On 05/26/2013 01:02 PM, Thierry Reding wrote:
- PGP Signed by an unknown key
On Fri, May 17, 2013 at 02:49:43PM +0300, Arto Merilainen wrote:
From: Terje Bergstrom tbergstrom@nvidia.com
This patch adds several fixes to host1x firewall:
- Host1x firewall does not survive if it expects a reloc, but user space didn't pass any relocs. Also it reset the reloc table for each gather, whereas they should be reset only per submit. Also class does not need to be reset for each class - once per submit is enough.
- For INCR opcode the check was not working properly at all.
- The firewall verified gather buffers before copying them. This allowed a malicious application to rewrite the buffer content by timing the rewrite carefully. This patch makes the buffer validation occur after copying the buffers.
Can these be split into separate patches, please? It's not only always good to split logical changes into separate patches but it also makes reviewing a lot more pleasant. It's hard to tell from this combined patch which changes belong together.
Sure.
I have a few additional comments inline.
diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c index f665d67..4f3c004 100644 --- a/drivers/gpu/host1x/job.c +++ b/drivers/gpu/host1x/job.c @@ -228,17 +228,15 @@ static unsigned int do_relocs(struct host1x_job *job, struct host1x_bo *cmdbuf) void *cmdbuf_page_addr = NULL;
/* pin & patch the relocs for one gather */
- while (i < job->num_relocs) {
- for (i = 0; i < job->num_relocs; ++i) {
Nit: I prefer post-increment where possible. For consistency.
Will do.
@@ -268,15 +263,15 @@ static unsigned int do_relocs(struct host1x_job *job, struct host1x_bo *cmdbuf) return 0; }
-static int check_reloc(struct host1x_reloc *reloc, struct host1x_bo *cmdbuf,
unsigned int offset)+static bool check_reloc(struct host1x_reloc *reloc, struct host1x_bo *cmdbuf,
unsigned int offset)
- if (reloc->cmdbuf != cmdbuf || reloc->cmdbuf_offset != offset)
return -EINVAL;
- if (!reloc || reloc->cmdbuf != cmdbuf || reloc->cmdbuf_offset != offset)
Is the additional !reloc check really necessary? Looking at the callers, they always pass in fw->relocarray, which in turn is only NULL if no buffers are to be relocated.
Yes, the additional check is necessary exactly for that reason. The code will fail if the userspace does not deliver a relocation array and still pushes data to an address register.
However, the code *should* check that there are relocations left before even coming here so I probably just fix this differently.
return true;
- return 0;
- return false; }
I wonder whether we should be changing the logic here and have the check_reloc() function return true if the relocation is good. I find that to be more intuitive.
I was also thinking that earlier. Will do.
@@ -508,6 +502,7 @@ int host1x_job_pin(struct host1x_job *job, struct device *dev) int err; unsigned int i, j; struct host1x *host = dev_get_drvdata(dev->parent);
- DECLARE_BITMAP(waitchk_mask, host1x_syncpt_nb_pts(host));
This is an unnecessary whitespace change.
Ops. Will fix.
- Arto