@@ -1493,14 +1493,22 @@ static int ovl_get_layers(struct super_block *sb, struct ovl_fs *ofs,
if (err < 0)
goto out;
+ /*
+ * Check if lower root conflicts with this overlay layers before checking
+ * if it is in-use as upperdir/workdir of "another" mount, because we do
+ * not bother to check in ovl_is_inuse() if the upperdir/workdir is in fact
+ * in-use by our upperdir/workdir.
+ */
err = ovl_setup_trap(sb, stack[i].dentry, &trap, "lowerdir");
if (err)
goto out;
if (ovl_is_inuse(stack[i].dentry)) {
err = ovl_report_in_use(ofs, "lowerdir");
- if (err)
+ if (err) {
+ iput(trap);
goto out;
+ }
}
mnt = clone_private_mount(&stack[i]);
When "ovl_is_inuse" true case, trap inode reference not put. plus adding the comment explaining sequence of ovl_is_inuse after ovl_setup_trap. Fixes: 0be0bfd2de9d ("ovl: fix regression caused by overlapping layers..") Cc: <stable@vger.kernel.org> # v4.19+ Reviewed-by: Amir Goldstein <amir73il@gmail.com> > Signed-off-by: youngjun <her0gyugyu@gmail.com> > --- > fs/overlayfs/super.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c > index 91476bc422f9..0396793dadb8 100644 > --- a/fs/overlayfs/super.c > +++ b/fs/overlayfs/super.c > @@ -1029,6 +1029,12 @@ static const struct xattr_handler *ovl_xattr_handlers[] = { > NULL > }; > > +/* > + * Check if lower root conflicts with this overlay layers before checking > + * if it is in-use as upperdir/workdir of "another" mount, because we do > + * not bother to check in ovl_is_inuse() if the upperdir/workdir is in fact > + * in-use by our upperdir/workdir. > + */ Signed-off-by: youngjun <her0gyugyu@gmail.com> --- fs/overlayfs/super.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)