syzbot


KASAN: invalid-free in hci_req_sync_complete

Status: upstream: reported on 2024/04/23 17:36
Reported-by: syzbot+c68cf32df83b2b1717ff@syzkaller.appspotmail.com
First crash: 56d, last: 22d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: invalid-free in hci_req_sync_complete bluetooth 141 22h06m 57d 0/27 upstream: reported on 2024/04/22 06:47

Sample crash report:
Bluetooth: hci4: unexpected cc 0x1001 length: 249 > 9
==================================================================
BUG: KASAN: double-free in kfree_skbmem+0x10c/0x19c
Free of addr ffff0000ed5d5280 by task kworker/u5:6/4262

CPU: 0 PID: 4262 Comm: kworker/u5:6 Not tainted 6.1.92-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: hci2 hci_rx_work
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x174/0x4c0 mm/kasan/report.c:395
 kasan_report_invalid_free+0xc4/0x114 mm/kasan/report.c:460
 ____kasan_slab_free+0x170/0x1c0 mm/kasan/common.c:225
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x2f0/0x588 mm/slub.c:3683
 kfree_skbmem+0x10c/0x19c
 __kfree_skb net/core/skbuff.c:871 [inline]
 kfree_skb_reason+0x1ac/0x47c net/core/skbuff.c:893
 kfree_skb include/linux/skbuff.h:1220 [inline]
 hci_req_sync_complete+0xcc/0x258 net/bluetooth/hci_request.c:109
 hci_event_packet+0xbd4/0x109c net/bluetooth/hci_event.c:7601
 hci_rx_work+0x318/0xa68 net/bluetooth/hci_core.c:4129
 process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292
 worker_thread+0x8e4/0xfec kernel/workqueue.c:2439
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864

Allocated by task 4254:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x74/0x458 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x230/0x37c mm/slub.c:3422
 skb_clone+0x19c/0x304 net/core/skbuff.c:1660
 hci_send_cmd_sync net/bluetooth/hci_core.c:4178 [inline]
 hci_cmd_work+0x174/0x568 net/bluetooth/hci_core.c:4198
 process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292
 worker_thread+0x8e4/0xfec kernel/workqueue.c:2439
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864

Freed by task 4257:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x2f0/0x588 mm/slub.c:3683
 kfree_skbmem+0x10c/0x19c
 __kfree_skb net/core/skbuff.c:871 [inline]
 kfree_skb_reason+0x1ac/0x47c net/core/skbuff.c:893
 kfree_skb include/linux/skbuff.h:1220 [inline]
 __hci_req_sync+0x4fc/0x7ac net/bluetooth/hci_request.c:184
 hci_req_sync+0xa4/0xd0 net/bluetooth/hci_request.c:206
 hci_dev_cmd+0x330/0x90c net/bluetooth/hci_core.c:790
 hci_sock_ioctl+0x4b8/0x82c net/bluetooth/hci_sock.c:1096
 sock_do_ioctl+0x134/0x2dc net/socket.c:1204
 sock_ioctl+0x4ec/0x858 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000ed5d5280
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 0 bytes inside of
 240-byte region [ffff0000ed5d5280, ffff0000ed5d5370)

The buggy address belongs to the physical page:
page:0000000082ab2715 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12d5d5
flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000200 0000000000000000 dead000000000122 ffff0000c0b76480
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ed5d5180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000ed5d5200: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
>ffff0000ed5d5280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff0000ed5d5300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff0000ed5d5380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/27 13:16 linux-6.1.y 88690811da69 761766e6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: invalid-free in hci_req_sync_complete
2024/04/23 17:35 linux-6.1.y 6741e066ec76 21339d7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: invalid-free in hci_req_sync_complete
* Struck through repros no longer work on HEAD.