KASAN: slab-out-of-bounds Read in soft

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
eb29d674-a4d4-4f39-a3fd-df82dc131a94	repro		❓	KASAN: slab-out-of-bounds Read in soft_cursor (2)	2026/03/08 12:34	2026/03/08 12:34	2026/03/08 12:44	31e9c887f7dc24e04b3ca70d0d54fc34141844b0

repro

❓

KASAN: slab-out-of-bounds Read in soft_cursor (2)

2026/03/08 12:34

2026/03/08 12:44

31e9c887f7dc24e04b3ca70d0d54fc34141844b0

Title	Replies (including bot)	Last reply
[syzbot] Monthly fbdev report (Feb 2026)	0 (1)	2026/02/16 07:33
[syzbot] Monthly fbdev report (Dec 2025)	0 (1)	2025/12/16 01:32
[syzbot] [fbdev?] KASAN: slab-out-of-bounds Read in soft_cursor (2)	0 (1)	2025/09/22 12:50

Title

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Last reply

[syzbot] Monthly fbdev report (Feb 2026)

0 (1)

2026/02/16 07:33

[syzbot] Monthly fbdev report (Dec 2025)

0 (1)

2025/12/16 01:32

[syzbot] [fbdev?] KASAN: slab-out-of-bounds Read in soft_cursor (2)

0 (1)

2025/09/22 12:50

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-6.1	KASAN: slab-out-of-bounds Read in soft_cursor	17				1	5h57m	5h57m	0/3	upstream: reported on 2026/07/24 00:48
linux-4.19	KASAN: slab-out-of-bounds Read in soft_cursor (2)	17	C		done	8	1888d	2010d	1/1	fixed on 2021/06/23 17:43
linux-4.14	KASAN: slab-out-of-bounds Read in soft_cursor	17	C		unreliable	57	1893d	2424d	0/1	upstream: reported C repro on 2019/12/03 14:54
linux-4.19	KASAN: slab-out-of-bounds Read in soft_cursor	17	C		done	61	2086d	2424d	1/1	fixed on 2020/12/05 19:30
upstream	KASAN: slab-out-of-bounds Read in soft_cursor fbdev	17	C	done		218	2114d	2423d	15/29	fixed on 2020/11/16 12:12
linux-5.15	KASAN: null-ptr-deref Read in soft_cursor origin:lts-only	11	syz		error	1	1152d	1153d	0/3	auto-obsoleted due to no activity on 2024/12/24 15:39
linux-4.14	KASAN: use-after-free Read in soft_cursor	19	C		inconclusive	7	1912d	2423d	0/1	upstream: reported C repro on 2019/12/04 13:11
upstream	general protection fault in soft_cursor fbdev	11	C			3	1154d	1154d	22/29	fixed on 2023/07/01 16:05
upstream	KASAN: global-out-of-bounds Read in soft_cursor (3) fbdev	17				1	38d	34d	0/29	moderation: reported on 2026/06/19 17:21
upstream	KASAN: global-out-of-bounds Read in soft_cursor (2) fbdev	17				1	517d	513d	0/29	auto-obsoleted due to no activity on 2025/05/23 01:13
linux-4.19	KASAN: global-out-of-bounds Read in soft_cursor	17	C		done	22	1886d	2353d	1/1	fixed on 2021/06/24 08:01
linux-4.14	KASAN: global-out-of-bounds Read in soft_cursor	17	C		error	19	1413d	2412d	0/1	upstream: reported C repro on 2019/12/16 00:09
upstream	KASAN: global-out-of-bounds Read in soft_cursor fbdev	17				11	2190d	2415d	0/29	auto-closed as invalid on 2020/11/22 03:01

