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KASAN: use-after-free Read in tipc_udp_xmit

Status: upstream: reported C repro on 2021/08/15 18:20
Reported-by: syzbot+88458b50d3fe169b97b5@syzkaller.appspotmail.com
First crash: 1223d, last: 670d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2021/11/08 08:26 11m bisect fix linux-4.19.y error job log
2021/10/05 03:18 42m bisect fix linux-4.19.y OK (0) job log log

Sample crash report:
Disabling bearer <udp:syz0>
New replicast peer: fe80:0000:0000:0000:0000:0000:0000:0000
Enabled bearer <udp:syz0>, priority 10
Disabling bearer <udp:syz0>
==================================================================
BUG: KASAN: use-after-free in tipc_udp_xmit+0xa7d/0xc10 net/tipc/udp_media.c:200
Read of size 8 at addr ffff88808a56a5a0 by task swapper/1/0

CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.204-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 tipc_udp_xmit+0xa7d/0xc10 net/tipc/udp_media.c:200
 tipc_udp_send_msg+0x279/0x490 net/tipc/udp_media.c:248
 tipc_bearer_xmit_skb+0x15b/0x330 net/tipc/bearer.c:518
 tipc_disc_timeout+0x855/0xc90 net/tipc/discover.c:332
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1696 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709
 __do_softirq+0x265/0x980 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 48 89 df e8 d4 59 7f f9 e9 2e ff ff ff 48 89 df e8 c7 59 7f f9 eb 82 90 90 90 90 90 e9 07 00 00 00 0f 00 2d b4 77 4e 00 fb f4 <c3> 90 e9 07 00 00 00 0f 00 2d a4 77 4e 00 f4 c3 90 90 41 56 41 55
RSP: 0018:ffff8880b5a9fd40 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13e305c RBX: dffffc0000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff8880b5a86c44
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89f182d0
R13: 1ffff11016b53fb2 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x49/0x310 arch/x86/kernel/process.c:557
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ec/0x4b0 kernel/sched/idle.c:263
 cpu_startup_entry+0xc5/0xe0 kernel/sched/idle.c:369
 start_secondary+0x435/0x5c0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

Allocated by task 8712:
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 sock_alloc_inode+0x19/0x250 net/socket.c:244
 alloc_inode+0x5d/0x180 fs/inode.c:211
 new_inode_pseudo+0x14/0xe0 fs/inode.c:911
 sock_alloc+0x3c/0x260 net/socket.c:567
 __sock_create+0xba/0x740 net/socket.c:1327
 udp_sock_create6+0xd1/0x550 net/ipv6/ip6_udp_tunnel.c:22
 udp_sock_create include/net/udp_tunnel.h:61 [inline]
 tipc_udp_enable+0xb48/0x14d0 net/tipc/udp_media.c:734
 tipc_enable_bearer+0x70f/0xbe0 net/tipc/bearer.c:317
 __tipc_nl_bearer_enable+0x2e2/0x3d0 net/tipc/bearer.c:916
 tipc_nl_bearer_enable+0x1e/0x30 net/tipc/bearer.c:925
 genl_family_rcv_msg+0x642/0xc40 net/netlink/genetlink.c:602
 genl_rcv_msg+0xbf/0x160 net/netlink/genetlink.c:627
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2457
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:638
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1911
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2225
 __sys_sendmsg net/socket.c:2263 [inline]
 __do_sys_sendmsg net/socket.c:2272 [inline]
 __se_sys_sendmsg net/socket.c:2270 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2270
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8306:
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x7f/0x260 mm/slab.c:3765
 destroy_inode+0xb9/0x110 fs/inode.c:268
 iput_final fs/inode.c:1555 [inline]
 iput+0x4f1/0x860 fs/inode.c:1581
 __sock_release net/socket.c:611 [inline]
 sock_release+0x174/0x1d0 net/socket.c:619
 cleanup_bearer+0x1bb/0x280 net/tipc/udp_media.c:775
 process_one_work+0x864/0x1570 kernel/workqueue.c:2153
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

