/all/20230725155403.796-1-andrew.kanner@gmail.com/T/ Fixes: 43b5169d8355 ("net, xdp: Introduce xdp_init_buff utility routine") Signed-off-by: Andrew Kanner <andrew.kanner@gmail.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Acked-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20230803190316.2380231-1-andrew.kanner@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-25bpf, net: Support SO_REUSEPORT sockets with bpf_sk_assignGravatar Lorenz Bauer 1-2/+0
Currently the bpf_sk_assign helper in tc BPF context refuses SO_REUSEPORT sockets. This means we can't use the helper to steer traffic to Envoy, which configures SO_REUSEPORT on its sockets. In turn, we're blocked from removing TPROXY from our setup. The reason that bpf_sk_assign refuses such sockets is that the bpf_sk_lookup helpers don't execute SK_REUSEPORT programs. Instead, one of the reuseport sockets is selected by hash. This could cause dispatch to the "wrong" socket: sk = bpf_sk_lookup_tcp(...) // select SO_REUSEPORT by hash bpf_sk_assign(skb, sk) // SK_REUSEPORT wasn't executed Fixing this isn't as simple as invoking SK_REUSEPORT from the lookup helpers unfortunately. In the tc context, L2 headers are at the start of the skb, while SK_REUSEPORT expects L3 headers instead. Instead, we execute the SK_REUSEPORT program when the assigned socket is pulled out of the skb, further up the stack. This creates some trickiness with regards to refcounting as bpf_sk_assign will put both refcounted and RCU freed sockets in skb->sk. reuseport sockets are RCU freed. We can infer that the sk_assigned socket is RCU freed if the reuseport lookup succeeds, but convincing yourself of this fact isn't straight forward. Therefore we defensively check refcounting on the sk_assign sock even though it's probably not required in practice. Fixes: 8e368dc72e86 ("bpf: Fix use of sk->sk_reuseport from sk_assign") Fixes: cf7fbe660f2d ("bpf: Add socket assign support") Co-developed-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Joe Stringer <joe@cilium.io> Link: https://lore.kernel.org/bpf/CACAyw98+qycmpQzKupquhkxbvWK4OFyDuuLMBNROnfWMZxUWeA@mail.gmail.com/ Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Lorenz Bauer <lmb@isovalent.com> Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-7-7021b683cdae@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-07-25bpf: reject unhashed sockets in bpf_sk_assignGravatar Lorenz Bauer 1-0/+2
The semantics for bpf_sk_assign are as follows: sk = some_lookup_func() bpf_sk_assign(skb, sk) bpf_sk_release(sk) That is, the sk is not consumed by bpf_sk_assign. The function therefore needs to make sure that sk lives long enough to be consumed from __inet_lookup_skb. The path through the stack for a TCPv4 packet is roughly: netif_receive_skb_core: takes RCU read lock __netif_receive_skb_core: sch_handle_ingress: tcf_classify: bpf_sk_assign() deliver_ptype_list_skb: deliver_skb: ip_packet_type->func == ip_rcv: ip_rcv_core: ip_rcv_finish_core: dst_input: ip_local_deliver: ip_local_deliver_finish: ip_protocol_deliver_rcu: tcp_v4_rcv: __inet_lookup_skb: skb_steal_sock The existing helper takes advantage of the fact that everything happens in the same RCU critical section: for sockets with SOCK_RCU_FREE set bpf_sk_assign never takes a reference. skb_steal_sock then checks SOCK_RCU_FREE again and does sock_put if necessary. This approach assumes that SOCK_RCU_FREE is never set on a sk between bpf_sk_assign and skb_steal_sock, but this invariant is violated by unhashed UDP sockets. A new UDP socket is created in TCP_CLOSE state but without SOCK_RCU_FREE set. That flag is only added in udp_lib_get_port() which happens when a socket is bound. When bpf_sk_assign was added it wasn't possible to access unhashed UDP sockets from BPF, so this wasn't a problem. This changed in commit 0c48eefae712 ("sock_map: Lift socket state restriction for datagram sockets"), but the helper wasn't adjusted accordingly. The following sequence of events will therefore lead to a refcount leak: 1. Add socket(AF_INET, SOCK_DGRAM) to a sockmap. 2. Pull socket out of sockmap and bpf_sk_assign it. Since SOCK_RCU_FREE is not set we increment the refcount. 3. bind() or connect() the socket, setting SOCK_RCU_FREE. 4. skb_steal_sock will now set refcounted = false due to SOCK_RCU_FREE. 5. tcp_v4_rcv() skips sock_put(). Fix the problem by rejecting unhashed sockets in bpf_sk_assign(). This matches the behaviour of __inet_lookup_skb which is ultimately the goal of bpf_sk_assign(). Fixes: cf7fbe660f2d ("bpf: Add socket assign support") Cc: Joe Stringer <joe@cilium.io> Signed-off-by: Lorenz Bauer <lmb@isovalent.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-2-7021b683cdae@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-07-19bpf: Add fd-based tcx multi-prog infra with link supportGravatar Daniel Borkmann 1-2/+2
