[Nouveau] [PATCH 13/14] drm/nouveau/perf: Prevent buffer oveflow

[Emil Velikov]

If the vbios is corrupted it can indicate more performance entries than the
ones statically allocated, causing overwriting of kernel memory

Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
---
 drivers/gpu/drm/nouveau/nouveau_perf.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_perf.c b/drivers/gpu/drm/nouveau/nouveau_perf.c
index af03fb4..36a9ae3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_perf.c
+++ b/drivers/gpu/drm/nouveau/nouveau_perf.c
@@ -61,7 +61,7 @@ nouveau_perf_entry(struct nouveau_device *ndev, int idx,
 		   u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
 {
 	u8 *perf = nouveau_perf_table(ndev, ver);
-	if (perf) {
+	if (perf && idx < NOUVEAU_PM_MAX_LEVEL) {
 		if (*ver >= 0x12 && *ver < 0x20 && idx < perf[2]) {
 			*hdr = perf[3];
 			*cnt = 0;
-- 
1.7.10.2