From: Jiang Liu <gerry@linux.alibaba.com>
Date: Fri, 7 Feb 2025 06:44:14 +0000 (+0800)
Subject: drm/amdgpu: avoid buffer overflow attach in smu_sys_set_pp_table()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1abb2648698bf10783d2236a6b4a7ca5e8021699;p=users%2Fhch%2Fmisc.git

drm/amdgpu: avoid buffer overflow attach in smu_sys_set_pp_table()

It malicious user provides a small pptable through sysfs and then
a bigger pptable, it may cause buffer overflow attack in function
smu_sys_set_pp_table().

Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Jiang Liu <gerry@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
---

diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
index 8ca793c222ff..ed9dac00ebfb 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
@@ -612,7 +612,8 @@ static int smu_sys_set_pp_table(void *handle,
 		return -EIO;
 	}
 
-	if (!smu_table->hardcode_pptable) {
+	if (!smu_table->hardcode_pptable || smu_table->power_play_table_size < size) {
+		kfree(smu_table->hardcode_pptable);
 		smu_table->hardcode_pptable = kzalloc(size, GFP_KERNEL);
 		if (!smu_table->hardcode_pptable)
 			return -ENOMEM;