From: Zhao Mengmeng zhaomengmeng@kylinos.cn

mainline inclusion from mainline-v6.12-rc1 commit 2b59ffad47db1c46af25ccad157bb3b25147c35c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYR97 CVE: CVE-2024-49900

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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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

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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@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=02341e0daa42a15ce130 Signed-off-by: Zhao Mengmeng zhaomengmeng@kylinos.cn Signed-off-by: Dave Kleikamp dave.kleikamp@oracle.com Signed-off-by: Hongbo Li lihongbo22@huawei.com --- fs/jfs/xattr.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c index 37b984692ca9..bb8c4583f065 100644 --- a/fs/jfs/xattr.c +++ b/fs/jfs/xattr.c @@ -447,6 +447,8 @@ 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;