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From:   Colin Foster <colin.foster@in-advantage.com>
To:     linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Cc:     =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Ilias Apalodimas <ilias.apalodimas@linaro.org>,
        Jesper Dangaard Brouer <hawk@kernel.org>
Subject: [net RFC v1 1/1] page_pool: fix NULL dereference crash
Date:   Fri, 21 Jan 2022 16:56:44 -0800
Message-Id: <20220122005644.802352-2-colin.foster@in-advantage.com>
In-Reply-To: <20220122005644.802352-1-colin.foster@in-advantage.com>
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Check for the existence of page pool params before dereferencing. This can
cause crashes in certain conditions.

Fixes: 35b2e549894b ("page_pool: Add callback to init pages when they are
allocated")

Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
---
 net/core/page_pool.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index bd62c01a2ec3..641f849c95e7 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -213,7 +213,7 @@ static void page_pool_set_pp_info(struct page_pool *pool,
 {
 	page->pp = pool;
 	page->pp_magic |= PP_SIGNATURE;
-	if (pool->p.init_callback)
+	if (pool->p && pool->p.init_callback)
 		pool->p.init_callback(page, pool->p.init_arg);
 }
 
-- 
2.25.1