I met below error during boot with i915 builtin if pass
"i915.mitigations=off":
[ 0.015589] Booting kernel: `off' invalid for parameter `i915.mitigations'
The reason is slab subsystem isn't ready at that time, so kstrdup()
returns NULL. Fix this issue by using stack var instead of kstrdup().
Fixes: 984cadea032b ("drm/i915: Allow the sysadmin to override security mitigations")
Signed-off-by: Jisheng Zhang <[email protected]>
---
Since v2:
- Use strscpy() per Ville's suggestion.
Since v1:
- Ensure "str" is properly terminated. Thanks Ville for pointing this out.
drivers/gpu/drm/i915/i915_mitigations.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_mitigations.c b/drivers/gpu/drm/i915/i915_mitigations.c
index 84f12598d145..70944764a77e 100644
--- a/drivers/gpu/drm/i915/i915_mitigations.c
+++ b/drivers/gpu/drm/i915/i915_mitigations.c
@@ -29,15 +29,13 @@ bool i915_mitigate_clear_residuals(void)
static int mitigations_set(const char *val, const struct kernel_param *kp)
{
unsigned long new = ~0UL;
- char *str, *sep, *tok;
+ char str[64], *sep, *tok;
bool first = true;
int err = 0;
BUILD_BUG_ON(ARRAY_SIZE(names) >= BITS_PER_TYPE(mitigations));
- str = kstrdup(val, GFP_KERNEL);
- if (!str)
- return -ENOMEM;
+ strscpy(str, val, sizeof(str));
for (sep = str; (tok = strsep(&sep, ","));) {
bool enable = true;
@@ -86,7 +84,6 @@ static int mitigations_set(const char *val, const struct kernel_param *kp)
break;
}
}
- kfree(str);
if (err)
return err;
--
2.31.0