From 47b5d0a7532d39e42a938f81e3904268145c341d Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 30 Dec 2021 20:23:09 +0100 Subject: [PATCH] fs/mount_setattr: always cleanup mount_kattr commit 012e332286e2bb9f6ac77d195f17e74b2963d663 upstream. Make sure that finish_mount_kattr() is called after mount_kattr was succesfully built in both the success and failure case to prevent leaking any references we took when we built it. We returned early if path lookup failed thereby risking to leak an additional reference we took when building mount_kattr when an idmapped mount was requested. Cc: linux-fsdevel@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 9caccd41541a ("fs: introduce MOUNT_ATTR_IDMAP") Signed-off-by: Christian Brauner Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/namespace.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/namespace.c b/fs/namespace.c index 659a8f39c61a..b696543adab8 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -4263,12 +4263,11 @@ SYSCALL_DEFINE5(mount_setattr, int, dfd, const char __user *, path, return err; err = user_path_at(dfd, path, kattr.lookup_flags, &target); - if (err) - return err; - - err = do_mount_setattr(&target, &kattr); + if (!err) { + err = do_mount_setattr(&target, &kattr); + path_put(&target); + } finish_mount_kattr(&kattr); - path_put(&target); return err; }