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KASAN: slab-use-after-free Read in sched_core_enqueue

Status: closed as invalid on 2024/09/13 10:29
Subsystems: net
[Documentation on labels]
First crash: 182d, last: 175d

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in __sched_core_less kernel/sched/core.c:234 [inline]
BUG: KASAN: slab-use-after-free in rb_sched_core_less kernel/sched/core.c:251 [inline]
BUG: KASAN: slab-use-after-free in rb_add include/linux/rbtree.h:203 [inline]
BUG: KASAN: slab-use-after-free in sched_core_enqueue+0x15b/0x580 kernel/sched/core.c:275
Read of size 8 at addr ffff88801f8c82d8 by task syz-executor/5840

CPU: 1 UID: 0 PID: 5840 Comm: syz-executor Not tainted 6.11.0-rc5-next-20240827-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 __sched_core_less kernel/sched/core.c:234 [inline]
 rb_sched_core_less kernel/sched/core.c:251 [inline]
 rb_add include/linux/rbtree.h:203 [inline]
 sched_core_enqueue+0x15b/0x580 kernel/sched/core.c:275
 activate_task+0x61/0xc0 kernel/sched/core.c:2056
 attach_task+0xee/0x190 kernel/sched/fair.c:9549
 attach_tasks kernel/sched/fair.c:9584 [inline]
 sched_balance_rq+0x65b1/0x8590 kernel/sched/fair.c:11661
 sched_balance_domains+0x565/0xa90 kernel/sched/fair.c:12069
 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline]
RIP: 0010:atomic_long_read include/linux/atomic/atomic-instrumented.h:3188 [inline]
RIP: 0010:__mutex_owner kernel/locking/mutex.c:81 [inline]
RIP: 0010:mutex_spin_on_owner+0x267/0x330 kernel/locking/mutex.c:359
Code: 48 8b 44 24 20 80 3c 18 00 74 08 4c 89 f7 e8 70 a9 8d 00 49 f7 06 01 00 00 00 0f 85 8b 00 00 00 f3 90 4c 89 f7 be 08 00 00 00 <e8> c4 ab 8d 00 48 8b 44 24 20 80 3c 18 00 0f 84 88 fe ff ff 4c 89
RSP: 0018:ffffc9001777f598 EFLAGS: 00000246
RAX: 1ffff1100581eb40 RBX: dffffc0000000000 RCX: ffffffff816f3c6c
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fcc6f20
RBP: ffff8880292a9e00 R08: ffffffff8fcc6f27 R09: 1ffffffff1f98de4
R10: dffffc0000000000 R11: fffffbfff1f98de5 R12: 0000000000000010
R13: ffffffff8fcc6fb0 R14: ffffffff8fcc6f20 R15: ffffffff8fcc6f70
 mutex_optimistic_spin kernel/locking/mutex.c:476 [inline]
 __mutex_lock_common kernel/locking/mutex.c:612 [inline]
 __mutex_lock+0x2cb/0xd70 kernel/locking/mutex.c:752
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643
 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 __sys_sendto+0x39b/0x4f0 net/socket.c:2204
 __do_sys_sendto net/socket.c:2216 [inline]
 __se_sys_sendto net/socket.c:2212 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2212
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc62397bd0c
Code: 2a 5a 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5a 02 00 48 8b
RSP: 002b:00007ffc84cfde40 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc624644620 RCX: 00007fc62397bd0c
RDX: 0000000000000028 RSI: 00007fc624644670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc84cfde94 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc624644670 R15: 0000000000000000
 </TASK>

Allocated by task 5992:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4040 [inline]
 slab_alloc_node mm/slub.c:4089 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4132
 alloc_task_struct_node kernel/fork.c:180 [inline]
 dup_task_struct+0x57/0x8c0 kernel/fork.c:1107
 copy_process+0x5d1/0x3d50 kernel/fork.c:2203
 kernel_clone+0x226/0x8f0 kernel/fork.c:2784
 __do_sys_clone3 kernel/fork.c:3088 [inline]
 __se_sys_clone3+0x2cb/0x350 kernel/fork.c:3067
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 24:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2299 [inline]
 slab_free mm/slub.c:4525 [inline]
 kmem_cache_free+0x194/0x3d0 mm/slub.c:4627
 put_task_struct include/linux/sched/task.h:139 [inline]
 delayed_put_task_struct+0x125/0x300 kernel/exit.c:228
 rcu_do_batch kernel/rcu/tree.c:2567 [inline]
 rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823
 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
 __call_rcu_common kernel/rcu/tree.c:3086 [inline]
 call_rcu+0x167/0xa70 kernel/rcu/tree.c:3190
 context_switch kernel/sched/core.c:5314 [inline]
 __schedule+0x1852/0x4b30 kernel/sched/core.c:6677
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6999
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

