syzbot


KASAN: use-after-free Read in dump_schedule

Status: upstream: reported C repro on 2024/03/23 08:43
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+7cf7333eb728a0d62e89@syzkaller.appspotmail.com
First crash: 88d, last: 54d
Fix bisection: failed (error log, bisect log)
  
Bug presence (1)
Date Name Commit Repro Result
2024/04/27 upstream (ToT) 5eb4573ea63d C [report] KASAN: slab-use-after-free Read in taprio_dump
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in dump_schedule net C done done 7 1274d 1385d 19/27 fixed on 2021/03/10 01:48
linux-6.1 KASAN: use-after-free Read in dump_schedule origin:upstream syz error 2 66d 86d 0/3 upstream: reported syz repro on 2024/03/25 15:23
upstream KASAN: use-after-free Read in dump_schedule (2) net C done inconclusive 10 562d 1122d 0/27 auto-obsoleted due to no activity on 2023/10/12 02:40
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2024/05/30 17:15 0m bisect fix linux-5.15.y error job log (0)
2024/04/26 03:37 1h38m bisect fix linux-5.15.y job log (0) log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in dump_schedule+0xbd/0x940 net/sched/sch_taprio.c:1863
Read of size 8 at addr ffff88806fea5740 by task syz-executor208/4865

CPU: 1 PID: 4865 Comm: syz-executor208 Not tainted 5.15.152-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <TASK>
 __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
 dump_schedule+0xbd/0x940 net/sched/sch_taprio.c:1863
 taprio_dump+0xa85/0xeb0 net/sched/sch_taprio.c:1931
 tc_fill_qdisc+0x698/0x11d0 net/sched/sch_api.c:923
 qdisc_notify+0x1e4/0x380 net/sched/sch_api.c:990
 tc_modify_qdisc+0x1573/0x1760 net/sched/sch_api.c:1688
 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
 netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
 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_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 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
RIP: 0033:0x7fc1c58eaae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdc7ef1e48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc1c58eaae9
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004
RBP: 00000000000f4240 R08: 0000000100000000 R09: 0000000100000000
R10: 0000000100000000 R11: 0000000000000246 R12: 00007ffdc7ef1ea0
R13: 000000000000f181 R14: 00007ffdc7ef1e6c R15: 0000000000000003
 </TASK>

Allocated by task 4856:
 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]
 kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 taprio_change+0x427/0x5200 net/sched/sch_taprio.c:1498
 qdisc_change+0x274/0x600 net/sched/sch_api.c:1349
 tc_modify_qdisc+0x151f/0x1760 net/sched/sch_api.c:1686
 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
 netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
 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_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 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 0:
 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
 rcu_do_batch kernel/rcu/tree.c:2523 [inline]
 rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558

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
 __call_rcu kernel/rcu/tree.c:3007 [inline]
 call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3087
 taprio_change+0x407a/0x5200 net/sched/sch_taprio.c:1618
 qdisc_change+0x274/0x600 net/sched/sch_api.c:1349
 tc_modify_qdisc+0x151f/0x1760 net/sched/sch_api.c:1686
 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
 netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
 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_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 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 ffff88806fea5700
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 64 bytes inside of
 96-byte region [ffff88806fea5700, ffff88806fea5760)
The buggy address belongs to the page:
page:ffffea0001bfa940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6fea5
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888011c41780
raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 4817, ts 61626287705, free_ts 61590193055
 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_trace+0x1a0/0x290 mm/slub.c:3245
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 taprio_change+0x427/0x5200 net/sched/sch_taprio.c:1498
 qdisc_change+0x274/0x600 net/sched/sch_api.c:1349
 tc_modify_qdisc+0x151f/0x1760 net/sched/sch_api.c:1686
 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
 netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
 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_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/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_list+0x1f7/0x8e0 mm/page_alloc.c:3433
 release_pages+0x1bb9/0x1f40 mm/swap.c:963
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:338
 exit_mmap+0x3cd/0x670 mm/mmap.c:3188
 __mmput+0x112/0x3b0 kernel/fork.c:1126
 exit_mm+0x688/0x7f0 kernel/exit.c:548
 do_exit+0x626/0x2480 kernel/exit.c:859
 do_group_exit+0x144/0x310 kernel/exit.c:994
 __do_sys_exit_group kernel/exit.c:1005 [inline]
 __se_sys_exit_group kernel/exit.c:1003 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1003
 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:
 ffff88806fea5600: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88806fea5680: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88806fea5700: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                                           ^
 ffff88806fea5780: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88806fea5800: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/26 10:12 linux-5.15.y b95c01af2113 bcd9b39f .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in dump_schedule
2024/03/23 08:43 linux-5.15.y b95c01af2113 0ea90952 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in dump_schedule
* Struck through repros no longer work on HEAD.