syzbot


KASAN: use-after-free Read in __lock_sock

Status: upstream: reported on 2024/10/05 02:50
Reported-by: syzbot+f93e987263fd107189e5@syzkaller.appspotmail.com
First crash: 17d, last: 1d20h
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 KASAN: use-after-free Read in __lock_sock syz done 2 1821d 1822d 1/1 fixed on 2019/12/18 04:11
upstream KASAN: use-after-free Read in __lock_sock sctp syz done error 26 1350d 2166d 20/28 fixed on 2022/03/08 16:11
linux-4.19 KASAN: use-after-free Read in __lock_sock (2) 1 1724d 1724d 0/1 auto-closed as invalid on 2020/06/01 06:17
linux-4.14 KASAN: use-after-free Read in __lock_sock syz inconclusive 1 1595d 1715d 0/1 upstream: reported syz repro on 2020/02/11 04:34
upstream KASAN: slab-use-after-free Read in __lock_sock bluetooth C 1 335d 335d 0/28 auto-obsoleted due to no activity on 2024/03/01 14:18
upstream KASAN: slab-use-after-free Read in __lock_sock (2) bluetooth C 5 114d 128d 0/28 auto-obsoleted due to no activity on 2024/10/08 16:07

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x74/0x1ff0 kernel/locking/lockdep.c:4882
Read of size 8 at addr ffff88806064b0a0 by task kworker/u5:7/3585

CPU: 1 PID: 3585 Comm: kworker/u5:7 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: hci6 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 __lock_acquire+0x74/0x1ff0 kernel/locking/lockdep.c:4882
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:368 [inline]
 __lock_sock+0x1d0/0x320 net/core/sock.c:2701
 lock_sock_nested+0x9c/0x100 net/core/sock.c:3255
 lock_sock include/net/sock.h:1676 [inline]
 l2cap_sock_recv_cb+0x4c/0x1e0 net/bluetooth/l2cap_sock.c:1499
 l2cap_conless_channel net/bluetooth/l2cap_core.c:7769 [inline]
 l2cap_recv_frame+0x1299/0x8ae0 net/bluetooth/l2cap_core.c:7823
 hci_acldata_packet net/bluetooth/hci_core.c:4969 [inline]
 hci_rx_work+0x48f/0x990 net/bluetooth/hci_core.c:5160
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 4264:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 __kmalloc+0x168/0x300 mm/slub.c:4407
 kmalloc include/linux/slab.h:596 [inline]
 sk_prot_alloc+0xe0/0x200 net/core/sock.c:1863
 sk_alloc+0x35/0x310 net/core/sock.c:1916
 l2cap_sock_alloc+0x34/0x1d0 net/bluetooth/l2cap_sock.c:1861
 l2cap_sock_create+0x10d/0x1c0 net/bluetooth/l2cap_sock.c:1907
 bt_sock_create+0x159/0x220 net/bluetooth/af_bluetooth.c:130
 __sock_create+0x460/0x8d0 net/socket.c:1486
 sock_create net/socket.c:1537 [inline]
 __sys_socket+0x132/0x370 net/socket.c:1579
 __do_sys_socket net/socket.c:1588 [inline]
 __se_sys_socket net/socket.c:1586 [inline]
 __x64_sys_socket+0x76/0x80 net/socket.c:1586
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 4268:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 sk_prot_free net/core/sock.c:1899 [inline]
 __sk_destruct+0x58e/0x840 net/core/sock.c:1985
 l2cap_sock_release+0x157/0x1d0 net/bluetooth/l2cap_sock.c:1429
 __sock_release net/socket.c:649 [inline]
 sock_close+0xcd/0x230 net/socket.c:1336
 __fput+0x3fe/0x8e0 fs/file_table.c:280
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 get_signal+0x143a/0x14e0 kernel/signal.c:2669
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88806064b000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 160 bytes inside of
 2048-byte region [ffff88806064b000, ffff88806064b800)
The buggy address belongs to the page:
page:ffffea0001819200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x60648
head:ffffea0001819200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001f93600 0000000300000003 ffff888017042000
raw: 0000000000000000 0000000080080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 3568, ts 60670884797, free_ts 16683179354
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc_trace+0x1a0/0x290 mm/slub.c:3245
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 device_create_groups_vargs drivers/base/core.c:4061 [inline]
 device_create+0x11d/0x2e0 drivers/base/core.c:4121
 mac80211_hwsim_new_radio+0x314/0x4200 drivers/net/wireless/mac80211_hwsim.c:3089
 hwsim_new_radio_nl+0xbae/0x1090 drivers/net/wireless/mac80211_hwsim.c:3950
 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0xfbd/0x14a0 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2503
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
 netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 __sys_sendto+0x564/0x720 net/socket.c:2058
 __do_sys_sendto net/socket.c:2070 [inline]
 __se_sys_sendto net/socket.c:2066 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2066
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_contig_range+0x95/0xf0 mm/page_alloc.c:9342
 destroy_args+0xfe/0x980 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x40d/0x470 mm/debug_vm_pgtable.c:1331
 do_one_initcall+0x22b/0x7a0 init/main.c:1302
 do_initcall_level+0x157/0x210 init/main.c:1375
 do_initcalls+0x49/0x90 init/main.c:1391
 kernel_init_freeable+0x425/0x5c0 init/main.c:1615
 kernel_init+0x19/0x290 init/main.c:1506
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88806064af80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806064b000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88806064b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88806064b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806064b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/08 21:34 linux-5.15.y 3a5928702e71 402f1df0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in __lock_sock
2024/10/08 17:15 linux-5.15.y 3a5928702e71 402f1df0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in __lock_sock
2024/10/05 02:49 linux-5.15.y 3a5928702e71 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in __lock_sock
2024/10/21 00:42 linux-5.15.y 584a40a22cb9 cd6fc0a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in __lock_sock
2024/10/09 05:10 linux-5.15.y 3a5928702e71 402f1df0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in __lock_sock
2024/10/07 20:30 linux-5.15.y 3a5928702e71 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in __lock_sock
* Struck through repros no longer work on HEAD.