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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: 187d, last: 2d08h
▶ ▼ Similar bugs (12)
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 545d 545d 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 1085d 1160d 0/1 auto-closed as invalid on 2021/09/06 04:07
linux-6.1 KASAN: use-after-free Read in tcp_retransmit_timer 14 28d 47d 0/3 upstream: reported on 2024/03/12 12:56
linux-4.19 KASAN: use-after-free Read in tcp_retransmit_timer 2 1584d 1585d 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 1868d 1868d 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 513d 1525d 22/26 fixed on 2023/02/24 13:50
linux-4.19 KASAN: use-after-free Read in tcp_retransmit_timer (2) 6 1014d 1181d 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 1780d 1800d 0/26 closed as invalid on 2019/07/01 18:06
upstream KASAN: use-after-free Read in tcp_retransmit_timer net 4 1911d 2025d 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 692d 871d 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 1725d 1725d 0/26 closed as invalid on 2019/10/03 04:18
linux-5.15 KASAN: use-after-free Read in tcp_retransmit_timer 76 297d 404d 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 ffff8880796fb6d8 by task swapper/1/0

CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <IRQ>
 __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
 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:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 __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:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570
Code: 4d 59 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 84 c9 5f f7 0f 1f 44 00 00 e8 7a 49 59 f7 0f 00 2d f3 06 bc 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 9b 0e a3 f7
RSP: 0018:ffffc90000d67b00 EFLAGS: 000002d3
RAX: ffffffff8a271366 RBX: 0000000000000000 RCX: ffff888012a00000
RDX: 0000000000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f380
RBP: ffffc90000d67b90 R08: ffffffff8186dd10 R09: ffffed1002540001
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001acf60
R13: ffff888018dd2804 R14: ffffc90000d67b20 R15: dffffc0000000000
 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:705
 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x3e4/0x670 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>

Allocated by task 6351:
 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+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 3999:
 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:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300

The buggy address belongs to the object at ffff8880796fb480
 which belongs to the cache net_namespace of size 6464
The buggy address is located 600 bytes inside of
 6464-byte region [ffff8880796fb480, ffff8880796fcdc0)
The buggy address belongs to the page:
page:ffffea0001e5be00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x796f8
head:ffffea0001e5be00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888074d3efc1
flags: 0xfff80000010200(slab|head|node=0|zone=1|lastcpupid=0xfff)
raw: 00fff80000010200 ffffea0001dd3c00 0000000200000002 ffff888011dec3c0
raw: 0000000000000000 0000000080040004 00000001ffffffff ffff888074d3efc1
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 3517, ts 50314635433, free_ts 49758152258
 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+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+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
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
 put_page include/linux/mm.h:1247 [inline]
 __skb_frag_unref include/linux/skbuff.h:3219 [inline]
 skb_release_data+0x411/0x8a0 net/core/skbuff.c:672
 skb_release_all net/core/skbuff.c:742 [inline]
 __kfree_skb+0x4c/0x60 net/core/skbuff.c:756
 sk_eat_skb include/net/sock.h:2723 [inline]
 tcp_recvmsg_locked+0x1629/0x29b0 net/ipv4/tcp.c:2516
 tcp_recvmsg+0x24e/0x7f0 net/ipv4/tcp.c:2562
 inet_recvmsg+0x157/0x280 net/ipv4/af_inet.c:859
 sock_recvmsg_nosec net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:984 [inline]
 sock_read_iter+0x353/0x480 net/socket.c:1057
 call_read_iter include/linux/fs.h:2166 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0xa9f/0xe10 fs/read_write.c:485
 ksys_read+0x1a2/0x2c0 fs/read_write.c:623
 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

Memory state around the buggy address:
 ffff8880796fb580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880796fb600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880796fb680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff8880796fb700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880796fb780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	4d 59                	rex.WRB pop %r9
   2:	f7 48 83 e3 08 0f 85 	testl  $0x850f08e3,-0x7d(%rax)
   9:	0a 01                	or     (%rcx),%al
   b:	00 00                	add    %al,(%rax)
   d:	4c 8d 74 24 20       	lea    0x20(%rsp),%r14
  12:	e8 84 c9 5f f7       	call   0xf75fc99b
  17:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  1c:	e8 7a 49 59 f7       	call   0xf759499b
  21:	0f 00 2d f3 06 bc 00 	verw   0xbc06f3(%rip)        # 0xbc071b
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	4c 89 f3             	mov    %r14,%rbx <-- trapping instruction
  2d:	48 c1 eb 03          	shr    $0x3,%rbx
  31:	42 80 3c 3b 00       	cmpb   $0x0,(%rbx,%r15,1)
  36:	74 08                	je     0x40
  38:	4c 89 f7             	mov    %r14,%rdi
  3b:	e8 9b 0e a3 f7       	call   0xf7a30edb

Crashes (13):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/26 05:25 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/03/20 03:44 linux-5.15.y b95c01af2113 a485f239 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/03/19 13:09 linux-5.15.y b95c01af2113 e104824c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/03/18 14:26 linux-5.15.y b95c01af2113 baa80228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/03/17 05:24 linux-5.15.y b95c01af2113 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/03/15 21:32 linux-5.15.y b95c01af2113 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tcp_retransmit_timer
2024/02/26 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
2024/03/13 10:37 linux-5.15.y 574362648507 db5b7ff0 .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
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.