syzbot


KASAN: use-after-free Read in tcp_retransmit_timer (2)

Status: upstream: reported on 2023/10/23 18:56
Reported-by: syzbot+9bd95114d8474cd0dfa5@syzkaller.appspotmail.com
First crash: 127d, last: 1d17h
Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 KASAN: use-after-free Read in tcp_retransmit_timer (3) 1 485d 485d 0/1 auto-obsoleted due to no activity on 2023/02/27 17:38
linux-4.14 KASAN: slab-out-of-bounds Read in tcp_retransmit_timer 5 1025d 1100d 0/1 auto-closed as invalid on 2021/09/06 04:07
linux-4.19 KASAN: use-after-free Read in tcp_retransmit_timer 2 1524d 1525d 0/1 auto-closed as invalid on 2020/04/25 09:53
upstream KASAN: use-after-free Read in tcp_retransmit_timer (2) net 1 1808d 1808d 0/26 closed as invalid on 2019/04/19 21:45
upstream KASAN: use-after-free Read in tcp_retransmit_timer (5) net C unreliable 16000 453d 1465d 22/26 fixed on 2023/02/24 13:50
linux-4.19 KASAN: use-after-free Read in tcp_retransmit_timer (2) 6 954d 1121d 0/1 auto-closed as invalid on 2021/11/16 03:14
upstream KASAN: use-after-free Read in tcp_retransmit_timer (3) net 5 1720d 1740d 0/26 closed as invalid on 2019/07/01 18:06
upstream KASAN: use-after-free Read in tcp_retransmit_timer net 4 1851d 1965d 0/26 closed as invalid on 2019/03/10 18:51
linux-4.19 KASAN: slab-out-of-bounds Read in tcp_retransmit_timer 9 632d 811d 0/1 auto-obsoleted due to no activity on 2022/10/04 11:51
upstream KASAN: use-after-free Read in tcp_retransmit_timer (4) net 2 1665d 1665d 0/26 closed as invalid on 2019/10/03 04:18
linux-5.15 KASAN: use-after-free Read in tcp_retransmit_timer 76 237d 344d 0/3 auto-obsoleted due to no activity on 2023/09/14 02:10

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in tcp_retransmit_timer+0x6df/0x2810 net/ipv4/tcp_timer.c:531
Read of size 8 at addr ffff888022fe5118 by task kworker/u4:23/5335