This work refactors and adds a lightweight extension ("tcx") to the tc BPF ingress and egress data path side for allowing BPF program management based on fds via bpf() syscall through the newly added generic multi-prog API. The main goal behind this work which we also presented at LPC [0] last year and a recent update at LSF/MM/BPF this year [3] is to support long-awaited BPF link functionality for tc BPF programs, which allows for a model of safe ownership and program detachment. Given the rise in tc BPF users in cloud native environments, this becomes necessary to avoid hard to debug incidents either through stale leftover programs or 3rd party applications accidentally stepping on each others toes. As a recap, a BPF link represents the attachment of a BPF program to a BPF hook point. The BPF link holds a single reference to keep BPF program alive. Moreover, hook points do not reference a BPF link, only the application's fd or pinning does. A BPF link holds meta-data specific to attachment and implements operations for link creation, (atomic) BPF program update, detachment and introspection. The motivation for BPF links for tc BPF programs is multi-fold, for example: - From Meta: "It's especially important for applications that are deployed fleet-wide and that don't "control" hosts they are deployed to. If such application crashes and no one notices and does anything about that, BPF program will keep running draining resources or even just, say, dropping packets. We at FB had outages due to such permanent BPF attachment semantics. With fd-based BPF link we are getting a framework, which allows safe, auto-detachable behavior by default, unless application explicitly opts in by pinning the BPF link." [1] - From Cilium-side the tc BPF programs we attach to host-facing veth devices and phys devices build the core datapath for Kubernetes Pods, and they implement forwarding, load-balancing, policy, EDT-management, etc, within BPF. Currently there is no concept of 'safe' ownership, e.g. we've recently experienced hard-to-debug issues in a user's staging environment where another Kubernetes application using tc BPF attached to the same prio/handle of cls_bpf, accidentally wiping all Cilium-based BPF programs from underneath it. The goal is to establish a clear/safe ownership model via links which cannot accidentally be overridden. [0,2] BPF links for tc can co-exist with non-link attachments, and the semantics are in line also with XDP links: BPF links cannot replace other BPF links, BPF links cannot replace non-BPF links, non-BPF links cannot replace BPF links and lastly only non-BPF links can replace non-BPF links. In case of Cilium, this would solve mentioned issue of safe ownership model as 3rd party applications would not be able to accidentally wipe Cilium programs, even if they are not BPF link aware. Earlier attempts [4] have tried to integrate BPF links into core tc machinery to solve cls_bpf, which has been intrusive to the generic tc kernel API with extensions only specific to cls_bpf and suboptimal/complex since cls_bpf could be wiped from the qdisc also. Locking a tc BPF program in place this way, is getting into layering hacks given the two object models are vastly different. We instead implemented the tcx (tc 'express') layer which is an fd-based tc BPF attach API, so that the BPF link implementation blends in naturally similar to other link types which are fd-based and without the need for changing core tc internal APIs. BPF programs for tc can then be successively migrated from classic cls_bpf to the new tc BPF link without needing to change the program's source code, just the BPF loader mechanics for attaching is sufficient. For the current tc framework, there is no change in behavior with this change and neither does this change touch on tc core kernel APIs. The gist of this patch is that the ingress and egress hook have a lightweight, qdisc-less extension for BPF to attach its tc BPF programs, in other words, a minimal entry point for tc BPF. The name tcx has been suggested from discussion of earlier revisions of this work as a good fit, and to more easily differ between the classic cls_bpf attachment and the fd-based one. For the ingress and egress tcx points, the device holds a cache-friendly array with program pointers which is separated from control plane (slow-path) data. Earlier versions of this work used priority to determine ordering and expression of dependencies similar as with classic tc, but it was challenged that for something more future-proof a better user experience is required. Hence this resulted in the design and development of the generic attach/detach/query API for multi-progs. See prior patch with its discussion