ci2-android-5-10/strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ci2-android-5-10/syz-executor2752232847 <...> Warning: Permanently added '10.128.0.246' (ED25519) to the list of known hosts. execve("ci2-android-5-10/syz-executor2752232847", ["ci2-android-5-10/syz-executor2752232847"], 0x7ffdbcbac260 /* 10 vars */) = 0 brk(NULL) = 0x55557c93a000 brk(0x55557c93ad40) = 0x55557c93ad40 arch_prctl(ARCH_SET_FS, 0x55557c93a3c0) = 0 set_tid_address(0x55557c93a690) = 297 set_robust_list(0x55557c93a6a0, 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-executor2752232847", 4096) = 45 getrandom("\x23\x84\x6c\x72\x40\x0a\x8c\x8b", 8, GRND_NONBLOCK) = 8 brk(NULL) = 0x55557c93ad40 brk(0x55557c95bd40) = 0x55557c95bd40 brk(0x55557c95c000) = 0x55557c95c000 mprotect(0x7fdb371eb000, 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\x00\x00\x00\x00\x04\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x20\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00"}, 50) = 0 sendfile(-1, -1, [3], 2757) = -1 EBADF (Bad file descriptor) clone3({flags=CLONE_UNTRACED|CLONE_CHILD_SETTID|CLONE_NEWCGROUP|CLONE_NEWPID, child_tid=NULL, exit_signal=SIGRT_7, stack=NULL, stack_size=0, cgroup=4294967295}, 88) = 298 ioctl(3, PPPIOCSMRU, 0) = -1 ENOSYS (Function not implemented) exit_group(0) = ? +++ exited with 0 +++ [ 20.193895][ T24] audit: type=1400 audit(1792500137.049:64): avc: denied { execmem } for pid=297 comm="syz-executor275" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 20.213314][ T24] audit: type=1400 audit(1792500137.059:65): avc: denied { create } for pid=297 comm="syz-executor275" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 20.233217][ T24] audit: type=1400 audit(1792500137.059:66): avc: denied { connect } for pid=297 comm="syz-executor275" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 20.253053][ T24] audit: type=1400 audit(1792500137.099:67): avc: denied { ioctl } for pid=297 comm="syz-executor275" path="socket:[1600]" dev="sockfs" ino=1600 ioctlcmd=0x7452 scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 20.395608][ T298] ================================================================== [ 20.403709][ T298] BUG: KASAN: use-after-free in pppol2tp_sock_to_session+0x1a0/0x1b0 [ 20.412112][ T298] Read of size 4 at addr ffff888101b87c00 by task syz-executor275/298 [ 20.420232][ T298] [ 20.422551][ T298] CPU: 1 PID: 298 Comm: syz-executor275 Not tainted syzkaller #0 [ 20.430232][ T298] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 [ 20.440267][ T298] Call Trace: [ 20.443534][ T298] __dump_stack+0x21/0x24 [ 20.447838][ T298] dump_stack_lvl+0x1a7/0x208 [ 20.452482][ T298] ? show_regs_print_info+0x18/0x18 [ 20.457826][ T298] ? thaw_kernel_threads+0x220/0x220 [ 20.463100][ T298] ? __local_bh_enable_ip+0x53/0x80 [ 20.468274][ T298] print_address_description+0x7f/0x2c0 [ 20.473792][ T298] ? pppol2tp_sock_to_session+0x1a0/0x1b0 [ 20.479485][ T298] kasan_report+0x100/0x140 [ 20.483960][ T298] ? pppol2tp_sock_to_session+0x1a0/0x1b0 [ 20.489653][ T298] __asan_report_load4_noabort+0x14/0x20 [ 20.495257][ T298] pppol2tp_sock_to_session+0x1a0/0x1b0 [ 20.500775][ T298] pppol2tp_release+0x150/0x2b0 [ 20.505596][ T298] sock_close+0xb8/0x200 [ 20.509803][ T298] ? sock_mmap+0xa0/0xa0 [ 20.514028][ T298] __fput+0x2dc/0x730 [ 20.517979][ T298] ____fput+0x15/0x20 [ 20.521938][ T298] task_work_run+0x127/0x190 [ 20.526498][ T298] do_exit+0xa7c/0x24e0 [ 20.530625][ T298] ? __kasan_check_write+0x14/0x20 [ 20.535708][ T298] ? switch_fpu_return+0x19c/0x330 [ 20.540785][ T298] ? put_task_struct+0x90/0x90 [ 20.545516][ T298] ? fpu__clear_all+0x20/0x20 [ 20.550165][ T298] ? __kasan_check_read+0x11/0x20 [ 20.555162][ T298] __x64_sys_exit+0x40/0x40 [ 20.559641][ T298] do_syscall_64+0x31/0x40 [ 20.564034][ T298] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 20.569902][ T298] RIP: 0033:0x7fdb3715ad79 [ 20.574292][ T298] Code: Unable to access opcode bytes at RIP 0x7fdb3715ad4f. [ 20.581628][ T298] RSP: 002b:00007ffd134dfda8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c [ 20.590015][ T298] RAX: ffffffffffffffda RBX: 