[PATCH 5.12 168/296] net: fujitsu: fix potential null-ptr-deref

Greg Kroah-Hartman
2021-05-31T16:30:12Z

From: Anirudh Rayabharam <mail@anirudhrb.com>

[ Upstream commit 52202be1cd996cde6e8969a128dc27ee45a7cb5e ]

In fmvj18x_get_hwinfo(), if ioremap fails there will be NULL pointer
deref. To fix this, check the return value of ioremap and return -1
to the caller in case of failure.

Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
Link: https://lore.kernel.org/r/20210503115736.2104747-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/fujitsu/fmvj18x_cs.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/fujitsu/fmvj18x_cs.c b/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
index dc90c61fc827..b0c0504950d8 100644
--- a/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
+++ b/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
@@ -547,6 +547,11 @@ static int fmvj18x_get_hwinfo(struct pcmcia_device *link, u_char *node_id)
return -1;

base = ioremap(link->resource[2]->start, resource_size(link->resource[2]));
+ if (!base) {
+ pcmcia_release_window(link, link->resource[2]);
+ return -1;
+ }
+
pcmcia_map_mem_page(link, link->resource[2], 0);

/*
--
2.30.2