The buggy address belongs to the object at ffff88808a56a580
 which belongs to the cache sock_inode_cache of size 992
The buggy address is located 32 bytes inside of
 992-byte region [ffff88808a56a580, ffff88808a56a960)
The buggy address belongs to the page:
page:ffffea0002295a80 count:1 mapcount:0 mapping:ffff88823b33a6c0 index:0xffff88808a56affd
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffffea0002295948 ffffea0002295ac8 ffff88823b33a6c0
raw: ffff88808a56affd ffff88808a56a100 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808a56a480: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88808a56a500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88808a56a580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88808a56a600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808a56a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	48 89 df             	mov    %rbx,%rdi
   3:	e8 d4 59 7f f9       	callq  0xf97f59dc
   8:	e9 2e ff ff ff       	jmpq   0xffffff3b
   d:	48 89 df             	mov    %rbx,%rdi
  10:	e8 c7 59 7f f9       	callq  0xf97f59dc
  15:	eb 82                	jmp    0xffffff99
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	90                   	nop
  1c:	e9 07 00 00 00       	jmpq   0x28
  21:	0f 00 2d b4 77 4e 00 	verw   0x4e77b4(%rip)        # 0x4e77dc
  28:	fb                   	sti    
  29:	f4                   	hlt    
  2a:	c3                   	retq    <-- trapping instruction
  2b:	90                   	nop
  2c:	e9 07 00 00 00       	jmpq   0x38
  31:	0f 00 2d a4 77 4e 00 	verw   0x4e77a4(%rip)        # 0x4e77dc
  38:	f4                   	hlt    
  39:	c3                   	retq   
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	41 56                	push   %r14
  3e:	41 55                	push   %r13

Crashes (22):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/08/15 23:38 linux-4.19.y 59456c9cc40c 2489ab88 .config console log report syz C ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2023/02/20 05:49 linux-4.19.y 3f8a27f9e27b bcdf85f8 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2023/02/06 23:05 linux-4.19.y 3f8a27f9e27b 0a9c11b6 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2023/02/02 08:23 linux-4.19.y 3f8a27f9e27b 9a6f477c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2023/01/23 15:07 linux-4.19.y 3f8a27f9e27b 9dfcf09c .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/12/21 05:20 linux-4.19.y 3f8a27f9e27b d3e76707 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/12/21 02:24 linux-4.19.y 3f8a27f9e27b d3e76707 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/12/15 10:30 linux-4.19.y 3f8a27f9e27b b18f0a64 .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/11/24 12:40 linux-4.19.y 3f8a27f9e27b ff68ff8f .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/08/20 06:21 linux-4.19.y 3f8a27f9e27b 26a13b38 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/08/16 17:59 linux-4.19.y 3f8a27f9e27b 7a7cb304 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/08/03 15:52 linux-4.19.y 3f8a27f9e27b 1c9013ac .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/04/25 16:46 linux-4.19.y 3f8a27f9e27b 152baedd .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/04/15 15:35 linux-4.19.y 3f8a27f9e27b 8bcc32a6 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/02/12 17:12 linux-4.19.y 3f8a27f9e27b 8b9ca619 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/01/15 23:34 linux-4.19.y 3f8a27f9e27b 723cfaf0 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2022/01/04 14:23 linux-4.19.y 3f8a27f9e27b 7f723fbe .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2021/10/09 08:10 linux-4.19.y 6db10b4d5efd efe0f24d .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2021/09/05 03:18 linux-4.19.y b172b44fcb17 d236a457 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2021/08/23 04:54 linux-4.19.y 59456c9cc40c b599f2fc .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2021/08/15 22:09 linux-4.19.y 59456c9cc40c 2489ab88 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
2021/08/15 18:20 linux-4.19.y 59456c9cc40c 2489ab88 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in tipc_udp_xmit
* Struck through repros no longer work on HEAD.