summary refs log tree commit diff
diff options
context:
space:
mode:
authorJeff Mahoney <jeffm@suse.com>2009-05-11 14:25:34 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-05-11 12:18:06 -0700
commit2b79bc4f7ebbd5af3c8b867968f9f15602d5f802 (patch)
tree135f195357e108b1cc7b5ef0a09d1e32b79fcce0
parentfd18de50b9e7965f93d231e7390436fb8900c0e6 (diff)
downloadlinux-2b79bc4f7ebbd5af3c8b867968f9f15602d5f802.tar.gz
dup2: Fix return value with oldfd == newfd and invalid fd
The return value of dup2 when oldfd == newfd and the fd isn't valid is
not getting properly sign extended.  We end up with 4294967287 instead
of -EBADF.

I've reproduced this on SLE11 (2.6.27.21), openSUSE Factory
(2.6.29-rc5), and Ubuntu 9.04 (2.6.28).

This patch uses a signed int for the error value so it is properly
extended.

Commit 6c5d0512a091480c9f981162227fdb1c9d70e555 introduced this
regression.

Reported-by: Jiri Dluhos <jdluhos@novell.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--fs/fcntl.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/fcntl.c b/fs/fcntl.c
index cc8e4de2fee5..1ad703150dee 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -117,11 +117,13 @@ SYSCALL_DEFINE2(dup2, unsigned int, oldfd, unsigned int, newfd)
 {
 	if (unlikely(newfd == oldfd)) { /* corner case */
 		struct files_struct *files = current->files;
+		int retval = oldfd;
+
 		rcu_read_lock();
 		if (!fcheck_files(files, oldfd))
-			oldfd = -EBADF;
+			retval = -EBADF;
 		rcu_read_unlock();
-		return oldfd;
+		return retval;
 	}
 	return sys_dup3(oldfd, newfd, 0);
 }