diff options
| author |  Christophe Leroy <christophe.leroy@c-s.fr>
| 2020-04-03 07:20:51 +0000 |
|---|---|---|
| committer |  Michael Ellerman <mpe@ellerman.id.au>
| 2020-05-01 12:35:21 +1000 |
| commit | 41cd780524674082b037e7c8461f90c5e42103f0 (patch) | |
| tree | eb705efdf71be777efedd2cd76e1f47d7cd753e2 /lib | |
| parent | uaccess: Add user_read_access_begin/end and user_write_access_begin/end (diff) | |
| download | linux-41cd780524674082b037e7c8461f90c5e42103f0.tar.gz linux-41cd780524674082b037e7c8461f90c5e42103f0.tar.bz2 linux-41cd780524674082b037e7c8461f90c5e42103f0.zip | |
uaccess: Selectively open read or write user access
When opening user access to only perform reads, only open read access.
When opening user access to only perform writes, only open write
access.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2e73bc57125c2c6ab12a587586a4eed3a47105fc.1585898438.git.christophe.leroy@c-s.fr
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/strncpy_from_user.c | 4 | ||||
| -rw-r--r-- | lib/strnlen_user.c | 4 | ||||
| -rw-r--r-- | lib/usercopy.c | 6 |
3 files changed, 7 insertions, 7 deletions
diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c index 706020b06617..b90ec550183a 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -116,9 +116,9 @@ long strncpy_from_user(char *dst, const char __user *src, long count) kasan_check_write(dst, count); check_object_size(dst, count, false); - if (user_access_begin(src, max)) { + if (user_read_access_begin(src, max)) { retval = do_strncpy_from_user(dst, src, count, max); - user_access_end(); + user_read_access_end(); return retval; } } diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index 41670d4a5816..1616710b8a82 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -109,9 +109,9 @@ long strnlen_user(const char __user *str, long count) if (max > count) max = count; - if (user_access_begin(str, max)) { + if (user_read_access_begin(str, max)) { retval = do_strnlen_user(str, count, max); - user_access_end(); + user_read_access_end(); return retval; } } diff --git a/lib/usercopy.c b/lib/usercopy.c index cbb4d9ec00f2..ca2a697a2061 100644 --- a/lib/usercopy.c +++ b/lib/usercopy.c @@ -58,7 +58,7 @@ int check_zeroed_user(const void __user *from, size_t size) from -= align; size += align; - if (!user_access_begin(from, size)) + if (!user_read_access_begin(from, size)) return -EFAULT; unsafe_get_user(val, (unsigned long __user *) from, err_fault); @@ -79,10 +79,10 @@ int check_zeroed_user(const void __user *from, size_t size) val &= aligned_byte_mask(size); done: - user_access_end(); + user_read_access_end(); return (val == 0); err_fault: - user_access_end(); + user_read_access_end(); return -EFAULT; } EXPORT_SYMBOL(check_zeroed_user); |