ci2-android-5-10/strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ci2-android-5-10/syz-executor207020630 <...> Warning: Permanently added '10.128.1.105' (ED25519) to the list of known hosts. execve("ci2-android-5-10/syz-executor207020630", ["ci2-android-5-10/syz-executor207020630"], 0x7fff55cb1a50 /* 10 vars */) = 0 brk(NULL) = 0x55556e521000 brk(0x55556e521d40) = 0x55556e521d40 arch_prctl(ARCH_SET_FS, 0x55556e5213c0) = 0 set_tid_address(0x55556e521690) = 297 set_robust_list(0x55556e5216a0, 24) = 0 rseq({cpu_id_start=0, cpu_id=RSEQ_CPU_ID_UNINITIALIZED, rseq_cs=NULL, flags=0, node_id=0, mm_cid=0, slice_ctrl={request=0, granted=0, __reserved=0}, __reserved=0}, 32, 0, 0x53053053) = -1 ENOSYS (Function not implemented) prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0 readlinkat(AT_FDCWD, "/proc/self/exe", "/root/ci2-android-5-10/syz-executor207020630", 4096) = 44 getrandom("\xf0\xc4\x35\xd7\xe0\x81\xb4\xe8", 8, GRND_NONBLOCK) = 8 brk(NULL) = 0x55556e521d40 brk(0x55556e542d40) = 0x55556e542d40 brk(0x55556e543000) = 0x55556e543000 mprotect(0x7fcd0587a000, 20480, PROT_READ) = 0 mmap(0x1ffffffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x1ffffffff000 mmap(0x200000000000, 16777216, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x200000000000 mmap(0x200001000000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x200001000000 executing program write(1, "executing program\n", 18) = 18 socket(AF_PPPOX, SOCK_STREAM, 1) = 3 socket(AF_INET6, SOCK_DGRAM, IPPROTO_IP) = 4 connect(3, {sa_family=AF_PPPOX, sa_data="\x01\x00\x00\x00\x03\x00\x00\x00\x04\x00\x00\x00\x02\x00\x4e\x23\xff\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x04\x00\x40\x00\x00\x00\x00\x00"}, 46) = 0 ioctl(3, PPPIOCGL2TPSTATS, 0) = -1 EFAULT (Bad address) exit_group(0) = ? [ 23.461621][ T24] audit: type=1400 audit(1792594422.430:64): avc: denied { execmem } for pid=297 comm="syz-executor207" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 23.481104][ T24] audit: type=1400 audit(1792594422.440:65): avc: denied { create } for pid=297 comm="syz-executor207" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 23.501068][ T24] audit: type=1400 audit(1792594422.440:66): avc: denied { connect } for pid=297 comm="syz-executor207" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 23.520923][ T24] audit: type=1400 audit(1792594422.450:67): avc: denied { ioctl } for pid=297 comm="syz-executor207" path="socket:[14473]" dev="sockfs" ino=14473 ioctlcmd=0x7436 scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 23.520983][ T297] ================================================================== [ 23.553893][ T297] BUG: KASAN: use-after-free in pppol2tp_sock_to_session+0x1a0/0x1b0 [ 23.561937][ T297] Read of size 4 at addr ffff888101b8a800 by task syz-executor207/297 [ 23.570084][ T297] [ 23.572427][ T297] CPU: 1 PID: 297 Comm: syz-executor207 Not tainted syzkaller #0 [ 23.580115][ T297] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 [ 23.590152][ T297] Call Trace: [ 23.593425][ T297] __dump_stack+0x21/0x24 [ 23.597725][ T297] dump_stack_lvl+0x1a7/0x208 [ 23.602372][ T297] ? show_regs_print_info+0x18/0x18 [ 23.607545][ T297] ? thaw_kernel_threads+0x220/0x220 [ 23.612807][ T297] ? __local_bh_enable_ip+0x53/0x80 [ 23.617979][ T297] print_address_description+0x7f/0x2c0 [ 23.623496][ T297] ? pppol2tp_sock_to_session+0x1a0/0x1b0 [ 23.629190][ T297] kasan_report+0x100/0x140 [ 23.633666][ T297] ? pppol2tp_sock_to_session+0x1a0/0x1b0 [ 23.639357][ T297] __asan_report_load4_noabort+0x14/0x20 [ 23.644964][ T297] pppol2tp_sock_to_session+0x1a0/0x1b0 [ 23.650479][ T297] pppol2tp_release+0x150/0x2b0 [ 23.655301][ T297] sock_close+0xb8/0x200 [ 23.659516][ T297] ? sock_mmap+0xa0/0xa0 [ 23.663732][ T297] __fput+0x2dc/0x730 [ 23.667688][ T297] ? _raw_spin_lock+0x94/0xf0 [ 23.672353][ T297] ____fput+0x15/0x20 [ 23.676310][ T297] task_work_run+0x127/0x190 [ 23.680871][ T297] do_exit+0xa7c/0x24e0 [ 23.685003][ T297] ? ptrace_notify+0x1ea/0x270 [ 23.689740][ T297] ? put_task_struct+0x90/0x90 [ 23.694473][ T297] ? do_notify_parent+0x810/0x810 [ 23.699469][ T297] do_group_exit+0x149/0x310 [ 23.704030][ T297] __x64_sys_exit_group+0x3f/0x40 [ 23.709027][ T297] do_syscall_64+0x31/0x40 [ 23.713415][ T297] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 23.719294][ T297] RIP: 0033:0x7fcd057e9305 [ 23.723688][ T297] Code: Unable to access opcode bytes at RIP 0x7fcd057e92db. [ 23.731035][ T297] RSP: 002b:00007ffe30cb24c8 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 [ 23.739429][ T297] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fcd057e9305 [ 23.747557][ T297] RDX: 00000000000000e7 RSI: ffffffffffffffd8 RDI: 0000000000000000 [ 23.755538][ T297] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffe30cb2658 [ 23.763495][ T297] R10: 00007ffe30cb2658 R11: 0000000000000206 R12: 0000000000000000 [ 23.771454][ T297] R13: 00007fcd0587f110 R14: 00007fcd058813a8 R15: 00007fcd058813c0 [ 23.779405][ T297] [ 23.781716][ T297] Allocated by task 297: [ 23.785938][ T297] __kasan_kmalloc+0xd4/0x100 [ 23.790584][ T297] __kmalloc+0x19f/0x330 [ 23.794796][ T297] l2tp_session_create+0x39/0xb60 [ 23.799793][ T297] pppol2tp_connect+0xbf5/0x1640 [ 23.804706][ T297] __sys_connect+0x3ce/0x450 [ 23.809266][ T297] __x64_sys_connect+0x7a/0x90 [ 23.814005][ T297] do_syscall_64+0x31/0x40 [ 23.818391][ T297] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 23.824254][ T297] [ 23.826559][ T297] Freed by task 7: [ 23.830256][ T297] kasan_set_track+0x4a/0x70 [ 23.834822][ T297] kasan_set_free_info+0x23/0x40 [ 23.839732][ T297] ____kasan_slab_free+0x125/0x160 [ 23.844825][ T297] __kasan_slab_free+0x11/0x20 [ 23.849586][ T297] slab_free_freelist_hook+0xc5/0x190 [ 23.854936][ T297] kfree+0xc0/0x270 [ 23.858718][ T297] l2tp_session_put+0xb2/0x1a0 [ 23.863457][ T297] l2tp_session_delete+0x3a9/0x4a0 [ 23.868541][ T297] l2tp_tunnel_del_work+0x180/0x3d0 [ 23.873713][ T297] process_one_work+0x6fd/0xbc0 [ 23.878540][ T297] worker_thread+0xa8e/0x13c0 [ 23.883191][ T297] kthread+0x324/0x3b0 [ 23.887245][ T297] ret_from_fork+0x1f/0x30 [ 23.891633][ T297] [ 23.893940][ T297] The buggy address belongs to the object at ffff888101b8a800 [ 23.893940][ T297] which belongs to the cache kmalloc-512 of size 512 [ 23.907965][ T297] The buggy address is located 0 bytes inside of [ 23.907965][ T297] 512-byte region [ffff888101b8a800, ffff888101b8aa00) [ 23.921060][ T297] The buggy address belongs to the page: [ 23.926692][ T297] page:ffffea000406e200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x101b88 [ 23.936902][ T297] head:ffffea000406e200 order:2 compound_mapcount:0 compound_pincount:0 [ 23.945199][ T297] flags: 0x4000000000010200(slab|head) [ 23.950636][ T297] raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080 [ 23.959197][ T297] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 [ 23.967764][ T297] page dumped because: kasan: bad access detected [ 23.974180][ T297] page_owner tracks the page as allocated [ 23.979891][ T297] page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 293, ts 23393689404, free_ts 17669209170 [ 23.998879][ T297] prep_new_page+0x176/0x190 [ 24.003446][ T297] get_page_from_freelist+0x225f/0x23f0 [ 24.008964][ T297] __alloc_pages_nodemask+0x29a/0x640 [ 24.014312][ T297] new_slab+0x84/0x3f0 [ 24.018356][ T297] ___slab_alloc+0x2f8/0x4c0 [ 24.022920][ T297] __slab_alloc+0x63/0xa0 [ 24.027247][ T297] __kmalloc_track_caller+0x1e4/0x310 [ 24.032610][ T297] __alloc_skb+0xdc/0x520 [ 24.036915][ T297] alloc_skb_with_frags+0xa3/0x560 [ 24.042024][ T297] sock_alloc_send_pskb+0x87f/0x9a0 [ 24.047215][ T297] unix_stream_sendmsg+0x4c9/0xbe0 [ 24.052322][ T297] sock_write_iter+0x2a6/0x3a0 [ 24.057060][ T297] vfs_write+0x770/0xd70 [ 24.061280][ T297] ksys_write+0x14a/0x260 [ 24.065585][ T297] __x64_sys_write+0x7b/0x90 [ 24.070149][ T297] do_syscall_64+0x31/0x40 [ 24.074542][ T297] page last free stack trace: [ 24.079217][ T297] free_unref_page_prepare+0x2b7/0x2d0 [ 24.084653][ T297] free_unref_page+0x7f/0x190 [ 24.089308][ T297] __put_page+0xae/0xe0 [ 24.093452][ T297] anon_pipe_buf_release+0x165/0x1f0 [ 24.098724][ T297] pipe_read+0x563/0x1050 [ 24.103042][ T297] vfs_read+0x62a/0xa50 [ 24.107177][ T297] ksys_read+0x14a/0x260 [ 24.111399][ T297] __x64_sys_read+0x7b/0x90 [ 24.115882][ T297] do_syscall_64+0x31/0x40 [ 24.120296][ T297] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 24.126168][ T297] [ 24.128474][ T297] Memory state around the buggy address: [ 24.134087][ T297] ffff888101b8a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.142129][ T297] ffff888101b8a780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.150170][ T297] >ffff888101b8a800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 24.158217][ T297] ^ [ 24.162268][ T297] ffff888101b8a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 24.170310][ T297] ffff888101b8a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 24.178347][ T297] ================================================================== [ 24.186382][ T297] Disabling lock debugging due to kernel taint [ 24.192787][ T297] ------------[ cut here ]------------ [ 24.197317][ T24] audit: type=1400 audit(1792594423.170:68): avc: denied { read } for pid=77 comm="syslogd" name="log" dev="sda1" ino=2010 scontext=system_u:system_r:syslogd_t tcontext=system_u:object_r:var_t tclass=lnk_file permissive=1 [ 24.198311][ T297] WARNING: CPU: 1 PID: 297 at net/l2tp/l2tp_ppp.c:156 pppol2tp_sock_to_session+0x167/0x1b0 [ 24.220095][ T24] audit: type=1400 audit(1792594423.170:69): avc: denied { search } for pid=77 comm="syslogd" name="/" dev="tmpfs" ino=1 scontext=system_u:system_r:syslogd_t tcontext=system_u:object_r:tmpfs_t tclass=dir permissive=1 [ 24.229862][ T297] Modules linked in: [ 24.251229][ T24] audit: type=1400 audit(1792594423.170:70): avc: denied { write } for pid=77 comm="syslogd" name="/" dev="tmpfs" ino=1 scontext=system_u:system_r:syslogd_t tcontext=system_u:object_r:tmpfs_t tclass=dir permissive=1 [ 24.254994][ T297] CPU: 1 PID: 297 Comm: syz-executor207 Tainted: G B syzkaller #0 [ 24.255005][ T297] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 [ 24.276281][ T24] audit: type=1400 audit(1792594423.170:71): avc: denied { add_name } for pid=77 comm="syslogd" name="messages" scontext=system_u:system_r:syslogd_t tcontext=system_u:object_r:tmpfs_t tclass=dir permissive=1 [ 24.285222][ T297] RIP: 0010:pppol2tp_sock_to_session+0x167/0x1b0 [ 24.285233][ T297] Code: 5d c3 e8 bc f7 34 fd be 02 00 00 00 eb 0a e8 b0 f7 34 fd be 01 00 00 00 4c 89 f7 e8 33 73 0e fe e9 0f ff ff ff e8 99 f7 34 fd <0f> 0b 48 89 df e8 ef 00 00 00 eb bd e8 88 f7 34 fd 4c 89 f7 be 03 [ 24.285239][ T297] RSP: 0018:ffffc90000b57c00 EFLAGS: 00010293 [ 24.285249][ T297] RAX: ffffffff842fbf27 RBX: ffff88811bea5000 RCX: ffff888105180000 [ 24.285263][ T297] RDX: 0000000000000000 RSI: 0000000000bfb000 RDI: 000000000c04eb7d [ 24.295712][ T24] audit: type=1400 audit(1792594423.170:72): avc: denied { create } for pid=77 comm="syslogd" name="messages" scontext=system_u:system_r:syslogd_t tcontext=system_u:object_r:tmpfs_t tclass=file permissive=1 [ 24.315752][ T297] RBP: ffffc90000b57c20 R08: 0000000000000003 R09: 0000000000000004 [ 24.322187][ T24] audit: type=1400 audit(1792594423.170:73): avc: denied { append open } for pid=77 comm="syslogd" path="/tmp/messages" dev="tmpfs" ino=5 scontext=system_u:system_r:syslogd_t tcontext=system_u:object_r:tmpfs_t tclass=file permissive=1 [ 24.341681][ T297] R10: dffffc0000000000 R11: fffffbfff0dcf848 R12: dffffc0000000000 [ 24.422644][ T297] R13: dffffc0000000000 R14: 0000000000bfb000 R15: ffff888101b8a800 [ 24.430633][ T297] FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 [ 24.439570][ T297] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 24.446159][ T297] CR2: 00007fcd05886230 CR3: 000000000640f000 CR4: 00000000003506a0 [ 24.454134][ T297] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 24.462089][ T297] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 24.470058][ T297] Call Trace: [ 24.473353][ T297] pppol2tp_release+0x150/0x2b0 [ 24.478177][ T297] sock_close+0xb8/0x200 [ 24.482389][ T297] ? sock_mmap+0xa0/0xa0 [ 24.486631][ T297] __fput+0x2dc/0x730 [ 24.490604][ T297] ? _raw_spin_lock+0x94/0xf0 [ 24.495279][ T297] ____fput+0x15/0x20 [ 24.499251][ T297] task_work_run+0x127/0x190 [ 24.503843][ T297] do_exit+0xa7c/0x24e0 [ 24.507985][ T297] ? ptrace_notify+0x1ea/0x270 [ 24.512723][ T297] ? put_task_struct+0x90/0x90 [ 24.517494][ T297] ? do_notify_parent+0x810/0x810 [ 24.522505][ T297] do_group_exit+0x149/0x310 [ 24.527109][ T297] __x64_sys_exit_group+0x3f/0x40 [ 24.532118][ T297] do_syscall_64+0x31/0x40 [ 24.536546][ T297] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 24.542419][ T297] RIP: 0033:0x7fcd057e9305 [ 24.546828][ T297] Code: Unable to access opcode bytes at RIP 0x7fcd057e92db. [ 24.554191][ T297] RSP: 002b:00007ffe30cb24c8 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 +++ exited with 0 +++ [ 24.562575][ T297] RAX: ffffffffffffffda RBX