syzkaller found a bug:
BUG: KASAN: vmalloc-out-of-bounds in tpg_fill_plane_pattern drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2608 [inline] BUG: KASAN: vmalloc-out-of-bounds in tpg_fill_plane_buffer+0x1a9c/0x5af0 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2705 Write of size 1440 at addr ffffc9000d0ffda0 by task vivid-000-vid-c/5304
CPU: 0 UID: 0 PID: 5304 Comm: vivid-000-vid-c Not tainted 6.14.0-rc2-syzkaller-00039-g09fbf3d50205 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 tpg_fill_plane_pattern drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2608 [inline] tpg_fill_plane_buffer+0x1a9c/0x5af0 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2705 vivid_fillbuff drivers/media/test-drivers/vivid/vivid-kthread-cap.c:470 [inline] vivid_thread_vid_cap_tick+0xf8e/0x60d0 drivers/media/test-drivers/vivid/vivid-kthread-cap.c:629 vivid_thread_vid_cap+0x8aa/0xf30 drivers/media/test-drivers/vivid/vivid-kthread-cap.c:767 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK>
The composition size cannot be larger than the size of fmt_cap_rect. So execute v4l2_rect_map_inside() even if has_compose_cap == 0.
Fixes: 94a7ad928346 ("media: vivid: fix compose size exceed boundary") Cc: stable@vger.kernel.org Reported-by: syzbot+365005005522b70a36f2@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?id=8ed8e8cc30cbe0d86c9a25bd1d6a5775129b8ea... Signed-off-by: Denis Arefev arefev@swemel.ru --- drivers/media/test-drivers/vivid/vivid-vid-cap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/test-drivers/vivid/vivid-vid-cap.c b/drivers/media/test-drivers/vivid/vivid-vid-cap.c index b166d90177c6..df5d1c2a42ef 100644 --- a/drivers/media/test-drivers/vivid/vivid-vid-cap.c +++ b/drivers/media/test-drivers/vivid/vivid-vid-cap.c @@ -946,8 +946,8 @@ int vivid_vid_cap_s_selection(struct file *file, void *fh, struct v4l2_selection if (dev->has_compose_cap) { v4l2_rect_set_min_size(compose, &min_rect); v4l2_rect_set_max_size(compose, &max_rect); - v4l2_rect_map_inside(compose, &fmt); } + v4l2_rect_map_inside(compose, &fmt); dev->fmt_cap_rect = fmt; tpg_s_buf_height(&dev->tpg, fmt.height); } else if (dev->has_compose_cap) {