syzbot


KASAN: use-after-free Read in compute_effective_progs (2)

Status: upstream: reported C repro on 2022/04/03 08:00
Reported-by: syzbot+f264bffdfbd5614f3bb2@syzkaller.appspotmail.com
Fix commit: 3527e3cbb84d bpf: Fix KASAN use-after-free Read in compute_effective_progs
Patched on: [ci2-android-5-10 ci2-android-5-10-perf], missing on: []
First crash: 251d, last: 123d

Cause bisection: failed (bisect log)
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 KASAN: use-after-free Read in compute_effective_progs 1 393d 393d 0/2 closed as invalid on 2022/02/05 00:28
Patch testing requests:
Created Duration User Patch Repo Result
2022/06/02 16:28 16m tadeusz.struk@linaro.org https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master OK
2022/05/27 15:28 8m tadeusz.struk@linaro.org https://github.com/tstruk/linux.git master report log
2022/05/27 14:39 13m tadeusz.struk@linaro.org https://github.com/tstruk/linux.git master error
2022/05/26 22:36 9m tadeusz.struk@linaro.org https://github.com/tstruk/linux.git master error
2022/05/17 18:10 0m tadeusz.struk@linaro.org patch android12-5.10-lts error
2022/05/17 18:09 17m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK
2022/04/15 01:50 14m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK
2022/04/15 01:37 10m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK
2022/04/13 17:50 12m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK
2022/04/05 18:30 10m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK
2022/04/05 01:56 10m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK
2022/04/04 18:07 7m tadeusz.struk@linaro.org patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master report log
2022/04/04 17:55 8m tadeusz.struk@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master report log
2022/04/04 17:37 9m tadeusz.struk@linaro.org patch https://android.googlesource.com/kernel/common android12-5.10 report log

Sample crash report:
---[ end trace 71a8e909f523c1a2 ]---
==================================================================
BUG: KASAN: use-after-free in prog_list_prog kernel/bpf/cgroup.c:174 [inline]
BUG: KASAN: use-after-free in prog_list_length kernel/bpf/cgroup.c:187 [inline]
BUG: KASAN: use-after-free in compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240
Read of size 8 at addr ffff88811820e118 by task syz-executor320/373

CPU: 1 PID: 373 Comm: syz-executor320 Tainted: G        W         5.10.134-syzkaller-01772-gf6ce9a9115d5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x81/0x3c0 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 prog_list_prog kernel/bpf/cgroup.c:174 [inline]
 prog_list_length kernel/bpf/cgroup.c:187 [inline]
 compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240
 update_effective_progs+0x79/0x320 kernel/bpf/cgroup.c:343
 __cgroup_bpf_detach+0x312/0x570 kernel/bpf/cgroup.c:689
 bpf_cgroup_link_release+0x94/0x260 kernel/bpf/cgroup.c:833
 bpf_link_free kernel/bpf/syscall.c:2350 [inline]
 bpf_link_put+0x1e9/0x270 kernel/bpf/syscall.c:2376
 bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2384
 __fput+0x348/0x7c0 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 ptrace_notify+0x29a/0x340 kernel/signal.c:2279
 ptrace_report_syscall include/linux/tracehook.h:66 [inline]
 tracehook_report_syscall_exit include/linux/tracehook.h:129 [inline]
 arch_syscall_exit_tracehook include/linux/entry-common.h:284 [inline]
 syscall_exit_work+0x7c/0x130 kernel/entry/common.c:231
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:258 [inline]
 syscall_exit_to_user_mode+0x6a/0xa0 kernel/entry/common.c:264
 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x61/0xc6
RIP: 0033:0x7f88784ac2f3
Code: c7 c2 c0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8
RSP: 002b:00007ffd84b07208 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 00007f88784ac2f3
RDX: ffffffffffffffc0 RSI: 0000000000000007 RDI: 0000000000000008
RBP: 00007ffd84b07230 R08: 0000000000000001 R09: 00007ffd84b07240
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffd84b07250 R14: 00007ffd84b07290 R15: 0000000000000000

Allocated by task 373:
 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:428 [inline]
 ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:507
 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:516
 kasan_kmalloc include/linux/kasan.h:269 [inline]
 kmem_cache_alloc_trace+0x1dd/0x330 mm/slub.c:2983
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:664 [inline]
 cgroup_bpf_link_attach+0x12e/0x4a0 kernel/bpf/cgroup.c:918
 link_create+0x540/0x6e0 kernel/bpf/syscall.c:4092
 __do_sys_bpf+0x528/0x6c0 kernel/bpf/syscall.c:4497
 __se_sys_bpf kernel/bpf/syscall.c:4383 [inline]
 __x64_sys_bpf+0x7a/0x90 kernel/bpf/syscall.c:4383
 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xc6

Freed by task 373:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357
 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:360
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:368
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1604 [inline]
 slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1630
 slab_free mm/slub.c:3212 [inline]
 kfree+0xc3/0x290 mm/slub.c:4200
 bpf_cgroup_link_dealloc+0x15/0x20 kernel/bpf/cgroup.c:849
 bpf_link_free kernel/bpf/syscall.c:2354 [inline]
 bpf_link_put+0x243/0x270 kernel/bpf/syscall.c:2376
 bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2384
 __fput+0x348/0x7c0 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 ptrace_notify+0x29a/0x340 kernel/signal.c:2279
 ptrace_report_syscall include/linux/tracehook.h:66 [inline]
 tracehook_report_syscall_exit include/linux/tracehook.h:129 [inline]
 arch_syscall_exit_tracehook include/linux/entry-common.h:284 [inline]
 syscall_exit_work+0x7c/0x130 kernel/entry/common.c:231
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:258 [inline]
 syscall_exit_to_user_mode+0x6a/0xa0 kernel/entry/common.c:264
 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x61/0xc6

