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| author | Al Viro <viro@ZenIV.linux.org.uk> | 2011-03-13 23:24:46 +0000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-13 16:29:07 -0700 |
| commit | c44ed965be7a84afaa07543c04eb97a5dfe93422 (patch) | |
| tree | df96d439962f923eee668e46dbff574b3603ca3f | |
| parent | c9a816c0ecb8cef8e6573a8eab47fc48c765e0a1 (diff) | |
| download | linux-c44ed965be7a84afaa07543c04eb97a5dfe93422.tar.bz2 | |
compat breakage in preadv() and pwritev()
Fix for a dumb preadv()/pwritev() compat bug - unlike the native
variants, the compat_... ones forget to check FMODE_P{READ,WRITE}, so
e.g. on pipe the native preadv() will fail with -ESPIPE and compat one
will act as readv() and succeed.
Not critical, but it's a clear bug with trivial fix, so IMO it's OK for
-final.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/compat.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/compat.c b/fs/compat.c index f6fd0a00e6cc..691c3fd8ce1d 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -1228,7 +1228,9 @@ compat_sys_preadv(unsigned long fd, const struct compat_iovec __user *vec, file = fget_light(fd, &fput_needed); if (!file) return -EBADF; - ret = compat_readv(file, vec, vlen, &pos); + ret = -ESPIPE; + if (file->f_mode & FMODE_PREAD) + ret = compat_readv(file, vec, vlen, &pos); fput_light(file, fput_needed); return ret; } @@ -1285,7 +1287,9 @@ compat_sys_pwritev(unsigned long fd, const struct compat_iovec __user *vec, file = fget_light(fd, &fput_needed); if (!file) return -EBADF; - ret = compat_writev(file, vec, vlen, &pos); + ret = -ESPIPE; + if (file->f_mode & FMODE_PWRITE) + ret = compat_writev(file, vec, vlen, &pos); fput_light(file, fput_needed); return ret; } |