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 5.4-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-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3de466fbfbf43960c0751d8cf205dcdcc4bed7d6 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 aea5531559c06..4ebee6e4dc1f9 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;