This is a note to let you know that I've just added the patch titled
jfs: Fix uninit-value access of new_ea in ea_buffer
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
jfs-fix-uninit-value-access-of-new_ea-in-ea_buffer.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 254f8008f81bb17c7effeae06e1ed0cf610ba04e
Author: Zhao Mengmeng <zhaomengmeng@xxxxxxxxxx>
Date: Wed Sep 4 09:07:58 2024 +0800
jfs: Fix uninit-value access of new_ea in ea_buffer
[ Upstream commit 2b59ffad47db1c46af25ccad157bb3b25147c35c ]
syzbot reports that lzo1x_1_do_compress is using uninit-value:
=====================================================
BUG: KMSAN: uninit-value in lzo1x_1_do_compress+0x19f9/0x2510 lib/lzo/lzo1x_compress.c:178
...
Uninit was stored to memory at:
ea_put fs/jfs/xattr.c:639 [inline]
...
Local variable ea_buf created at:
__jfs_setxattr+0x5d/0x1ae0 fs/jfs/xattr.c:662
__jfs_xattr_set+0xe6/0x1f0 fs/jfs/xattr.c:934
=====================================================
The reason is ea_buf->new_ea is not initialized properly.
Fix this by using memset to empty its content at the beginning
in ea_get().
Reported-by: syzbot+02341e0daa42a15ce130@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=02341e0daa42a15ce130
Signed-off-by: Zhao Mengmeng <zhaomengmeng@xxxxxxxxxx>
Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index 8ef8dfc3c1944..76b89718fd526 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -434,6 +434,8 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
int rc;
int quota_allocation = 0;
+ memset(&ea_buf->new_ea, 0, sizeof(ea_buf->new_ea));
+
/* When fsck.jfs clears a bad ea, it doesn't clear the size */
if (ji->ea.flag == 0)
ea_size = 0;