The buggy address belongs to the object at ffff88801f8c8000
 which belongs to the cache task_struct of size 7424
The buggy address is located 728 bytes inside of
 freed 7424-byte region [ffff88801f8c8000, ffff88801f8c9d00)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f8c8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88802b28f401
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff8880166f8500 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000040004 00000001f5000000 ffff88802b28f401
head: 00fff00000000040 ffff8880166f8500 0000000000000000 dead000000000001
head: 0000000000000000 0000000000040004 00000001f5000000 ffff88802b28f401
head: 00fff00000000003 ffffea00007e3201 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 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 5217, tgid 5217 (sshd), ts 62315991484, free_ts 62307120920
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1520
 prep_new_page mm/page_alloc.c:1528 [inline]
 get_page_from_freelist+0x312a/0x3270 mm/page_alloc.c:3479
 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2369
 allocate_slab+0x5a/0x2f0 mm/slub.c:2535
 new_slab mm/slub.c:2588 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3775
 __slab_alloc+0x58/0xa0 mm/slub.c:3865
 __slab_alloc_node mm/slub.c:3918 [inline]
 slab_alloc_node mm/slub.c:4077 [inline]
 kmem_cache_alloc_node_noprof+0x1fe/0x320 mm/slub.c:4132
 alloc_task_struct_node kernel/fork.c:180 [inline]
 dup_task_struct+0x57/0x8c0 kernel/fork.c:1107
 copy_process+0x5d1/0x3d50 kernel/fork.c:2203
 kernel_clone+0x226/0x8f0 kernel/fork.c:2784
 __do_sys_clone kernel/fork.c:2927 [inline]
 __se_sys_clone kernel/fork.c:2911 [inline]
 __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2911
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5217 tgid 5217 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1101 [inline]
 free_unref_page+0xc64/0xe80 mm/page_alloc.c:2654
 discard_slab mm/slub.c:2634 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3102
 put_cpu_partial+0x17c/0x250 mm/slub.c:3177
 __slab_free+0x2ea/0x3d0 mm/slub.c:4395
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4040 [inline]
 slab_alloc_node mm/slub.c:4089 [inline]
 __do_kmalloc_node mm/slub.c:4209 [inline]
 __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4222
 kmalloc_noprof include/linux/slab.h:685 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 security_inode_getattr+0x130/0x330 security/security.c:2371
 vfs_getattr+0x45/0x430 fs/stat.c:242
 vfs_fstat fs/stat.c:267 [inline]
 vfs_fstatat+0xe4/0x190 fs/stat.c:376
 __do_sys_newfstatat fs/stat.c:543 [inline]
 __se_sys_newfstatat fs/stat.c:537 [inline]
 __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:537
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88801f8c8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801f8c8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801f8c8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88801f8c8300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801f8c8380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
   5:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
   9:	74 08                	je     0x13
   b:	4c 89 f7             	mov    %r14,%rdi
   e:	e8 70 a9 8d 00       	call   0x8da983
  13:	49 f7 06 01 00 00 00 	testq  $0x1,(%r14)
  1a:	0f 85 8b 00 00 00    	jne    0xab
  20:	f3 90                	pause
  22:	4c 89 f7             	mov    %r14,%rdi
  25:	be 08 00 00 00       	mov    $0x8,%esi
* 2a:	e8 c4 ab 8d 00       	call   0x8dabf3 <-- trapping instruction
  2f:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
  34:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  38:	0f 84 88 fe ff ff    	je     0xfffffec6
  3e:	4c                   	rex.WR
  3f:	89                   	.byte 0x89

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/27 22:36 linux-next 6f923748057a 6c853ff9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in sched_core_enqueue
2024/08/21 17:43 linux-next eb8c5ca373cb db5852f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in sched_core_enqueue
2024/08/20 18:26 linux-next bb1b0acdcd66 9f0ab3fb .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in sched_core_enqueue
* Struck through repros no longer work on HEAD.