on the API design. tcx is the first user and later we plan to integrate also others, for example, one candidate is multi-prog support for XDP which would benefit and have the same 'look and feel' from API perspective. The goal with tcx is to have maximum compatibility to existing tc BPF programs, so they don't need to be rewritten specifically. Compatibility to call into classic tcf_classify() is also provided in order to allow successive migration or both to cleanly co-exist where needed given its all one logical tc layer and the tcx plus classic tc cls/act build one logical overall processing pipeline. tcx supports the simplified return codes TCX_NEXT which is non-terminating (go to next program) and terminating ones with TCX_PASS, TCX_DROP, TCX_REDIRECT. The fd-based API is behind a static key, so that when unused the code is also not entered. The struct tcx_entry's program array is currently static, but could be made dynamic if necessary at a point in future. The a/b pair swap design has been chosen so that for detachment there are no allocations which otherwise could fail. The work has been tested with tc-testing selftest suite which all passes, as well as the tc BPF tests from the BPF CI, and also with Cilium's L4LB. Thanks also to Nikolay Aleksandrov and Martin Lau for in-depth early reviews of this work. [0] https://lpc.events/event/16/contributions/1353/ [1] https://lore.kernel.org/bpf/CAEf4BzbokCJN33Nw_kg82sO=xppXnKWEncGTWCTB9vGCmLB6pw@mail.gmail.com [2] https://colocatedeventseu2023.sched.com/event/1Jo6O/tales-from-an-ebpf-programs-murder-mystery-hemanth-malla-guillaume-fournier-datadog [3] http://vger.kernel.org/bpfconf2023_material/tcx_meta_netdev_borkmann.pdf [4] https://lore.kernel.org/bpf/20210604063116.234316-1-memxor@gmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20230719140858.13224-3-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-19xsk: add support for AF_XDP multi-buffer on Rx pathGravatar Tirthendu Sarkar 1-6/+1
Add multi-buffer support for AF_XDP by extending the XDP multi-buffer support to be reflected in user-space when a packet is redirected to an AF_XDP socket. In the XDP implementation, the NIC driver builds the xdp_buff from the first frag of the packet and adds any subsequent frags in the skb_shinfo area of the xdp_buff. In AF_XDP core, XDP buffers are allocated from xdp_sock's pool and data is copied from the driver's xdp_buff and frags. Once an allocated XDP buffer is full and there is still data to be copied, the 'XDP_PKT_CONTD' flag in'options' field of the corresponding xdp ring descriptor is set and passed to the application. When application sees the aforementioned flag set it knows there is pending data for this packet that will be carried in the following descriptors. If there is no more data to be copied, the flag in 'options' field is cleared for that descriptor signalling EOP to the application. If application reads a batch of descriptors using for example the libxdp interfaces, it is not guaranteed that the batch will end with a full packet. It might end in the middle of a packet and the rest of the frames of that packet will arrive at the beginning of the next batch. AF_XDP ensures that only a complete packet (along with all its frags) is sent to application. Signed-off-by: Tirthendu Sarkar <tirthendu.sarkar@intel.com> Link: https://lore.kernel.org/r/20230719132421.584801-6-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-21bpf: Fix bpf socket lookup from tc/xdp to respect socket VRF bindingsGravatar Gilad Sever 1-30/+39
When calling bpf_sk_lookup_tcp(), bpf_sk_lookup_udp() or bpf_skc_lookup_tcp() from tc/xdp ingress, VRF socket bindings aren't respoected, i.e. unbound sockets are returned, and bound sockets aren't found. VRF binding is determined by the sdif argument to sk_lookup(), however when called from tc the IP SKB control block isn't initialized and thus inet{,6}_sdif() always returns 0. Fix by calculating sdif for the tc/xdp flows by observing the device's l3 enslaved state. The cg/sk_skb hooking points which are expected to support inet{,6}_sdif() pass sdif=-1 which makes __bpf_skc_lookup() use the existing logic. Fixes: 6acc9b432e67 ("bpf: Add helper to retrieve socket in BPF") Signed-off-by: Gilad Sever <gilad9366@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Reviewed-by: Eyal Birger <eyal.birger@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Cc: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/bpf/20230621104211.301902-4-gilad9366@gmail.com
2023-06-21bpf: Call __bpf_sk_lookup()/__bpf_skc_lookup() directly via TC hookpointGravatar Gilad Sever 1-6/+18
