syzbot


KASAN: use-after-free Read in __io_req_task_work_add

Status: auto-obsoleted due to no activity on 2023/03/17 09:30
Subsystems: io-uring
[Documentation on labels]
Reported-by: syzbot+01db4d8aed628ede44b1@syzkaller.appspotmail.com
First crash: 456d, last: 452d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] KASAN: use-after-free Read in __io_req_task_work_add 2 (5) 2023/01/12 17:43

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __io_req_task_work_add+0x6b4/0x760 io_uring/io_uring.c:1287
Read of size 8 at addr ffff88802677e018 by task syz-executor.3/10166

CPU: 1 PID: 10166 Comm: syz-executor.3 Not tainted 6.2.0-rc3-next-20230112-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:306 [inline]
 print_report+0x15e/0x45d mm/kasan/report.c:417
 kasan_report+0xc0/0xf0 mm/kasan/report.c:517
 __io_req_task_work_add+0x6b4/0x760 io_uring/io_uring.c:1287
 io_req_task_work_add io_uring/io_uring.h:95 [inline]
 __io_poll_execute io_uring/poll.c:366 [inline]
 io_poll_execute.constprop.0+0x15b/0x190 io_uring/poll.c:372
 io_poll_cancel_req io_uring/poll.c:379 [inline]
 io_poll_remove_all_table+0x26d/0x2bd io_uring/poll.c:741
 io_poll_remove_all+0x2e/0x4b io_uring/poll.c:759
 io_ring_ctx_wait_and_kill+0x1a0/0x340 io_uring/io_uring.c:3017
 io_uring_release+0x46/0x4a io_uring/io_uring.c:3042
 __fput+0x27c/0xa90 fs/file_table.c:321
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xb17/0x2a90 kernel/exit.c:867
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012
 __do_sys_exit_group kernel/exit.c:1023 [inline]
 __se_sys_exit_group kernel/exit.c:1021 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1021
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb1e428c0c9
Code: Unable to access opcode bytes at 0x7fb1e428c09f.
RSP: 002b:00007ffdf8be85d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007fb1e428c0c9
RDX: 00007fb1e423df7b RSI: ffffffffffffffb8 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000062835e5b R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffdf8be86c0
 </TASK>

Allocated by task 10166:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:325
 kasan_slab_alloc include/linux/kasan.h:186 [inline]
 slab_post_alloc_hook mm/slab.h:769 [inline]
 slab_alloc_node mm/slub.c:3452 [inline]
 kmem_cache_alloc_node+0x183/0x350 mm/slub.c:3497
 alloc_task_struct_node kernel/fork.c:171 [inline]
 dup_task_struct kernel/fork.c:979 [inline]
 copy_process+0x3aa/0x7740 kernel/fork.c:2103
 kernel_clone+0xeb/0x9a0 kernel/fork.c:2687
 __do_sys_clone+0xba/0x100 kernel/fork.c:2828
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 21:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:518
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:162 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807
 slab_free mm/slub.c:3787 [inline]
 kmem_cache_free+0xec/0x4e0 mm/slub.c:3809
 put_task_struct include/linux/sched/task.h:119 [inline]
 delayed_put_task_struct+0x26e/0x3f0 kernel/exit.c:225
 rcu_do_batch kernel/rcu/tree.c:2113 [inline]
 rcu_core+0x821/0x1920 kernel/rcu/tree.c:2373
 __do_softirq+0x1fb/0xaf6 kernel/softirq.c:571

Last potentially related work creation:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488
 __call_rcu_common.constprop.0+0x99/0x780 kernel/rcu/tree.c:2622
 put_task_struct_rcu_user+0x83/0xc0 kernel/exit.c:231
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x25d8/0x5a70 kernel/sched/core.c:6619
 schedule+0xde/0x1b0 kernel/sched/core.c:6695
 futex_wait_queue+0xf9/0x1f0 kernel/futex/waitwake.c:355
 futex_wait+0x292/0x680 kernel/futex/waitwake.c:656
 do_futex+0x2e8/0x360 kernel/futex/syscalls.c:106
 __do_sys_futex kernel/futex/syscalls.c:183 [inline]
 __se_sys_futex kernel/futex/syscalls.c:164 [inline]
 __x64_sys_futex+0x1ca/0x4d0 kernel/futex/syscalls.c:164
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Second to last potentially related work creation:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488
 __call_rcu_common.constprop.0+0x99/0x780 kernel/rcu/tree.c:2622
 put_task_struct_rcu_user+0x83/0xc0 kernel/exit.c:231
 release_task+0xcc8/0x1870 kernel/exit.c:281
 wait_task_zombie kernel/exit.c:1198 [inline]
 wait_consider_task+0x306d/0x3ce0 kernel/exit.c:1425
 do_wait_thread kernel/exit.c:1488 [inline]
 do_wait+0x7cd/0xd90 kernel/exit.c:1605
 kernel_wait4+0x150/0x260 kernel/exit.c:1768
 __do_sys_wait4+0x13f/0x150 kernel/exit.c:1796
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88802677d7c0
 which belongs to the cache task_struct of size 7232
The buggy address is located 2136 bytes inside of
 7232-byte region [ffff88802677d7c0, ffff88802677f400)

