From: Dan Carpenter Date: Fri, 30 Jun 2017 10:59:15 +0300 Subject: drm/msm: fix an integer overflow test Git-commit: 65e93108891e571f177c202add9288eda9ac4100 Patch-mainline: v4.13-rc5 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 We recently added an integer overflow check but it needs an additional tweak to work properly on 32 bit systems. The problem is that we're doing the right hand side of the assignment as type unsigned long so the max it will have an integer overflow instead of being larger than SIZE_MAX. That means the "sz > SIZE_MAX" condition is never true even on 32 bit systems. We need to first cast it to u64 and then do the math. Fixes: 4a630fadbb29 ("drm/msm: Fix potential buffer overflow issue") Signed-off-by: Dan Carpenter Acked-by: Jordan Crouse Signed-off-by: Rob Clark Acked-by: Petr Tesarik --- drivers/gpu/drm/msm/msm_gem_submit.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/msm/msm_gem_submit.c +++ b/drivers/gpu/drm/msm/msm_gem_submit.c @@ -34,8 +34,8 @@ static struct msm_gem_submit *submit_cre struct msm_gpu *gpu, uint32_t nr_bos, uint32_t nr_cmds) { struct msm_gem_submit *submit; - uint64_t sz = sizeof(*submit) + (nr_bos * sizeof(submit->bos[0])) + - (nr_cmds * sizeof(submit->cmd[0])); + uint64_t sz = sizeof(*submit) + ((u64)nr_bos * sizeof(submit->bos[0])) + + ((u64)nr_cmds * sizeof(submit->cmd[0])); if (sz > SIZE_MAX) return NULL;