From 9c3407b99d99f6bfbdace345c070b35eb661f66f Mon Sep 17 00:00:00 2001 From: Bill XIE Date: Tue, 4 Apr 2023 10:59:13 +0800 Subject: [PATCH] nb/intel/gm45: Prevent null-deref in get_blc_pwm_freq_value() IF its first call is get_blc_pwm_freq_value(NULL), null dereference will occur. Now when the parameter is NULL, it will return the value of the static blc_pwm_freq directly, so the original behavior is kept. Signed-off-by: Bill XIE Change-Id: I32354aa0fe1a3ca725c2031f973ffad0bda81ad5 Reviewed-on: https://review.coreboot.org/c/coreboot/+/74179 Tested-by: build bot (Jenkins) Reviewed-by: Arthur Heymans --- src/northbridge/intel/gm45/gma.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/northbridge/intel/gm45/gma.c b/src/northbridge/intel/gm45/gma.c index 7df9106f2f..804382224d 100644 --- a/src/northbridge/intel/gm45/gma.c +++ b/src/northbridge/intel/gm45/gma.c @@ -67,7 +67,8 @@ u16 get_blc_pwm_freq_value(const char *edid_ascii_string) int i; int blc_array_len; - if (blc_pwm_freq > 0) + /* Prevent null-deref on strcmp() below */ + if (blc_pwm_freq > 0 || !edid_ascii_string) return blc_pwm_freq; blc_array_len = get_blc_values(&blc_pwm);