redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

gpu: host1x: Copy gathers before verification 

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.

Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
hifive-unleashed-5.1
Arto Merilainen 2013-05-29 13:26:05 +03:00 committed by Thierry Reding
parent afac0e43c6
commit 3364cd2890
1 changed files with 20 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
drivers/gpu/host1x/job.c
View File

@ -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++) {
struct host1x_reloc *reloc = &job->relocarray[i];
u32 reloc_addr = (job->reloc_addr_phys[i] +
reloc->target_offset) >> reloc->shift;
u32 *target;
/* skip all other gathers */
if (!(reloc->cmdbuf && cmdbuf == reloc->cmdbuf)) {
i++;
if (cmdbuf != reloc->cmdbuf)
continue;
}
if (last_page != reloc->cmdbuf_offset >> PAGE_SHIFT) {
if (cmdbuf_page_addr)
@ -257,9 +255,6 @@ static unsigned int do_relocs(struct host1x_job *job, struct host1x_bo *cmdbuf)
target = cmdbuf_page_addr + (reloc->cmdbuf_offset & ~PAGE_MASK);
*target = reloc_addr;
/* mark this gather as handled */
reloc->cmdbuf = 0;
}
if (cmdbuf_page_addr)
@ -378,15 +373,13 @@ static int check_nonincr(struct host1x_firewall *fw)
static int validate(struct host1x_firewall *fw, struct host1x_job_gather *g)
{
u32 *cmdbuf_base;
u32 *cmdbuf_base = (u32 *)fw->job->gather_copy_mapped +
(g->offset / sizeof(u32));
int err = 0;
if (!fw->job->is_addr_reg)
return 0;
cmdbuf_base = host1x_bo_mmap(g->bo);
if (!cmdbuf_base)
return -ENOMEM;
fw->words = g->words;
fw->cmdbuf_id = g->bo;
fw->offset = 0;
@ -453,10 +446,17 @@ out:
static inline int copy_gathers(struct host1x_job *job, struct device *dev)
{
struct host1x_firewall fw;
size_t size = 0;
size_t offset = 0;
int i;
fw.job = job;
fw.dev = dev;
fw.reloc = job->relocarray;
fw.num_relocs = job->num_relocs;
fw.class = 0;
for (i = 0; i < job->num_gathers; i++) {
struct host1x_job_gather *g = &job->gathers[i];
size += g->words * sizeof(u32);
@ -477,14 +477,19 @@ static inline int copy_gathers(struct host1x_job *job, struct device *dev)
struct host1x_job_gather *g = &job->gathers[i];
void *gather;
/* Copy the gather */
gather = host1x_bo_mmap(g->bo);
memcpy(job->gather_copy_mapped + offset, gather + g->offset,
g->words * sizeof(u32));
host1x_bo_munmap(g->bo, gather);
/* Store the location in the buffer */
g->base = job->gather_copy;
g->offset = offset;
g->bo = NULL;
/* Validate the job */
if (validate(&fw, g))
return -EINVAL;
offset += g->words * sizeof(u32);
}
@ -497,15 +502,8 @@ 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);
struct host1x_firewall fw;
DECLARE_BITMAP(waitchk_mask, host1x_syncpt_nb_pts(host));
fw.job = job;
fw.dev = dev;
fw.reloc = job->relocarray;
fw.num_relocs = job->num_relocs;
fw.class = 0;
bitmap_zero(waitchk_mask, host1x_syncpt_nb_pts(host));
for (i = 0; i < job->num_waitchk; i++) {
u32 syncpt_id = job->waitchk[i].syncpt_id;
@ -536,20 +534,11 @@ int host1x_job_pin(struct host1x_job *job, struct device *dev)
if (job->gathers[j].bo == g->bo)
job->gathers[j].handled = true;
err = 0;
if (IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL))
err = validate(&fw, g);
err = do_relocs(job, g->bo);
if (err)
dev_err(dev, "Job invalid (err=%d)\n", err);
if (!err)
err = do_relocs(job, g->bo);
if (!err)
err = do_waitchks(job, host, g->bo);
break;
err = do_waitchks(job, host, g->bo);
if (err)
break;
}