diff options
| author | Jens Axboe <jens.axboe@oracle.com> | 2008-02-08 08:49:14 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-08 09:25:01 -0800 |
| commit | 8811930dc74a503415b35c4a79d14fb0b408a361 (patch) | |
| tree | 464a99a2be2f87b8e019fea231592ddf3ec38de7 /fs/splice.c | |
| parent | 66191dc622f5ff0a541524c4e96fdacfacfda206 (diff) | |
| download | lwn-8811930dc74a503415b35c4a79d14fb0b408a361.tar.gz lwn-8811930dc74a503415b35c4a79d14fb0b408a361.zip | |
splice: missing user pointer access verification
vmsplice_to_user() must always check the user pointer and length
with access_ok() before copying. Likewise, for the slow path of
copy_from_user_mmap_sem() we need to check that we may read from
the user region.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Wojciech Purczynski <cliph@research.coseinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/splice.c')
| -rw-r--r-- | fs/splice.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/splice.c b/fs/splice.c index 4ee49e86edde..14e2262c0a04 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -1179,6 +1179,9 @@ static int copy_from_user_mmap_sem(void *dst, const void __user *src, size_t n) { int partial; + if (!access_ok(VERIFY_READ, src, n)) + return -EFAULT; + pagefault_disable(); partial = __copy_from_user_inatomic(dst, src, n); pagefault_enable(); @@ -1387,6 +1390,11 @@ static long vmsplice_to_user(struct file *file, const struct iovec __user *iov, break; } + if (unlikely(!access_ok(VERIFY_WRITE, base, len))) { + error = -EFAULT; + break; + } + sd.len = 0; sd.total_len = len; sd.flags = flags; |