If ioremap fails, NULL pointer dereference will happen and
leading to a kernel panic when access the virtual address
in check_signature().
Fix it by check the return value of ioremap.
Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Cc: Miloslav Trmac <mitr@xxxxxxxx>
Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx>
Cc: linux-input@xxxxxxxxxxxxxxx
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
drivers/input/misc/wistron_btns.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/input/misc/wistron_btns.c b/drivers/input/misc/wistron_btns.c
index 43e67f546366..a82ec3d102b4 100644
--- a/drivers/input/misc/wistron_btns.c
+++ b/drivers/input/misc/wistron_btns.c
@@ -107,7 +107,10 @@ static int __init map_bios(void)
ssize_t offset;
u32 entry_point;
- base = ioremap(0xF0000, 0x10000); /* Can't fail */
+ base = ioremap(0xF0000, 0x10000);
+ if (!base)
+ return -ENOMEM;
+
offset = locate_wistron_bios(base);
if (offset < 0) {
printk(KERN_ERR "wistron_btns: BIOS entry point not found\n");
--
2.20.1
