From: Daniel Rosenberg <drosen@google.com>
Date: Wed, 7 Jun 2017 19:44:50 +0000 (-0700)
Subject: ANDROID: sdcardfs: d_splice_alias can return error values
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d5dadb6c35fc11537280190084ed94b20be26571;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

ANDROID: sdcardfs: d_splice_alias can return error values

We must check that d_splice_alias was successful before using its
output.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Bug: 62390017
Change-Id: Ifda0a052fb3f67e35c635a4e5e907876c5400978
---

diff --git a/fs/sdcardfs/lookup.c b/fs/sdcardfs/lookup.c
index 83f6083e5aad..7dab5f76896b 100644
--- a/fs/sdcardfs/lookup.c
+++ b/fs/sdcardfs/lookup.c
@@ -199,7 +199,8 @@ static struct dentry *__sdcardfs_interpose(struct dentry *dentry,
 
 	ret_dentry = d_splice_alias(inode, dentry);
 	dentry = ret_dentry ?: dentry;
-	update_derived_permission_lock(dentry);
+	if (!IS_ERR(dentry))
+		update_derived_permission_lock(dentry);
 out:
 	return ret_dentry;
 }