From: Amir Goldstein amir73il@gmail.com
commit 23a8ce16419a3066829ad4a8b7032a75817af65b upstream.
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: Amir Goldstein amir73il@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/overlayfs/file.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
--- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -531,9 +531,16 @@ static long ovl_fallocate(struct file *f const struct cred *old_cred; int ret;
+ inode_lock(inode); + /* Update mode */ + ovl_copyattr(ovl_inode_real(inode), 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); @@ -544,6 +551,9 @@ static long ovl_fallocate(struct file *f
fdput(real);
+out_unlock: + inode_unlock(inode); + return ret; }