skb->dev always exists in the tc flow. There is no need to use bpf_skc_lookup(), bpf_sk_lookup() from this code path. This change facilitates fixing the tc flow to be VRF aware. Signed-off-by: Gilad Sever <gilad9366@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Reviewed-by: Eyal Birger <eyal.birger@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20230621104211.301902-3-gilad9366@gmail.com
2023-06-21bpf: Factor out socket lookup functions for the TC hookpoint.Gravatar Gilad Sever 1-3/+60
Change BPF helper socket lookup functions to use TC specific variants: bpf_tc_sk_lookup_tcp() / bpf_tc_sk_lookup_udp() / bpf_tc_skc_lookup_tcp() instead of sharing implementation with the cg / sk_skb hooking points. This allows introducing a separate logic for the TC flow. The tc functions are identical to the original code. Signed-off-by: Gilad Sever <gilad9366@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Reviewed-by: Eyal Birger <eyal.birger@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20230621104211.301902-2-gilad9366@gmail.com
2023-06-05bpf/xdp: optimize bpf_xdp_pointer to avoid reading sinfoGravatar Jesper Dangaard Brouer 1-3/+4
Currently we observed a significant performance degradation in samples/bpf xdp1 and xdp2, due XDP multibuffer "xdp.frags" handling, added in commit 772251742262 ("samples/bpf: fixup some tools to be able to support xdp multibuffer"). This patch reduce the overhead by avoiding to read/load shared_info (sinfo) memory area, when XDP packet don't have any frags. This improves performance because sinfo is located in another cacheline. Function bpf_xdp_pointer() is used by BPF helpers bpf_xdp_load_bytes() and bpf_xdp_store_bytes(). As a help to reviewers, xdp_get_buff_len() can potentially access sinfo, but it uses xdp_buff_has_frags() flags bit check to avoid accessing sinfo in no-frags case. The likely/unlikely instrumentation lays out asm code such that sinfo access isn't interleaved with no-frags case (checked on GCC 12.2.1-4). The generated asm code is more compact towards the no-frags case. The BPF kfunc bpf_dynptr_slice() also use bpf_xdp_pointer(). Thus, it should also take effect for that. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Lorenzo Bianconi <lorenzo@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/168563651438.3436004.17735707525651776648.stgit@firesoul Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-01bpf: Add table ID to bpf_fib_lookup BPF helperGravatar Louis DeLosSantos 1-1/+13
Add ability to specify routing table ID to the `bpf_fib_lookup` BPF helper. A new field `tbid` is added to `struct bpf_fib_lookup` used as parameters to the `bpf_fib_lookup` BPF helper. When the helper is called with the `BPF_FIB_LOOKUP_DIRECT` and `BPF_FIB_LOOKUP_TBID` flags the `tbid` field in `struct bpf_fib_lookup` will be used as the table ID for the fib lookup. If the `tbid` does not exist the fib lookup will fail with `BPF_FIB_LKUP_RET_NOT_FWDED`. The `tbid` field becomes a union over the vlan related output fields in `struct bpf_fib_lookup` and will be zeroed immediately after usage. This functionality is useful in containerized environments. For instance, if a CNI wants to dictate the next-hop for traffic leaving a container it can create a container-specific routing table and perform a fib lookup against this table in a "host-net-namespace-side" TC program. This functionality also allows `ip rule` like functionality at the TC layer, allowing an eBPF program to pick a routing table based on some aspect of the sk_buff. As a concrete use case, this feature will be used in Cilium's SRv6 L3VPN datapath. When egress traffic leaves a Pod an eBPF program attached by Cilium will determine which VRF the egress traffic should target, and then perform a FIB lookup in a specific table representing this VRF's FIB. Signed-off-by: Louis DeLosSantos <louis.delos.devel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230505-bpf-add-tbid-fib-lookup-v2-1-0a31c22c748c@gmail.com
2023-05-19bpf: Add bpf_sock_destroy kfuncGravatar Aditi Ghag 1-0/+63
The socket destroy kfunc is used to forcefully terminate sockets from certain BPF contexts. We plan to use the capability in Cilium load-balancing to terminate client sockets that continue to connect to deleted backends. The other use case is on-the-fly policy enforcement where existing socket connections prevented by policies need to be forcefully terminated. The kfunc also allows terminating sockets that may or may not be actively sending traffic. The kfunc can currently be called only from BPF TCP and UDP iterators where users can filter, and terminate selected sockets. More specifically, it can only be called from BPF contexts that ensure socket locking in order to allow synchronous execution of protocol specific `diag_destroy` handlers. The previous commit that batches UDP sockets during iteration facilitated a synchronous invocation of the UDP destroy callback from BPF