net: fujitsu: fix potential null-ptr-deref

[ 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>

diff --git a/drivers/net/ethernet/fujitsu/fmvj18x_cs.c b/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
index 399cfd217288d9e32b0fd9ba188e974a4663a87e..cfda55bfa811a95a52e7250e73c8d47965aee63a 100644 (file)
--- a/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
+++ b/drivers/net/ethernet/fujitsu/fmvj18x_cs.c
@@ -548,6 +548,11 @@ 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);
 
     /*