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| author | Andrew Morton <akpm@osdl.org> | 2006-12-07 07:36:40 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-07 19:39:34 +0300 |
| commit | 20aa7b21b1cbd1aa3fbf5fc14da5f7484a61a824 (patch) | |
| tree | ae0e9ec484c26f29f8f5cfa863a84943c27dfe9d | |
| parent | c140e110019f25ffa1c6f3f365b0c9103d0b8475 (diff) | |
| download | linux-20aa7b21b1cbd1aa3fbf5fc14da5f7484a61a824.tar.xz | |
[PATCH] probe_kernel_address() needs to do set_fs()
probe_kernel_address() purports to be generic, only it forgot to select
KERNEL_DS, so it presently won't work right on all architectures.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | include/linux/uaccess.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 67918c22339c..76c3fe325101 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -65,14 +65,22 @@ static inline unsigned long __copy_from_user_nocache(void *to, * do_page_fault() doesn't attempt to take mmap_sem. This makes * probe_kernel_address() suitable for use within regions where the caller * already holds mmap_sem, or other locks which nest inside mmap_sem. + * This must be a macro because __get_user() needs to know the types of the + * args. + * + * We don't include enough header files to be able to do the set_fs(). We + * require that the probe_kernel_address() caller will do that. */ #define probe_kernel_address(addr, retval) \ ({ \ long ret; \ + mm_segment_t old_fs = get_fs(); \ \ + set_fs(KERNEL_DS); \ pagefault_disable(); \ ret = __get_user(retval, addr); \ pagefault_enable(); \ + set_fs(old_fs); \ ret; \ }) |