================================================================== BUG: KASAN: slab-out-of-bounds in soft_cursor+0x458/0xa10 drivers/video/fbdev/core/softcursor.c:70 Read of size 26 at addr ffff888026dbe2cc by task syz.3.1565/16817 CPU: 0 UID: 0 PID: 16817 Comm: syz.3.1565 Not tainted syzkaller #0 PREEMPT(full) 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+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:194 [inline] kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:200 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105 soft_cursor+0x458/0xa10 drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0xe8c/0x17e0 drivers/video/fbdev/core/bitblit.c:395 fbcon_cursor+0x40c/0x5a0 drivers/video/fbdev/core/fbcon.c:1357 hide_cursor+0x87/0x220 drivers/tty/vt/vt.c:855 do_con_write+0x240c/0x8290 drivers/tty/vt/vt.c:3204 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3565 process_output_block drivers/tty/n_tty.c:561 [inline] n_tty_write+0x41e/0x11e0 drivers/tty/n_tty.c:2377 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x503/0x9b0 drivers/tty/tty_io.c:1081 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7d3/0x11d0 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe69a18f7c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe69b094038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe69a3e5fa0 RCX: 00007fe69a18f7c9 RDX: 0000000000001006 RSI: 0000200000001040 RDI: 0000000000000004 RBP: 00007fe69a213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe69a3e6038 R14: 00007fe69a3e5fa0 R15: 00007fffeee020b8 </TASK> Allocated by task 13006: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5650 [inline] __kmalloc_noprof+0x32f/0x880 mm/slub.c:5662 kmalloc_noprof include/linux/slab.h:961 [inline] fbcon_set_font+0x42e/0xc90 drivers/video/fbdev/core/fbcon.c:2538 con_font_set drivers/tty/vt/vt.c:4919 [inline] con_font_op+0x77e/0x1040 drivers/tty/vt/vt.c:4959 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:472 [inline] vt_ioctl+0x48f/0x30a0 drivers/tty/vt/vt_ioctl.c:743 tty_ioctl+0x661/0x1680 drivers/tty/tty_io.c:2792 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888026dbc000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2236 bytes to the right of allocated 6672-byte region [ffff888026dbc000, ffff888026dbda10) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26db8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b443180 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b443180 dead000000000100 dead000000000122 head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea00009b6e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5298, tgid 5298 (kworker/u33:1), ts 65073586911, free_ts 65066097360 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5178 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3059 [inline] allocate_slab mm/slub.c:3232 [inline] new_slab+0x24a/0x360 mm/slub.c:3286 ___slab_alloc+0xd79/0x1a50 mm/slub.c:4655 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] __kmalloc_cache_noprof+0x477/0x780 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] __hci_conn_add+0x14f/0x1af0 net/bluetooth/hci_conn.c:959 hci_conn_add_unset+0x6d/0x100 net/bluetooth/hci_conn.c:1072 le_conn_complete_evt+0x657/0x2150 net/bluetooth/hci_event.c:5673 hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5825 hci_le_meta_evt+0x357/0x5e0 net/bluetooth/hci_event.c:7278 hci_event_func net/bluetooth/hci_event.c:7586 [inline] hci_event_packet+0x685/0x11c0 net/bluetooth/hci_event.c:7643 hci_rx_work+0x2c9/0xeb0 net/bluetooth/hci_core.c:4076 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 page last free pid 5955 tgid 5950 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901 discard_slab mm/slub.c:3330 [inline] __put_partials+0x130/0x170 mm/slub.c:3876 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_node_noprof+0x28a/0x770 mm/slub.c:5340 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1383 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:510 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:496 [inline] vhci_write+0xc1/0x480 drivers/bluetooth/hci_vhci.c:616 do_iter_readv_writev+0x662/0x9e0 fs/read_write.c:827 vfs_writev+0x35f/0xde0 fs/read_write.c:1057 do_writev+0x132/0x340 fs/read_write.c:1103 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888026dbe180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888026dbe200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888026dbe280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888026dbe300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888026dbe380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================

Crashes (9):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Assets (help?)	Manager	Title
2025/11/29 02:55	upstream	e538109ac71d	d1b870e1	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: slab-out-of-bounds Read in soft_cursor
2025/09/15 23:41	upstream	f83ec76bf285	e2beed91	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: slab-out-of-bounds Read in soft_cursor
2025/09/26 13:23	linux-next	8e2755d7779a	0abd0691	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci-upstream-rust-kasan-gce	KASAN: slab-out-of-bounds Read in soft_cursor
2026/01/16 09:58	upstream	603c05a1639f	d6526ea3	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-selinux-root	KASAN: global-out-of-bounds Read in soft_cursor
2025/11/20 01:24	upstream	8b690556d8fe	26ee5237	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-selinux-root	KASAN: global-out-of-bounds Read in soft_cursor
2025/12/06 20:34	upstream	416f99c3b16f	d1b870e1	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream-386	KASAN: global-out-of-bounds Read in soft_cursor
2025/12/06 20:08	upstream	416f99c3b16f	d1b870e1	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream-386	KASAN: global-out-of-bounds Read in soft_cursor
2025/10/20 12:45	upstream	211ddde0823f	1c8c8cd8	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream-386	KASAN: global-out-of-bounds Read in soft_cursor
2026/02/03 02:42	git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci	59e4d31a0470	d78927dd	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci-upstream-gce-arm64	KASAN: global-out-of-bounds Read in soft_cursor

Crashes (9):

Assets (help?)