KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (5)

KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (5)

Status: upstream: reported on 2026/07/24 20:10
Subsystems: media
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+cb43e758a4dc84dd467f@syzkaller.appspotmail.com
First crash: 13d, last: 22h18m

▶ ▼ ✨ AI Jobs (1)

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
2ad22663	assessment-security	DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (5)	2026/07/17 00:11	2026/07/17 00:11	2026/07/17 00:57	49f47391

▶ ▼ Discussions (1)

Title	Replies (including bot)	Last reply
[syzbot] [media?] KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (5)	0 (1)	2026/07/24 20:10

▶ ▼ Similar bugs (10)

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-6.1	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer	21				3	409d	445d	0/3	auto-obsoleted due to no activity on 2025/09/22 17:26
upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (4) prio:normal media	21				255	13d	379d	29/29	fixed on 2026/07/15 08:27
upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (3) media	21	syz, C			271	387d	741d	29/29	fixed on 2025/07/08 00:33
upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer media	21				1	2383d	2383d	0/29	auto-closed as invalid on 2020/05/17 19:44
linux-5.15	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer	21				1	1196d	1196d	0/3	auto-obsoleted due to no activity on 2023/08/17 04:37
linux-6.6	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer	21				1	34d	34d	0/2	upstream: reported on 2026/06/24 12:36
upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer (2) media	21	syz, C	inconclusive	done	14	1275d	1787d	22/29	fixed on 2023/02/24 13:51
linux-4.19	BUG: unable to handle kernel paging request in tpg_fill_plane_buffer (2)	8	syz		error	8	1321d	1821d	0/1	upstream: reported syz repro on 2021/08/02 00:51
linux-4.14	BUG: unable to handle kernel paging request in tpg_fill_plane_buffer (2)	8				1	1655d	1655d	0/1	auto-closed as invalid on 2022/05/15 07:48
upstream	BUG: unable to handle kernel paging request in tpg_fill_plane_buffer (2) media	8				1	1205d	1201d	0/29	auto-obsoleted due to no activity on 2023/07/09 12:46

Sample crash report:

==================================================================
BUG: KASAN: vmalloc-out-of-bounds in tpg_fill_plane_pattern drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:-1 [inline]
BUG: KASAN: vmalloc-out-of-bounds in tpg_fill_plane_buffer+0x1b4f/0x5ea0 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2705
Write of size 1280 at addr ffffc9000318cb40 by task vivid-000-vid-c/23857

CPU: 0 UID: 0 PID: 23857 Comm: vivid-000-vid-c Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200
 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106
 tpg_fill_plane_pattern drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:-1 [inline]
 tpg_fill_plane_buffer+0x1b4f/0x5ea0 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+0x115c/0x6340 drivers/media/test-drivers/vivid/vivid-kthread-cap.c:629
 vivid_thread_vid_cap+0x927/0x11e0 drivers/media/test-drivers/vivid/vivid-kthread-cap.c:767
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to a 3-page vmalloc region starting at 0xffffc9000318a000 allocated at vb2_vmalloc_alloc+0xef/0x360 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880349b6690 pfn:0x349b6
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff8880349b6690 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 23856, tgid 23852 (syz.1.5596), ts 1295989549275, free_ts 1295989478532
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 __alloc_pages_noprof+0x10/0x100 mm/page_alloc.c:5338
 alloc_pages_bulk_noprof+0x5f5/0x7b0 mm/page_alloc.c:5230
 alloc_pages_bulk_mempolicy_noprof+0x34b/0x1690 mm/mempolicy.c:2798
 vm_area_alloc_pages mm/vmalloc.c:3714 [inline]
 __vmalloc_area_node mm/vmalloc.c:3892 [inline]
 __vmalloc_node_range_noprof+0xb1d/0x1730 mm/vmalloc.c:4082
 vmalloc_user_noprof+0xad/0xe0 mm/vmalloc.c:4237
 vb2_vmalloc_alloc+0xef/0x360 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47
 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:242 [inline]
 __vb2_queue_alloc+0xa0b/0x1660 drivers/media/common/videobuf2/videobuf2-core.c:523
 vb2_core_reqbufs+0xc3f/0x1470 drivers/media/common/videobuf2/videobuf2-core.c:958
 __vb2_init_fileio+0x310/0x1040 drivers/media/common/videobuf2/videobuf2-core.c:2879
 __vb2_perform_fileio+0x287/0x1660 drivers/media/common/videobuf2/videobuf2-core.c:3025
 vb2_fop_read+0x282/0x360 drivers/media/common/videobuf2/videobuf2-v4l2.c:1215
 v4l2_read+0x19c/0x2c0 drivers/media/v4l2-core/v4l2-dev.c:316
 vfs_read+0x213/0xa80 fs/read_write.c:572
page last free pid 23856 tgid 23852 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline]
 __kasan_populate_vmalloc+0x1a8/0x1c0 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:580 [inline]
 alloc_vmap_area+0xd1a/0x1420 mm/vmalloc.c:2123
 __get_vm_area_node+0x1f2/0x300 mm/vmalloc.c:3226
 __vmalloc_node_range_noprof+0x358/0x1730 mm/vmalloc.c:4042
 vmalloc_user_noprof+0xad/0xe0 mm/vmalloc.c:4237
 vb2_vmalloc_alloc+0xef/0x360 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47
 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:242 [inline]
 __vb2_queue_alloc+0xa0b/0x1660 drivers/media/common/videobuf2/videobuf2-core.c:523
 vb2_core_reqbufs+0xc3f/0x1470 drivers/media/common/videobuf2/videobuf2-core.c:958
 __vb2_init_fileio+0x310/0x1040 drivers/media/common/videobuf2/videobuf2-core.c:2879
 __vb2_perform_fileio+0x287/0x1660 drivers/media/common/videobuf2/videobuf2-core.c:3025
 vb2_fop_read+0x282/0x360 drivers/media/common/videobuf2/videobuf2-v4l2.c:1215
 v4l2_read+0x19c/0x2c0 drivers/media/v4l2-core/v4l2-dev.c:316
 vfs_read+0x213/0xa80 fs/read_write.c:572
 ksys_read+0x150/0x270 fs/read_write.c:716
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307

Memory state around the buggy address:
 ffffc9000318cf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000318cf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9000318d000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                   ^
 ffffc9000318d080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc9000318d100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================

Crashes (6):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/07/27 23:44	upstream	f5098b6bae76	4cb2b096	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-386	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer
2026/07/24 20:09	upstream	48a5a7ab8d6a	4a865b71	.config	console log	report			info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer
2026/07/23 23:29	upstream	4539944e5151	4a865b71	.config	console log	report			info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer
2026/07/19 22:28	upstream	c6859eed755d	72524a66	.config	console log	report			info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer
2026/07/18 22:24	upstream	1229e2e57a5c	72524a66	.config	console log	report			info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer
2026/07/15 14:21	upstream	58717b2a1365	a4ed0f4f	.config	console log	report			info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: vmalloc-out-of-bounds Write in tpg_fill_plane_buffer

* ~~Struck through~~ repros no longer work on HEAD.