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 dan.carpenter@oracle.com --- This is something I spotted in code review. I can't actually compile this code. I assume this overflow test has security implications.
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;