context by skipping socket locks in `udp_abort`. TCP iterator already supported batching of sockets being iterated. To that end, `tracing_iter_filter` callback filter is added so that verifier can restrict the kfunc to programs with `BPF_TRACE_ITER` attach type, and reject other programs. The kfunc takes `sock_common` type argument, even though it expects, and casts them to a `sock` pointer. This enables the verifier to allow the sock_destroy kfunc to be called for TCP with `sock_common` and UDP with `sock` structs. Furthermore, as `sock_common` only has a subset of certain fields of `sock`, casting pointer to the latter type might not always be safe for certain sockets like request sockets, but these have a special handling in the diag_destroy handlers. Additionally, the kfunc is defined with `KF_TRUSTED_ARGS` flag to avoid the cases where a `PTR_TO_BTF_ID` sk is obtained by following another pointer. eg. getting a sk pointer (may be even NULL) by following another sk pointer. The pointer socket argument passed in TCP and UDP iterators is tagged as `PTR_TRUSTED` in {tcp,udp}_reg_info. The TRUSTED arg changes are contributed by Martin KaFai Lau <martin.lau@kernel.org>. Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-8-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-02bpf: Emit struct bpf_tcp_sock type in vmlinux BTFGravatar Yonghong Song 1-0/+2
In one of our internal testing, we found a case where - uapi struct bpf_tcp_sock is in vmlinux.h where vmlinux.h is not generated from the testing kernel - struct bpf_tcp_sock is not in vmlinux BTF The above combination caused bpf load failure as the following memory access struct bpf_tcp_sock *tcp_sock = ...; ... tcp_sock->snd_cwnd ... needs CORE relocation but the relocation cannot be resolved since the kernel BTF does not have corresponding type. Similar to other previous cases (nf_conn___init, tcp6_sock, mctcp_sock, etc.), add the type to vmlinux BTF with BTF_EMIT_TYPE macro. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230502180543.1832140-1-yhs@fb.com
2023-04-21bpf: minimal support for programs hooked into netfilter frameworkGravatar Florian Westphal 1-0/+1
This adds minimal support for BPF_PROG_TYPE_NETFILTER bpf programs that will be invoked via the NF_HOOK() points in the ip stack. Invocation incurs an indirect call. This is not a necessity: Its possible to add 'DEFINE_BPF_DISPATCHER(nf_progs)' and handle the program invocation with the same method already done for xdp progs. This isn't done here to keep the size of this chunk down. Verifier restricts verdicts to either DROP or ACCEPT. Signed-off-by: Florian Westphal <fw@strlen.de> Link: https://lore.kernel.org/r/20230421170300.24115-3-fw@strlen.de Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-17bpf: Set skb redirect and from_ingress info in __bpf_tx_skbGravatar Daniel Borkmann 1-0/+1
There are some use-cases where it is desirable to use bpf_redirect() in combination with ifb device, which currently is not supported, for example, around filtering inbound traffic with BPF to then push it to ifb which holds the qdisc for shaping in contrast to doing that on the egress device. Toke mentions the following case related to OpenWrt: Because there's not always a single egress on the other side. These are mainly home routers, which tend to have one or more WiFi devices bridged to one or more ethernet ports on the LAN side, and a single upstream WAN port. And the objective is to control the total amount of traffic going over the WAN link (in both directions), to deal with bufferbloat in the ISP network (which is sadly still all too prevalent). In this setup, the traffic can be split arbitrarily between the links on the LAN side, and the only "single bottleneck" is the WAN link. So we install both egress and ingress shapers on this, configured to something like 95-98% of the true link bandwidth, thus moving the queues into the qdisc layer in the router. It's usually necessary to set the ingress bandwidth shaper a bit lower than the egress due to being "downstream" of the bottleneck link, but it does work surprisingly well. We usually use something like a matchall filter to put all ingress traffic on the ifb, so doing the redirect from BPF has not been an immediate requirement thus far. However, it does seem a bit odd that this is not possible, and we do have a BPF-based filter that layers on top of this kind of setup, which currently uses u32 as the ingress filter and so it could presumably be improved to use BPF instead if that was available. Reported-by: Toke Høiland-Jørgensen <toke@redhat.com> Reported-by: Yafang Shao <laoar.shao@gmail.com> Reported-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://git.openwrt.org/?p=project/qosify.git;a=blob;f=README Link: https://lore.kernel.org/bpf/875y9yzbuy.fsf@toke.dk Link: https://lore.kernel.org/r/8cebc8b2b6e967e10cbafe2ffd6795050e74accd.1681739137.git.daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-13Daniel Borkmann says:Gravatar Jakub Kicinski 1-19/+10