The buggy address belongs to the physical page:
page:ffffea000099de00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26778
head:ffffea000099de00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88802041f081
anon flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff8880125ec500 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88802041f081
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 8511, tgid 8511 (syz-executor.1), ts 504921457471, free_ts 504913568116
 prep_new_page mm/page_alloc.c:2549 [inline]
 get_page_from_freelist+0x11bb/0x2d50 mm/page_alloc.c:4324
 __alloc_pages+0x1cb/0x5c0 mm/page_alloc.c:5590
 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2281
 alloc_slab_page mm/slub.c:1851 [inline]
 allocate_slab+0x25f/0x350 mm/slub.c:1998
 new_slab mm/slub.c:2051 [inline]
 ___slab_alloc+0xa91/0x1400 mm/slub.c:3193
 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292
 __slab_alloc_node mm/slub.c:3345 [inline]
 slab_alloc_node mm/slub.c:3442 [inline]
 kmem_cache_alloc_node+0x136/0x350 mm/slub.c:3497
 alloc_task_struct_node kernel/fork.c:171 [inline]
 dup_task_struct kernel/fork.c:979 [inline]
 copy_process+0x3aa/0x7740 kernel/fork.c:2103
 kernel_clone+0xeb/0x9a0 kernel/fork.c:2687
 __do_sys_clone+0xba/0x100 kernel/fork.c:2828
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1451 [inline]
 free_pcp_prepare+0x4d0/0x910 mm/page_alloc.c:1501
 free_unref_page_prepare mm/page_alloc.c:3387 [inline]
 free_unref_page+0x1d/0x490 mm/page_alloc.c:3482
 __folio_put_large mm/swap.c:119 [inline]
 __folio_put+0x109/0x140 mm/swap.c:127
 folio_put include/linux/mm.h:1203 [inline]
 put_page include/linux/mm.h:1272 [inline]
 __skb_frag_unref include/linux/skbuff.h:3388 [inline]
 skb_release_data+0x522/0x870 net/core/skbuff.c:843
 skb_release_all net/core/skbuff.c:914 [inline]
 __kfree_skb+0x4f/0x70 net/core/skbuff.c:928
 tcp_wmem_free_skb include/net/tcp.h:302 [inline]
 tcp_rtx_queue_unlink_and_free include/net/tcp.h:1938 [inline]
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3334 [inline]
 tcp_ack+0x1e0a/0x5a10 net/ipv4/tcp_input.c:3884
 tcp_rcv_established+0x667/0x2270 net/ipv4/tcp_input.c:6006
 tcp_v4_do_rcv+0x663/0x9d0 net/ipv4/tcp_ipv4.c:1721
 tcp_v4_rcv+0x2eab/0x3280 net/ipv4/tcp_ipv4.c:2142
 ip_protocol_deliver_rcu+0x9f/0x480 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2ec/0x4f0 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:302 [inline]
 NF_HOOK include/linux/netfilter.h:296 [inline]
 ip_local_deliver+0x1ae/0x200 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:454 [inline]
 ip_sublist_rcv_finish+0x9a/0x2c0 net/ipv4/ip_input.c:580
 ip_list_rcv_finish.constprop.0+0x4f9/0x6c0 net/ipv4/ip_input.c:630
 ip_sublist_rcv net/ipv4/ip_input.c:638 [inline]
 ip_list_rcv+0x347/0x4a0 net/ipv4/ip_input.c:673
 __netif_receive_skb_list_ptype net/core/dev.c:5525 [inline]
 __netif_receive_skb_list_core+0x548/0x8f0 net/core/dev.c:5573

Memory state around the buggy address:
 ffff88802677df00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802677df80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802677e000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88802677e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802677e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/16 09:30 linux-next 0a093b2893c7 a63719e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
2023/01/16 04:17 linux-next 0a093b2893c7 a63719e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
2023/01/15 12:05 linux-next 0a093b2893c7 a63719e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
2023/01/15 02:34 linux-next 0a093b2893c7 a63719e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
2023/01/12 12:46 linux-next 0a093b2893c7 96166539 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
2023/01/12 11:10 linux-next 0a093b2893c7 96166539 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
2023/01/12 09:27 linux-next 0a093b2893c7 96166539 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in __io_req_task_work_add
* Struck through repros no longer work on HEAD.