diff options
| author | Christian A. Ehrhardt <lk@c--e.de> | 2026-06-22 23:57:17 +0200 |
|---|---|---|
| committer | Boris Brezillon <boris.brezillon@collabora.com> | 2026-08-04 15:51:25 +0200 |
| commit | 617bbd08714857c1613d7c550d43a9092ec0fb97 (patch) | |
| tree | 84d9ea877a103f942d66a4b224c45d7303443df4 /drivers/gpu | |
| parent | 4da94744707b27a3ae1197bdd7127da4505dc5b1 (diff) | |
drm/shmem_helper: Check VMA boundaries for PMD mappings
In the ->huge_fault handler do not install a PMD huge page
mapping if the huge page exceeds the boundaries of the VMA.
All other ->huge_fault handlers have similar checks and the
resulting mapping will trigger a VM_BUG_ON_VMA() if it ever
reaches copy_pmd_range().
Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: stable@vger.kernel.org
Fixes: fc3bbf34e643 ("drm/shmem-helper: Fix huge page mapping in fault handler")
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patch.msgid.link/20260622215718.1532689-1-lk@c--e.de
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_gem_shmem_helper.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index c989459eb215..00807039f8d7 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -597,9 +597,13 @@ static vm_fault_t try_insert_pfn(struct vm_fault *vmf, unsigned int order, #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP } else if (order == PMD_ORDER) { unsigned long paddr = pfn << PAGE_SHIFT; + struct vm_area_struct *vma = vmf->vma; + unsigned long start = ALIGN_DOWN(vmf->address, PMD_SIZE); + unsigned long end = start + PMD_SIZE; + bool in_range = vma->vm_start <= start && end <= vma->vm_end; bool aligned = (vmf->address & ~PMD_MASK) == (paddr & ~PMD_MASK); - if (aligned && + if (aligned && in_range && folio_test_pmd_mappable(page_folio(pfn_to_page(pfn)))) { vm_fault_t ret; |