CPU: 0 PID: 5335 Comm: kworker/u4:23 Not tainted 5.15.149-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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
 tcp_retransmit_timer+0x6df/0x2810 net/ipv4/tcp_timer.c:531
 tcp_write_timer_handler+0x1f7/0x9c0 net/ipv4/tcp_timer.c:644
 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:664
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1737
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:375 [inline]
RIP: 0010:__rcu_read_lock+0x2b/0xb0 kernel/rcu/tree_plugin.h:398
Code: 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 4c 8b 3d 28 ce 96 7e 49 81 c7 3c 04 00 00 4c 89 fb 48 c1 eb 03 42 0f b6 04 33 <84> c0 75 2f 41 8b 2f ff c5 42 0f b6 04 33 84 c0 75 38 41 89 2f 42
RSP: 0018:ffffc9000442fbd0 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: 1ffff1100f71043f RCX: ffff88807b881dc0
RDX: 0000000000000000 RSI: ffffffff8a8b27a0 RDI: ffffffff8ad88e40
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1bc7746
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000000002a8
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807b8821fc
 rcu_read_lock include/linux/rcupdate.h:694 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0xbc/0x5b0 net/batman-adv/network-coding.c:723
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Allocated by task 3544:
 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_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 net_alloc net/core/net_namespace.c:405 [inline]
 copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:460
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x580/0xb20 kernel/fork.c:3101
 __do_sys_unshare kernel/fork.c:3175 [inline]
 __se_sys_unshare kernel/fork.c:3173 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3173
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 5335:
 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]
 kmem_cache_free+0x91/0x1f0 mm/slub.c:3515
 net_free net/core/net_namespace.c:434 [inline]
 cleanup_net+0xab5/0xb60 net/core/net_namespace.c:617
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 insert_work+0x54/0x3e0 kernel/workqueue.c:1366
 __queue_work+0x963/0xd00 kernel/workqueue.c:1532
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1559
 xfrm_state_find+0x28fd/0x2f10 net/xfrm/xfrm_state.c:1184
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2391 [inline]
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2436 [inline]
 xfrm_resolve_and_create_bundle+0x696/0x2950 net/xfrm/xfrm_policy.c:2729
 xfrm_lookup_with_ifid+0x31a/0x2420 net/xfrm/xfrm_policy.c:3063
 xfrm_lookup net/xfrm/xfrm_policy.c:3192 [inline]
 xfrm_lookup_route+0x38/0x1a0 net/xfrm/xfrm_policy.c:3203
 udp_sendmsg+0x19f1/0x2d90 net/ipv4/udp.c:1232
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
 __sys_sendmmsg+0x2bf/0x560 net/socket.c:2571
 __do_sys_sendmmsg net/socket.c:2600 [inline]
 __se_sys_sendmmsg net/socket.c:2597 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Second to last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 insert_work+0x54/0x3e0 kernel/workqueue.c:1366
 __queue_work+0x963/0xd00 kernel/workqueue.c:1532
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1559
 xfrm_state_find+0x28fd/0x2f10 net/xfrm/xfrm_state.c:1184
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2391 [inline]
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2436 [inline]
 xfrm_resolve_and_create_bundle+0x696/0x2950 net/xfrm/xfrm_policy.c:2729
 xfrm_lookup_with_ifid+0x31a/0x2420 net/xfrm/xfrm_policy.c:3063
 xfrm_lookup net/xfrm/xfrm_policy.c:3192 [inline]
 xfrm_lookup_route+0x38/0x1a0 net/xfrm/xfrm_policy.c:3203
 udp_sendmsg+0x19f1/0x2d90 net/ipv4/udp.c:1232
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
 __sys_sendmmsg+0x2bf/0x560 net/socket.c:2571
 __do_sys_sendmmsg net/socket.c:2600 [inline]
 __se_sys_sendmmsg net/socket.c:2597 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff888022fe4ec0
 which belongs to the cache net_namespace of size 6464
The buggy address is located 600 bytes inside of
 6464-byte region [ffff888022fe4ec0, ffff888022fe6800)
The buggy address belongs to the page:
page:ffffea00008bf800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22fe0
head:ffffea00008bf800 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011dea3c0
raw: 0000000000000000 0000000000040004 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3534, ts 189245056572, free_ts 189241539095
 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:5421
 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+0x18e/0x280 mm/slub.c:3233
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 net_alloc net/core/net_namespace.c:405 [inline]
 copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:460
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x580/0xb20 kernel/fork.c:3101
 __do_sys_unshare kernel/fork.c:3175 [inline]
 __se_sys_unshare kernel/fork.c:3173 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3173
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
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_nonslab_page+0xe4/0x150 mm/slub.c:3535
 kfree+0x1cf/0x270 mm/slub.c:4556
 skb_free_head net/core/skbuff.c:655 [inline]
 skb_release_data+0x73a/0x8a0 net/core/skbuff.c:677
 skb_release_all net/core/skbuff.c:742 [inline]
 __kfree_skb net/core/skbuff.c:756 [inline]
 consume_skb+0xa3/0x140 net/core/skbuff.c:914
 skb_free_datagram+0x24/0xe0 net/core/datagram.c:325
 netlink_recvmsg+0x5ef/0x1190 net/netlink/af_netlink.c:2002
 ____sys_recvmsg+0x286/0x530
 ___sys_recvmsg+0x1ec/0x690 net/socket.c:2692
 __sys_recvmsg net/socket.c:2722 [inline]
 __do_sys_recvmsg net/socket.c:2732 [inline]
 __se_sys_recvmsg net/socket.c:2729 [inline]
 __x64_sys_recvmsg+0x1dc/0x2b0 net/socket.c:2729
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff888022fe5000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888022fe5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888022fe5100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888022fe5180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888022fe5200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	41 57                	push   %r15
   2:	41 56                	push   %r14
   4:	53                   	push   %rbx
   5:	49 be 00 00 00 00 00 	movabs $0xdffffc0000000000,%r14
   c:	fc ff df
   f:	65 4c 8b 3d 28 ce 96 	mov    %gs:0x7e96ce28(%rip),%r15        # 0x7e96ce3f
  16:	7e
  17:	49 81 c7 3c 04 00 00 	add    $0x43c,%r15
  1e:	4c 89 fb             	mov    %r15,%rbx
  21:	48 c1 eb 03          	shr    $0x3,%rbx
  25:	42 0f b6 04 33       	movzbl (%rbx,%r14,1),%eax
* 2a:	84 c0                	test   %al,%al <-- trapping instruction
  2c:	75 2f                	jne    0x5d
  2e:	41 8b 2f             	mov    (%r15),%ebp
  31:	ff c5                	inc    %ebp
  33:	42 0f b6 04 33       	movzbl (%rbx,%r14,1),%eax
  38:	84 c0                	test   %al,%al
  3a:	75 38                	jne    0x74
  3c:	41 89 2f             	mov    %ebp,(%r15)
  3f:	42                   	rex.X

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/26 20:29 linux-5.15.y 458ce51d0356 da36a36b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/02/15 19:24 linux-5.15.y 6139f2a02fe0 fd39cf6f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/02/09 14:34 linux-5.15.y 6139f2a02fe0 7f07e9b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/01/11 10:47 linux-5.15.y 26c690eff0a5 00f3cc59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2023/10/23 18:55 linux-5.15.y 00c03985402e 989a3687 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/01/29 12:41 linux-5.15.y 6139f2a02fe0 991a98f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in tcp_retransmit_timer
* Struck through repros no longer work on HEAD.