==================== pull-request: bpf-next 2023-04-13 We've added 260 non-merge commits during the last 36 day(s) which contain a total of 356 files changed, 21786 insertions(+), 11275 deletions(-). The main changes are: 1) Rework BPF verifier log behavior and implement it as a rotating log by default with the option to retain old-style fixed log behavior, from Andrii Nakryiko. 2) Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params, from Christian Ehrig. 3) Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton, from Alexei Starovoitov. 4) Optimize hashmap lookups when key size is multiple of 4, from Anton Protopopov. 5) Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps, from David Vernet. 6) Add support for stashing local BPF kptr into a map value via bpf_kptr_xchg(). This is useful e.g. for rbtree node creation for new cgroups, from Dave Marchevsky. 7) Fix BTF handling of is_int_ptr to skip modifiers to work around tracing issues where a program cannot be attached, from Feng Zhou. 8) Migrate a big portion of test_verifier unit tests over to test_progs -a verifier_* via inline asm to ease {read,debug}ability, from Eduard Zingerman. 9) Several updates to the instruction-set.rst documentation which is subject to future IETF standardization (https://lwn.net/Articles/926882/), from Dave Thaler. 10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register known bits information propagation, from Daniel Borkmann. 11) Add skb bitfield compaction work related to BPF with the overall goal to make more of the sk_buff bits optional, from Jakub Kicinski. 12) BPF selftest cleanups for build id extraction which stand on its own from the upcoming integration work of build id into struct file object, from Jiri Olsa. 13) Add fixes and optimizations for xsk descriptor validation and several selftest improvements for xsk sockets, from Kal Conley. 14) Add BPF links for struct_ops and enable switching implementations of BPF TCP cong-ctls under a given name by replacing backing struct_ops map, from Kui-Feng Lee. 15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable offset stack read as earlier Spectre checks cover this, from Luis Gerhorst. 16) Fix issues in copy_from_user_nofault() for BPF and other tracers to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner and Alexei Starovoitov. 17) Add --json-summary option to test_progs in order for CI tooling to ease parsing of test results, from Manu Bretelle. 18) Batch of improvements and refactoring to prep for upcoming bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator, from Martin KaFai Lau. 19) Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations, from Quentin Monnet. 20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting the module name from BTF of the target and searching kallsyms of the correct module, from Viktor Malik. 21) Improve BPF verifier handling of '<const> <cond> <non_const>' to better detect whether in particular jmp32 branches are taken, from Yonghong Song. 22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock. A built-in cc or one from a kernel module is already able to write to app_limited, from Yixin Shen. Conflicts: Documentation/bpf/bpf_devel_QA.rst b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info") 0f10f647f455 ("bpf, docs: Use internal linking for link to netdev subsystem doc") https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/ include/net/ip_tunnels.h bc9d003dc48c3 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts") ac931d4cdec3d ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices") https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/ net/bpf/test_run.c e5995bc7e2ba ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption") 294635a8165a ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES") https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/ ==================== Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-04bpf: Teach verifier that certain helpers accept NULL pointer.Gravatar Alexei Starovoitov 1-1/+1
bpf_[sk|inode|task|cgrp]_storage_[get|delete]() and bpf_get_socket_cookie() helpers perform run-time check that sk|inode|task|cgrp pointer != NULL. Teach verifier about this fact and allow bpf programs to pass PTR_TO_BTF_ID | PTR_MAYBE_NULL into such helpers. It will be used in the subsequent patch that will do bpf_sk_storage_get(.., skb->sk, ...); Even when 'skb' pointer is trusted the 'sk' pointer may be NULL. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/bpf/20230404045029.82870-5-alexei.starovoitov@gmail.com