syzbot


KASAN: use-after-free Read in hci_req_sync_complete

Status: upstream: reported on 2024/06/16 08:56
Reported-by: syzbot+3307ad8a61e27fffc649@syzkaller.appspotmail.com
First crash: 30d, last: 30d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in hci_req_sync_complete bluetooth 8 14d 38d 0/27 upstream: reported on 2024/06/07 22:46

Sample crash report:
Bluetooth: hci0: unexpected cc 0x0c38 length: 249 > 2
Bluetooth: hci4: unexpected cc 0x0c23 length: 249 > 4
==================================================================
BUG: KASAN: use-after-free in skb_release_all net/core/skbuff.c:855 [inline]
BUG: KASAN: use-after-free in __kfree_skb net/core/skbuff.c:870 [inline]
BUG: KASAN: use-after-free in kfree_skb_reason+0x15b/0x390 net/core/skbuff.c:893
Read of size 8 at addr ffff888018644710 by task kworker/u5:1/3567

CPU: 1 PID: 3567 Comm: kworker/u5:1 Not tainted 6.1.93-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: hci0 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 skb_release_all net/core/skbuff.c:855 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 kfree_skb_reason+0x15b/0x390 net/core/skbuff.c:893
 kfree_skb include/linux/skbuff.h:1220 [inline]
 hci_req_sync_complete+0xee/0x280 net/bluetooth/hci_request.c:109
 hci_event_packet+0xc49/0x1510 net/bluetooth/hci_event.c:7601
 hci_rx_work+0x3cd/0xce0 net/bluetooth/hci_core.c:4129
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Allocated by task 3567:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 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+0x10c/0x2d0 mm/slub.c:3422
 skb_clone+0x1e5/0x360 net/core/skbuff.c:1660
 hci_send_cmd_sync net/bluetooth/hci_core.c:4178 [inline]
 hci_cmd_work+0x296/0x660 net/bluetooth/hci_core.c:4198
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Freed by task 3566:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 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+0x292/0x510 mm/slub.c:3683
 kfree_skb include/linux/skbuff.h:1220 [inline]
 __hci_req_sync+0x626/0x940 net/bluetooth/hci_request.c:184
 hci_req_sync+0xa5/0xc0 net/bluetooth/hci_request.c:206
 hci_dev_cmd+0x2fc/0xa30 net/bluetooth/hci_core.c:790
 sock_do_ioctl+0x152/0x450 net/socket.c:1204
 sock_ioctl+0x47f/0x770 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888018644640
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 208 bytes inside of
 240-byte region [ffff888018644640, ffff888018644730)

The buggy address belongs to the physical page:
page:ffffea0000619100 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888018644140 pfn:0x18644
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea00006af880 dead000000000004 ffff888014654500
raw: ffff888018644140 00000000800c000a 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 3003, tgid 3003 (udevadm), ts 14729401349, free_ts 14683269330
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513
 prep_new_page mm/page_alloc.c:2520 [inline]
 get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5547
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 kmem_cache_alloc_node+0x1cf/0x310 mm/slub.c:3443
 __alloc_skb+0xde/0x670 net/core/skbuff.c:505
 alloc_skb include/linux/skbuff.h:1271 [inline]
 alloc_uevent_skb+0x74/0x220 lib/kobject_uevent.c:290
 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline]
 kobject_uevent_net_broadcast+0x2e5/0x560 lib/kobject_uevent.c:409
 kobject_uevent_env+0x576/0x8c0 lib/kobject_uevent.c:593
 kobject_synth_uevent+0x4eb/0xae0 lib/kobject_uevent.c:208
 uevent_store+0x47/0x70 drivers/base/bus.c:581
 kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:330
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7ae/0xba0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1440 [inline]
 free_pcp_prepare mm/page_alloc.c:1490 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
 put_cpu_partial+0x17b/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x137/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc+0xa1/0x230 mm/slab_common.c:968
 kmalloc include/linux/slab.h:561 [inline]
 kernfs_fop_write_iter+0x157/0x4f0 fs/kernfs/file.c:307
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7ae/0xba0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff888018644600: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
 ffff888018644680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888018644700: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff888018644780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888018644800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/16 08:55 linux-6.1.y ae9f2a70d69e f429ab00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hci_req_sync_complete
* Struck through repros no longer work on HEAD.