| Message ID | 20190322064125.GA12551@kadam (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: shmem: Off by one in drm_gem_shmem_fault() | expand |
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 3750a982aaf6..1ee208c2c85e 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -408,7 +408,7 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) loff_t num_pages = obj->size >> PAGE_SHIFT; struct page *page; - if (vmf->pgoff > num_pages || WARN_ON_ONCE(!shmem->pages)) + if (vmf->pgoff >= num_pages || WARN_ON_ONCE(!shmem->pages)) return VM_FAULT_SIGBUS; page = shmem->pages[vmf->pgoff];
The shmem->pages[] array has "num_pages" elements so the > should be >= to prevent reading beyond the end of the array. The shmem->pages[] array is allocated in drm_gem_shmem_prime_import_sg_table(). Fixes: 2194a63a818d ("drm: Add library for shmem backed GEM objects") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)