The buggy address belongs to the object at ffff88811820e100
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 96-byte region [ffff88811820e100, ffff88811820e160)
The buggy address belongs to the page:
page:ffffea0004608380 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11820e
flags: 0x8000000000000200(slab)
raw: 8000000000000200 dead000000000100 dead000000000122 ffff888100043680
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 361, ts 16642756972, free_ts 16614003897
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2385 [inline]
 prep_new_page mm/page_alloc.c:2391 [inline]
 get_page_from_freelist+0x745/0x760 mm/page_alloc.c:4067
 __alloc_pages_nodemask+0x3b6/0x890 mm/page_alloc.c:5117
 alloc_slab_page mm/slub.c:1815 [inline]
 allocate_slab+0x78/0x540 mm/slub.c:1817
 new_slab mm/slub.c:1878 [inline]
 new_slab_objects mm/slub.c:2636 [inline]
 ___slab_alloc+0x131/0x2e0 mm/slub.c:2800
 __slab_alloc+0x63/0xa0 mm/slub.c:2840
 slab_alloc_node mm/slub.c:2922 [inline]
 slab_alloc mm/slub.c:2964 [inline]
 kmem_cache_alloc_trace+0x20e/0x330 mm/slub.c:2981
 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline]
 kmalloc_node include/linux/slab.h:570 [inline]
 kzalloc_node include/linux/slab.h:675 [inline]
 __get_vm_area_node+0x134/0x200 mm/vmalloc.c:2077
 __vmalloc_node_range+0xd5/0x6d0 mm/vmalloc.c:2560
 __vmalloc_node mm/vmalloc.c:2608 [inline]
 __vmalloc+0x7a/0x90 mm/vmalloc.c:2622
 bpf_prog_alloc_no_stats+0x36/0x2d0 kernel/bpf/core.c:91
 bpf_prog_alloc+0x21/0x1f0 kernel/bpf/core.c:119
 bpf_prog_create_from_user+0xa0/0x400 net/core/filter.c:1413
 seccomp_prepare_filter kernel/seccomp.c:658 [inline]
 seccomp_prepare_user_filter kernel/seccomp.c:695 [inline]
 seccomp_set_mode_filter kernel/seccomp.c:1803 [inline]
 do_seccomp+0x8bd/0x13a0 kernel/seccomp.c:1923
 prctl_set_seccomp+0x4d/0x60 kernel/seccomp.c:1976
 __do_sys_prctl+0x8fb/0x12e0 kernel/sys.c:2515
 __se_sys_prctl kernel/sys.c:2433 [inline]
 __x64_sys_prctl+0xbf/0xd0 kernel/sys.c:2433
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1331 [inline]
 free_pcp_prepare+0x18c/0x1c0 mm/page_alloc.c:1405
 free_unref_page_prepare mm/page_alloc.c:3291 [inline]
 free_unref_page+0x6a/0x220 mm/page_alloc.c:3345
 __put_single_page mm/swap.c:102 [inline]
 __put_page+0xb1/0xd0 mm/swap.c:133
 put_page include/linux/mm.h:1253 [inline]
 anon_pipe_buf_release+0x18d/0x210 fs/pipe.c:137
 pipe_buf_release include/linux/pipe_fs_i.h:201 [inline]
 pipe_read+0x5c1/0x1070 fs/pipe.c:323
 call_read_iter include/linux/fs.h:1941 [inline]
 new_sync_read fs/read_write.c:415 [inline]
 vfs_read+0x9e2/0xbf0 fs/read_write.c:496
 ksys_read+0x198/0x2c0 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read fs/read_write.c:642 [inline]
 __x64_sys_read+0x7b/0x90 fs/read_write.c:642
 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xc6

Memory state around the buggy address:
 ffff88811820e000: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88811820e080: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88811820e100: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff88811820e180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88811820e200: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================

Crashes (11):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-android-5-10 2022/08/08 11:17 android12-5.10-lts f6ce9a9115d5 88e3a122 .config log report syz C KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/05/12 05:35 android12-5.10-lts de64d941a71a beb0b407 .config log report syz C KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/04/22 22:51 android12-5.10-lts e08dd85cc95e 131df97d .config log report syz C KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/04/03 07:53 android12-5.10-lts 414e6c8e941c 79a2a8fc .config log report syz C KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/08/06 21:07 android12-5.10-lts f6ce9a9115d5 88e3a122 .config log report info KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/07/12 00:52 android12-5.10-lts fa7f6a5f56d9 da3d6955 .config log report info KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/07/07 12:55 android12-5.10-lts fa7f6a5f56d9 bff65f44 .config log report info KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/06/14 01:40 android12-5.10-lts fdd06dc6b0f8 0f087040 .config log report info KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/05/14 20:05 android12-5.10-lts 2ed28105c6c4 744a39e2 .config log report info KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/05/02 17:13 android12-5.10-lts de64d941a71a 2df221f6 .config log report info KASAN: use-after-free Read in compute_effective_progs
ci2-android-5-10 2022/04/03 07:36 android12-5.10-lts 414e6c8e941c 79a2a8fc .config log report info KASAN: use-after-free Read in compute_effective_progs
* Struck through repros no longer work on HEAD.