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author | 2023-01-01 11:19:50 -0800 | |
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committer | 2023-01-01 11:19:50 -0800 | |
commit | 5b129817aedb03d94fb960e7a34d0f5eaa20a2f2 (patch) | |
tree | 618e7fe0a1c25fb381e86506735076fca0e2d09b | |
parent | Merge tag 'locking_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux... (diff) | |
parent | x86/kprobes: Fix optprobe optimization check with CONFIG_RETHUNK (diff) | |
download | linux-5b129817aedb03d94fb960e7a34d0f5eaa20a2f2.tar.gz linux-5b129817aedb03d94fb960e7a34d0f5eaa20a2f2.tar.bz2 linux-5b129817aedb03d94fb960e7a34d0f5eaa20a2f2.zip |
Merge tag 'x86_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Two fixes to correct how kprobes handles INT3 now that they're added
by other functionality like the rethunks and not only kgdb
- Remove __init section markings of two functions which are referenced
by a function in the .text section
* tag 'x86_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kprobes: Fix optprobe optimization check with CONFIG_RETHUNK
x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK
x86/calldepth: Fix incorrect init section references
-rw-r--r-- | arch/x86/kernel/callthunks.c | 4 | ||||
-rw-r--r-- | arch/x86/kernel/kprobes/core.c | 10 | ||||
-rw-r--r-- | arch/x86/kernel/kprobes/opt.c | 28 |
3 files changed, 17 insertions, 25 deletions
diff --git a/arch/x86/kernel/callthunks.c b/arch/x86/kernel/callthunks.c index 7d2c75ec9a8c..ffea98f9064b 100644 --- a/arch/x86/kernel/callthunks.c +++ b/arch/x86/kernel/callthunks.c @@ -119,7 +119,7 @@ static bool is_coretext(const struct core_text *ct, void *addr) return within_module_coretext(addr); } -static __init_or_module bool skip_addr(void *dest) +static bool skip_addr(void *dest) { if (dest == error_entry) return true; @@ -181,7 +181,7 @@ static const u8 nops[] = { 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, }; -static __init_or_module void *patch_dest(void *dest, bool direct) +static void *patch_dest(void *dest, bool direct) { unsigned int tsize = SKL_TMPL_SIZE; u8 *pad = dest - tsize; diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 66299682b6b7..b36f3c367cb2 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -37,6 +37,7 @@ #include <linux/extable.h> #include <linux/kdebug.h> #include <linux/kallsyms.h> +#include <linux/kgdb.h> #include <linux/ftrace.h> #include <linux/kasan.h> #include <linux/moduleloader.h> @@ -281,12 +282,15 @@ static int can_probe(unsigned long paddr) if (ret < 0) return 0; +#ifdef CONFIG_KGDB /* - * Another debugging subsystem might insert this breakpoint. - * In that case, we can't recover it. + * If there is a dynamically installed kgdb sw breakpoint, + * this function should not be probed. */ - if (insn.opcode.bytes[0] == INT3_INSN_OPCODE) + if (insn.opcode.bytes[0] == INT3_INSN_OPCODE && + kgdb_has_hit_break(addr)) return 0; +#endif addr += insn.length; } diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index e6b8c5362b94..e57e07b0edb6 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -15,6 +15,7 @@ #include <linux/extable.h> #include <linux/kdebug.h> #include <linux/kallsyms.h> +#include <linux/kgdb.h> #include <linux/ftrace.h> #include <linux/objtool.h> #include <linux/pgtable.h> @@ -279,19 +280,6 @@ static int insn_is_indirect_jump(struct insn *insn) return ret; } -static bool is_padding_int3(unsigned long addr, unsigned long eaddr) -{ - unsigned char ops; - - for (; addr < eaddr; addr++) { - if (get_kernel_nofault(ops, (void *)addr) < 0 || - ops != INT3_INSN_OPCODE) - return false; - } - - return true; -} - /* Decode whole function to ensure any instructions don't jump into target */ static int can_optimize(unsigned long paddr) { @@ -334,15 +322,15 @@ static int can_optimize(unsigned long paddr) ret = insn_decode_kernel(&insn, (void *)recovered_insn); if (ret < 0) return 0; - +#ifdef CONFIG_KGDB /* - * In the case of detecting unknown breakpoint, this could be - * a padding INT3 between functions. Let's check that all the - * rest of the bytes are also INT3. + * If there is a dynamically installed kgdb sw breakpoint, + * this function should not be probed. */ - if (insn.opcode.bytes[0] == INT3_INSN_OPCODE) - return is_padding_int3(addr, paddr - offset + size) ? 1 : 0; - + if (insn.opcode.bytes[0] == INT3_INSN_OPCODE && + kgdb_has_hit_break(addr)) + return 0; +#endif /* Recover address */ insn.kaddr = (void *)addr; insn.next_byte = (void *)(addr + insn.length); |