From 0dc54bd4d6e03be1f0b678c4297170b79f1a44ab Mon Sep 17 00:00:00 2001
From: Dominique Martinet <asmadeus@codewreck.org>
Date: Wed, 3 Nov 2021 17:34:05 +0900
Subject: [PATCH] fscache_cookie_enabled: check cookie is valid before
accessing it
fscache_cookie_enabled() could be called on NULL cookies and cause a
null pointer dereference when accessing cookie flags: just make sure
the cookie is valid first
Suggested-by: David Howells <dhowells@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
---
include/linux/fscache.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/fscache.h b/include/linux/fscache.h
index a4dab59986137..3b2282c157f79 100644
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -167,7 +167,7 @@ struct fscache_cookie {
static inline bool fscache_cookie_enabled(struct fscache_cookie *cookie)
{
- return test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+ return fscache_cookie_valid(cookie) && test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
}
/*
--
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