syzbot


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

Status: upstream: reported C repro on 2024/08/21 01:31
Subsystems: perf
[Documentation on labels]
Reported-by: syzbot+b32fa80fe75273685f9c@syzkaller.appspotmail.com
First crash: 26d, last: 24d
Cause bisection: introduced by (bisect log) [release commit]:
commit c9c3395d5e3dcc6daee66c6908354d47bf98cb0c
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sun Feb 19 22:24:22 2023 +0000

  Linux 6.2

Crash: lost connection to test machine (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [perf?] KASAN: slab-use-after-free Read in uprobe_unregister 1 (3) 2024/08/21 05:11

Sample crash report:
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
==================================================================
BUG: KASAN: slab-use-after-free in consumer_del kernel/events/uprobes.c:772 [inline]
BUG: KASAN: slab-use-after-free in uprobe_unregister+0x99/0x220 kernel/events/uprobes.c:1097
Read of size 8 at addr ffff888022b9eb40 by task syz-executor227/5226

CPU: 0 UID: 0 PID: 5226 Comm: syz-executor227 Not tainted 6.11.0-rc3-next-20240816-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __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
 consumer_del kernel/events/uprobes.c:772 [inline]
 uprobe_unregister+0x99/0x220 kernel/events/uprobes.c:1097
 bpf_uprobe_unregister kernel/trace/bpf_trace.c:3119 [inline]
 bpf_uprobe_multi_link_release+0x8c/0x1b0 kernel/trace/bpf_trace.c:3127
 bpf_link_free+0xf5/0x250 kernel/bpf/syscall.c:2998
 bpf_link_put_direct kernel/bpf/syscall.c:3038 [inline]
 bpf_link_release+0x7b/0x90 kernel/bpf/syscall.c:3045
 __fput+0x24b/0x890 fs/file_table.c:424
 task_work_run+0x24f/0x310 kernel/task_work.c:228
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:939
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 __do_sys_exit_group kernel/exit.c:1099 [inline]
 __se_sys_exit_group kernel/exit.c:1097 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 0033:0x7f409a857c79
Code: Unable to access opcode bytes at 0x7f409a857c4f.
RSP: 002b:00007fff689d0b48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f409a857c79
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007f409a8cb370 R08: ffffffffffffffb8 R09: 00000000000000a0
R10: 0000000000000001 R11: 0000000000000246 R12: 00007f409a8cb370
R13: 0000000000000000 R14: 00007f409a8cbdc0 R15: 00007f409a821340
 </TASK>

Allocated by task 5226:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4202 [inline]
 __kmalloc_node_noprof+0x22a/0x440 mm/slub.c:4208
 __kvmalloc_node_noprof+0x72/0x1b0 mm/util.c:658
 kvmalloc_array_node_noprof include/linux/slab.h:835 [inline]
 bpf_uprobe_multi_link_attach+0x43e/0xb90 kernel/trace/bpf_trace.c:3369
 link_create+0x6e9/0x870 kernel/bpf/syscall.c:5236
 __sys_bpf+0x4bc/0x810 kernel/bpf/syscall.c:5697
 __do_sys_bpf kernel/bpf/syscall.c:5734 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5732 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5732
 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 5226:
 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:2295 [inline]
 slab_free mm/slub.c:4517 [inline]
 kfree+0x196/0x3e0 mm/slub.c:4665
 bpf_uprobe_multi_link_attach+0xa7d/0xb90 kernel/trace/bpf_trace.c:3431
 link_create+0x6e9/0x870 kernel/bpf/syscall.c:5236
 __sys_bpf+0x4bc/0x810 kernel/bpf/syscall.c:5697
 __do_sys_bpf kernel/bpf/syscall.c:5734 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5732 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5732
 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

The buggy address belongs to the object at ffff888022b9eb00
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 64 bytes inside of
 freed 96-byte region [ffff888022b9eb00, ffff888022b9eb60)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888022b9e400 pfn:0x22b9e
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000000 ffff888015841280 ffffea000061ec40 dead000000000004
raw: ffff888022b9e400 000000008020001f 00000001fdffffff 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 0x52c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4681, tgid 4681 (udevd), ts 17930004975, free_ts 17928166567
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1518
 prep_new_page mm/page_alloc.c:1526 [inline]
 get_page_from_freelist+0x3004/0x30c0 mm/page_alloc.c:3477
 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4744
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2364
 allocate_slab+0x5a/0x2f0 mm/slub.c:2527
 new_slab mm/slub.c:2580 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3767
 __slab_alloc+0x58/0xa0 mm/slub.c:3857
 __slab_alloc_node mm/slub.c:3910 [inline]
 slab_alloc_node mm/slub.c:4069 [inline]
 __do_kmalloc_node mm/slub.c:4201 [inline]
 __kmalloc_noprof+0x25a/0x400 mm/slub.c:4214
 kmalloc_noprof include/linux/slab.h:685 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x255/0x500 security/tomoyo/file.c:771
 security_file_open+0x6a/0x750 security/security.c:2996
 do_dentry_open+0x359/0x13f0 fs/open.c:946
 vfs_open+0x3e/0x330 fs/open.c:1089
 do_open fs/namei.c:3774 [inline]
 path_openat+0x2c87/0x3590 fs/namei.c:3933
 do_filp_open+0x235/0x490 fs/namei.c:3960
page last free pid 4688 tgid 4688 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1099 [inline]
 free_unref_page+0xc07/0xd90 mm/page_alloc.c:2652
 __slab_free+0x31b/0x3d0 mm/slub.c:4428
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9e/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:4032 [inline]
 slab_alloc_node mm/slub.c:4081 [inline]
 __kmalloc_cache_noprof+0x132/0x2c0 mm/slub.c:4228
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 kernfs_fop_open+0x3e0/0xd10 fs/kernfs/file.c:623
 do_dentry_open+0x928/0x13f0 fs/open.c:959
 vfs_open+0x3e/0x330 fs/open.c:1089
 do_open fs/namei.c:3774 [inline]
 path_openat+0x2c87/0x3590 fs/namei.c:3933
 do_filp_open+0x235/0x490 fs/namei.c:3960
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1442
 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:
 ffff888022b9ea00: 00 00 00 00 00 00 00 00 00 00 00 06 fc fc fc fc
 ffff888022b9ea80: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
>ffff888022b9eb00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                                           ^
 ffff888022b9eb80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff888022b9ec00: 00 00 00 00 00 00 00 00 00 00 00 06 fc fc fc fc
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/17 08:36 linux-next 367b5c3d53e5 76120936 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in uprobe_unregister
2024/08/17 04:21 linux-next 367b5c3d53e5 76120936 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in uprobe_unregister
2024/08/17 03:44 linux-next 367b5c3d53e5 76120936 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in uprobe_unregister
2024/08/19 09:34 linux-next 367b5c3d53e5 dbc93b08 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in uprobe_unregister
2024/08/17 01:19 linux-next 367b5c3d53e5 76120936 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in uprobe_unregister
* Struck through repros no longer work on HEAD.