The patch below does not apply to the 5.15-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.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 277627b431a0a6401635c416a21b2a0f77a77347 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025071424-payroll-posh-4e3e@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From 277627b431a0a6401635c416a21b2a0f77a77347 Mon Sep 17 00:00:00 2001 From: Al Viro viro@zeniv.linux.org.uk Date: Sun, 6 Jul 2025 02:26:45 +0100 Subject: [PATCH] ksmbd: fix a mount write count leak in ksmbd_vfs_kern_path_locked()

If the call of ksmbd_vfs_lock_parent() fails, we drop the parent_path references and return an error. We need to drop the write access we just got on parent_path->mnt before we drop the mount reference - callers assume that ksmbd_vfs_kern_path_locked() returns with mount write access grabbed if and only if it has returned 0.

Fixes: 864fb5d37163 ("ksmbd: fix possible deadlock in smb2_open") Signed-off-by: Al Viro viro@zeniv.linux.org.uk Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com

diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c index 0f3aad12e495..d3437f6644e3 100644 --- a/fs/smb/server/vfs.c +++ b/fs/smb/server/vfs.c @@ -1282,6 +1282,7 @@ int ksmbd_vfs_kern_path_locked(struct ksmbd_work *work, char *name,

err = ksmbd_vfs_lock_parent(parent_path->dentry, path->dentry); if (err) { + mnt_drop_write(parent_path->mnt); path_put(path); path_put(parent_path); }