From aabf8665c5e88deefe8b27898bad089b67f8b08a Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Tue, 17 Apr 2018 09:11:12 +0200 Subject: [PATCH 1/2] qxl: fix qxl_release_{map,unmap} s/PAGE_SIZE/PAGE_MASK/ Luckily release_offset is never larger than PAGE_SIZE, so the bug has no bad side effects and managed to stay unnoticed for years that way ... Signed-off-by: Gerd Hoffmann --- drivers/gpu/drm/qxl/qxl_ioctl.c | 4 ++-- drivers/gpu/drm/qxl/qxl_release.c | 6 +++--- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/qxl/qxl_ioctl.c b/drivers/gpu/drm/qxl/qxl_ioctl.c index e8c0b10372..ae37cfc56b 100644 --- a/drivers/gpu/drm/qxl/qxl_ioctl.c +++ b/drivers/gpu/drm/qxl/qxl_ioctl.c @@ -182,9 +182,9 @@ static int qxl_process_single_command(struct qxl_device *qdev, goto out_free_reloc; /* TODO copy slow path code from i915 */ - fb_cmd = qxl_bo_kmap_atomic_page(qdev, cmd_bo, (release->release_offset & PAGE_SIZE)); + fb_cmd = qxl_bo_kmap_atomic_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK)); unwritten = __copy_from_user_inatomic_nocache - (fb_cmd + sizeof(union qxl_release_info) + (release->release_offset & ~PAGE_SIZE), + (fb_cmd + sizeof(union qxl_release_info) + (release->release_offset & ~PAGE_MASK), u64_to_user_ptr(cmd->command), cmd->command_size); { diff --git a/drivers/gpu/drm/qxl/qxl_release.c b/drivers/gpu/drm/qxl/qxl_release.c index b223c8d0a4..91a10459da 100644 --- a/drivers/gpu/drm/qxl/qxl_release.c +++ b/drivers/gpu/drm/qxl/qxl_release.c @@ -411,10 +411,10 @@ union qxl_release_info *qxl_release_map(struct qxl_device *qdev, struct qxl_bo_list *entry = list_first_entry(&release->bos, struct qxl_bo_list, tv.head); struct qxl_bo *bo = to_qxl_bo(entry->tv.bo); - ptr = qxl_bo_kmap_atomic_page(qdev, bo, release->release_offset & PAGE_SIZE); + ptr = qxl_bo_kmap_atomic_page(qdev, bo, release->release_offset & PAGE_MASK); if (!ptr) return NULL; - info = ptr + (release->release_offset & ~PAGE_SIZE); + info = ptr + (release->release_offset & ~PAGE_MASK); return info; } @@ -426,7 +426,7 @@ void qxl_release_unmap(struct qxl_device *qdev, struct qxl_bo *bo = to_qxl_bo(entry->tv.bo); void *ptr; - ptr = ((void *)info) - (release->release_offset & ~PAGE_SIZE); + ptr = ((void *)info) - (release->release_offset & ~PAGE_MASK); qxl_bo_kunmap_atomic_page(qdev, bo, ptr); } -- 2.9.3