The commit
19b07cb4a187 ("i2c: i801: Register optional lis3lv02d I2C device on Dell machines")
introduced a new check in order to enumerate some slave devices on Dell
machines. Though, it brings a regression on machines where DMI vendor is not set.
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 8 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc4-next-20190613+ #317
RIP: 0010:strcmp+0xc/0x20
To fix this crash, check if vendor field is present before accessing to it.
Fixes: 19b07cb4a187 ("i2c: i801: Register optional lis3lv02d I2C device on Dell machines")
Cc: Pali Rohár <pali.rohar@xxxxxxxxx>
Cc: Jean Delvare <jdelvare@xxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-i801.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 2d9f77ea02e4..694eb636b40b 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -1180,7 +1180,7 @@ static bool is_dell_system_with_lis3lv02d(void)
const char *vendor;
vendor = dmi_get_system_info(DMI_SYS_VENDOR);
- if (strcmp(vendor, "Dell Inc.") != 0)
+ if (!vendor || strcmp(vendor, "Dell Inc."))
return false;
/*
--
2.20.1
