[syzbot] [kernel?] KASAN: slab-use-after-free Read in kill_orphaned_pgrp (2)

From: syzbot
Date: Wed May 08 2024 - 14:04:39 EST

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Hello,

syzbot found the following issue on:

HEAD commit: dccb07f2914c Merge tag 'for-6.9-rc7-tag' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12928970980000
kernel config: https://syzkaller.appspot.com/x/.config?x=6d14c12b661fb43
dashboard link: https://syzkaller.appspot.com/bug?extid=68619f9e9e69accd8e0a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bc129693f2cc/disk-dccb07f2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cf12611cfdc7/vmlinux-dccb07f2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/311fbc1afd69/bzImage-dccb07f2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+68619f9e9e69accd8e0a@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: slab-use-after-free in task_pgrp include/linux/sched/signal.h:689 [inline]
BUG: KASAN: slab-use-after-free in kill_orphaned_pgrp+0x41/0x560 kernel/exit.c:379
Read of size 8 at addr ffff888064362708 by task vhost-9668/9669

CPU: 0 PID: 9669 Comm: vhost-9668 Not tainted 6.9.0-rc7-syzkaller-00012-gdccb07f2914c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
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
task_pgrp include/linux/sched/signal.h:689 [inline]
kill_orphaned_pgrp+0x41/0x560 kernel/exit.c:379
exit_notify kernel/exit.c:739 [inline]
do_exit+0x1673/0x27e0 kernel/exit.c:898
vhost_task_fn+0x2ff/0x320 kernel/vhost_task.c:61
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

Allocated by task 8534:
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:312 [inline]
__kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook mm/slub.c:3804 [inline]
slab_alloc_node mm/slub.c:3851 [inline]
kmem_cache_alloc_node+0x194/0x390 mm/slub.c:3894
alloc_task_struct_node kernel/fork.c:176 [inline]
dup_task_struct+0x57/0x7d0 kernel/fork.c:1107
copy_process+0x5d1/0x3df0 kernel/fork.c:2220
kernel_clone+0x226/0x8f0 kernel/fork.c:2797
__do_sys_clone kernel/fork.c:2940 [inline]
__se_sys_clone kernel/fork.c:2924 [inline]
__x64_sys_clone+0x258/0x2a0 kernel/fork.c:2924
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5326:
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+0xa6/0xe0 mm/kasan/common.c:240
__kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2111 [inline]
slab_free mm/slub.c:4286 [inline]
kmem_cache_free+0x10b/0x2d0 mm/slub.c:4350
put_task_struct include/linux/sched/task.h:138 [inline]
delayed_put_task_struct+0x125/0x2f0 kernel/exit.c:229
rcu_do_batch kernel/rcu/tree.c:2196 [inline]
rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471
handle_softirqs+0x2d6/0x990 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:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

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:2734 [inline]
call_rcu+0x167/0xa70 kernel/rcu/tree.c:2838
release_task+0x16d2/0x1810
de_thread fs/exec.c:1172 [inline]
begin_new_exec+0xfde/0x1ce0 fs/exec.c:1278
load_elf_binary+0xb12/0x2e40 fs/binfmt_elf.c:996
search_binary_handler fs/exec.c:1778 [inline]
exec_binprm fs/exec.c:1820 [inline]
bprm_execve+0xaf8/0x17c0 fs/exec.c:1872
do_execveat_common+0x553/0x700 fs/exec.c:1979
do_execve fs/exec.c:2053 [inline]
__do_sys_execve fs/exec.c:2129 [inline]
__se_sys_execve fs/exec.c:2124 [inline]
__x64_sys_execve+0x92/0xb0 fs/exec.c:2124
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888064361e00
which belongs to the cache task_struct of size 7424
The buggy address is located 2312 bytes inside of
freed 7424-byte region [ffff888064361e00, ffff888064363b00)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x64360
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88801ed27d81
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888015eea500 ffffea00008c9e00 dead000000000002
raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88801ed27d81
head: 00fff00000000840 ffff888015eea500 ffffea00008c9e00 dead000000000002
head: 0000000000000000 0000000000040004 00000001ffffffff ffff88801ed27d81
head: 00fff00000000003 ffffea000190d801 dead000000000122 00000000ffffffff
head: 0000000800000000 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 4538, tgid -361552985 (udevd), ts 4538, free_ts 24654065279
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
prep_new_page mm/page_alloc.c:1541 [inline]
get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
__alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page+0x5f/0x160 mm/slub.c:2180
allocate_slab mm/slub.c:2343 [inline]
new_slab+0x84/0x2f0 mm/slub.c:2396
___slab_alloc+0xc73/0x1260 mm/slub.c:3530
__slab_alloc mm/slub.c:3615 [inline]
__slab_alloc_node mm/slub.c:3668 [inline]
slab_alloc_node mm/slub.c:3841 [inline]
kmem_cache_alloc_node+0x24a/0x390 mm/slub.c:3894
alloc_task_struct_node kernel/fork.c:176 [inline]
dup_task_struct+0x57/0x7d0 kernel/fork.c:1107
copy_process+0x5d1/0x3df0 kernel/fork.c:2220
kernel_clone+0x226/0x8f0 kernel/fork.c:2797
__do_sys_clone kernel/fork.c:2940 [inline]
__se_sys_clone kernel/fork.c:2924 [inline]
__x64_sys_clone+0x258/0x2a0 kernel/fork.c:2924
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 1 tgid 1 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1141 [inline]
free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347
free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
free_contig_range+0x9e/0x160 mm/page_alloc.c:6572
destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1036
debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1416
do_one_initcall+0x248/0x880 init/main.c:1245
do_initcall_level+0x157/0x210 init/main.c:1307
do_initcalls+0x3f/0x80 init/main.c:1323
kernel_init_freeable+0x435/0x5d0 init/main.c:1555
kernel_init+0x1d/0x2b0 init/main.c:1444
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
ffff888064362600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888064362680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888064362700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888064362780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888064362800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

---
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Next message: David Hildenbrand: "Re: [PATCH v2 10/10] s390/hugetlb: convert PG_arch_1 code to work on folio->flags"
Previous message: Chang S. Bae: "Re: [PATCH v2 1/2] x86/fpu: Extend kernel_fpu_begin_mask() to initialize AMX state"
Next in thread: lee bruce: "Re: [syzbot] [kernel?] KASAN: slab-use-after-free Read in kill_orphaned_pgrp (2)"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]