| Message ID | 20170630075915.crhfqqmjaxq34awz@mwanda (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jun 30, 2017 at 10:59:15AM +0300, Dan Carpenter wrote: > 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 <dan.carpenter@oracle.com> Indeed. Thanks for the catch. Acked-by: Jordan Crouse <jcrouse@codeaurora.org> > diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c > index 6bfca7470141..8095658e8cb4 100644 > --- 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_create(struct drm_device *dev, > 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; > _______________________________________________ > Freedreno mailing list > Freedreno@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/freedreno
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c index 6bfca7470141..8095658e8cb4 100644 --- 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_create(struct drm_device *dev, 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;
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 <dan.carpenter@oracle.com>