From: Dan Carpenter Date: Fri, 23 Aug 2013 10:18:25 +0000 (+0300) Subject: gpu: host1x: fix an integer overflow check X-Git-Tag: v3.12-rc2~3^2~18^2~4 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f5fda676e9a3991aab159418f870351bc7d45d96;p=platform%2Fkernel%2Flinux-exynos.git gpu: host1x: fix an integer overflow check Tegra is a 32 bit arch. On 32 bit systems then size_t is 32 bits so "total" will never be higher than UINT_MAX because of integer overflows. We need cast to u64 first before doing the math. Also the addition earlier: unsigned int num_unpins = num_cmdbufs + num_relocs; That can overflow as well, but I think it's still safe because we check both "num_cmdbufs" and "num_relocs" again in this test. Signed-off-by: Dan Carpenter Signed-off-by: Thierry Reding --- diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c index cc80766..18a47f9 100644 --- a/drivers/gpu/host1x/job.c +++ b/drivers/gpu/host1x/job.c @@ -42,12 +42,12 @@ struct host1x_job *host1x_job_alloc(struct host1x_channel *ch, /* Check that we're not going to overflow */ total = sizeof(struct host1x_job) + - num_relocs * sizeof(struct host1x_reloc) + - num_unpins * sizeof(struct host1x_job_unpin_data) + - num_waitchks * sizeof(struct host1x_waitchk) + - num_cmdbufs * sizeof(struct host1x_job_gather) + - num_unpins * sizeof(dma_addr_t) + - num_unpins * sizeof(u32 *); + (u64)num_relocs * sizeof(struct host1x_reloc) + + (u64)num_unpins * sizeof(struct host1x_job_unpin_data) + + (u64)num_waitchks * sizeof(struct host1x_waitchk) + + (u64)num_cmdbufs * sizeof(struct host1x_job_gather) + + (u64)num_unpins * sizeof(dma_addr_t) + + (u64)num_unpins * sizeof(u32 *); if (total > ULONG_MAX) return NULL;