From 7e48315397067f9ca294e222bfaab0ecced8bd7f Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Mon, 17 Oct 2022 17:06:39 +0200 Subject: [PATCH] ovl: remove privs in ovl_fallocate() [ Upstream commit 23a8ce16419a3066829ad4a8b7032a75817af65b ] Underlying fs doesn't remove privs because fallocate is called with privileged mounter credentials. This fixes some failure in fstests generic/683..687. Fixes: aab8848cee5e ("ovl: add ovl_fallocate()") Acked-by: Miklos Szeredi Signed-off-by: Amir Goldstein Signed-off-by: Christian Brauner (Microsoft) Signed-off-by: Sasha Levin --- fs/overlayfs/file.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 755a11c..d066be3 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -517,9 +517,16 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len const struct cred *old_cred; int ret; + inode_lock(inode); + /* Update mode */ + ovl_copyattr(inode); + ret = file_remove_privs(file); + if (ret) + goto out_unlock; + ret = ovl_real_fdget(file, &real); if (ret) - return ret; + goto out_unlock; old_cred = ovl_override_creds(file_inode(file)->i_sb); ret = vfs_fallocate(real.file, mode, offset, len); @@ -530,6 +537,9 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len fdput(real); +out_unlock: + inode_unlock(inode); + return ret; } -- 2.7.4