The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 996fc4477a0ea28226b30d175f053fb6f9a4fa36 Mon Sep 17 00:00:00 2001

From: Theodore Ts'o tytso@mit.edu Date: Sun, 10 Dec 2017 23:44:11 -0500 Subject: [PATCH] ext4: add missing error check in __ext4_new_inode()

It's possible for ext4_get_acl() to return an ERR_PTR. So we need to add a check for this case in __ext4_new_inode(). Otherwise on an error we can end up oops the kernel.

This was getting triggered by xfstests generic/388, which is a test which exercises the shutdown code path.

Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@vger.kernel.org

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index b4267d72f249..b32cf263750d 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -816,6 +816,8 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir, #ifdef CONFIG_EXT4_FS_POSIX_ACL struct posix_acl *p = get_acl(dir, ACL_TYPE_DEFAULT);

+ if (IS_ERR(p)) + return ERR_CAST(p); if (p) { int acl_size = p->a_count * sizeof(ext4_acl_entry);