From 2bc7e7c1a3bc9bd0cbf0f71006f6fe7ef24a00c2 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 23 May 2023 23:49:50 -0400 Subject: [PATCH] ext4: disallow ea_inodes with extended attributes An ea_inode stores the value of an extended attribute; it can not have extended attributes itself, or this will cause recursive nightmares. Add a check in ext4_iget() to make sure this is the case. Cc: stable@kernel.org Reported-by: syzbot+e44749b6ba4d0434cd47@syzkaller.appspotmail.com Signed-off-by: Theodore Ts'o Link: https://lore.kernel.org/r/20230524034951.779531-4-tytso@mit.edu Signed-off-by: Theodore Ts'o --- fs/ext4/inode.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 258f3cbed347..02de439bf1f0 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4647,6 +4647,9 @@ static const char *check_igot_inode(struct inode *inode, ext4_iget_flags flags) if (flags & EXT4_IGET_EA_INODE) { if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) return "missing EA_INODE flag"; + if (ext4_test_inode_state(inode, EXT4_STATE_XATTR) || + EXT4_I(inode)->i_file_acl) + return "ea_inode with extended attributes"; } else { if ((EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) return "unexpected EA_INODE flag";