From: Amir Goldstein amir73il@gmail.com
[ 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 mszeredi@redhat.com Signed-off-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Christian Brauner (Microsoft) brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 362a4eed92b5..a34f8042724c 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; }