0000200000000040 RCX: 00007fdb3715ad79 [ 20.597964][ T298] RDX: 00007fdb3716c557 RSI: 0000000000000000 RDI: 0000000000000000 [ 20.605910][ T298] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000023800000 [ 20.613881][ T298] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd134dffc8 [ 20.621827][ T298] R13: 0000000000000002 R14: 00007fdb371ebca0 R15: 0000000000000002 [ 20.629778][ T298] [ 20.632080][ T298] Allocated by task 297: [ 20.636301][ T298] __kasan_kmalloc+0xd4/0x100 [ 20.640950][ T298] __kmalloc+0x19f/0x330 [ 20.645168][ T298] l2tp_session_create+0x39/0xb60 [ 20.650165][ T298] pppol2tp_connect+0xbf5/0x1640 [ 20.655078][ T298] __sys_connect+0x3ce/0x450 [ 20.659639][ T298] __x64_sys_connect+0x7a/0x90 [ 20.664377][ T298] do_syscall_64+0x31/0x40 [ 20.668767][ T298] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 20.674629][ T298] [ 20.676931][ T298] Freed by task 49: [ 20.680713][ T298] kasan_set_track+0x4a/0x70 [ 20.685279][ T298] kasan_set_free_info+0x23/0x40 [ 20.690193][ T298] ____kasan_slab_free+0x125/0x160 [ 20.695287][ T298] __kasan_slab_free+0x11/0x20 [ 20.700109][ T298] slab_free_freelist_hook+0xc5/0x190 [ 20.705558][ T298] kfree+0xc0/0x270 [ 20.709363][ T298] l2tp_session_put+0xb2/0x1a0 [ 20.714102][ T298] l2tp_session_delete+0x3a9/0x4a0 [ 20.719187][ T298] l2tp_tunnel_del_work+0x180/0x3d0 [ 20.724358][ T298] process_one_work+0x6fd/0xbc0 [ 20.729180][ T298] worker_thread+0xa8e/0x13c0 [ 20.733833][ T298] kthread+0x324/0x3b0 [ 20.737874][ T298] ret_from_fork+0x1f/0x30 [ 20.742264][ T298] [ 20.744573][ T298] The buggy address belongs to the object at ffff888101b87c00 [ 20.744573][ T298] which belongs to the cache kmalloc-512 of size 512 [ 20.758599][ T298] The buggy address is located 0 bytes inside of [ 20.758599][ T298] 512-byte region [ffff888101b87c00, ffff888101b87e00) [ 20.771675][ T298] The buggy address belongs to the page: [ 20.777311][ T298] page:ffffea000406e100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x101b84 [ 20.787610][ T298] head:ffffea000406e100 order:2 compound_mapcount:0 compound_pincount:0 [ 20.795928][ T298] flags: 0x4000000000010200(slab|head) [ 20.801366][ T298] raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080 [ 20.809930][ T298] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 [ 20.818488][ T298] page dumped because: kasan: bad access detected [ 20.824885][ T298] page_owner tracks the page as allocated [ 20.830590][ T298] 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 20126948683, free_ts 20052460426 [ 20.849582][ T298] prep_new_page+0x176/0x190 [ 20.854153][ T298] get_page_from_freelist+0x225f/0x23f0 [ 20.859675][ T298] __alloc_pages_nodemask+0x29a/0x640 [ 20.865053][ T298] new_slab+0x84/0x3f0 [ 20.869099][ T298] ___slab_alloc+0x2f8/0x4c0 [ 20.873664][ T298] __slab_alloc+0x63/0xa0 [ 20.877968][ T298] __kmalloc_track_caller+0x1e4/0x310 [ 20.883314][ T298] __alloc_skb+0xdc/0x520 [ 20.887622][ T298] alloc_skb_with_frags+0xa3/0x560 [ 20.892709][ T298] sock_alloc_send_pskb+0x87f/0x9a0 [ 20.897895][ T298] unix_stream_sendmsg+0x4c9/0xbe0 [ 20.903048][ T298] sock_write_iter+0x2a6/0x3a0 [ 20.907997][ T298] vfs_write+0x770/0xd70 [ 20.912227][ T298] ksys_write+0x14a/0x260 [ 20.916560][ T298] __x64_sys_write+0x7b/0x90 [ 20.921134][ T298] do_syscall_64+0x31/0x40 [ 20.925523][ T298] page last free stack trace: [ 20.930180][ T298] __free_pages_ok+0x80b/0x830 [ 20.934919][ T298] __free_pages+0xd8/0x390 [ 20.939310][ T298] __free_slab+0xcf/0x190 [ 20.943612][ T298] unfreeze_partials+0x150/0x180 [ 20.948610][ T298] put_cpu_partial+0xc1/0x180 [ 20.953526][ T298] __slab_free+0x2c9/0x3a0 [ 20.957919][ T298] ___cache_free+0x10e/0x130 [ 20.962487][ T298] qlink_free+0x50/0x90 [ 20.966624][ T298] qlist_free_all+0x5f/0xb0 [ 20.971205][ T298] kasan_quarantine_reduce+0x14a/0x160 [ 20.976637][ T298] __kasan_slab_alloc+0x2f/0xe0 [ 20.981466][ T298] slab_post_alloc_hook+0x5d/0x2f0 [ 20.986621][ T298] kmem_cache_alloc+0x15a/0x2d0 [ 20.991444][ T298] vm_area_alloc+0x24/0x160 [ 20.995917][ T298] mmap_region+0xa5e/0x19c0 [ 21.000412][ T298] do_mmap+0x85f/0xf50 [ 21.004463][ T298] [ 21.006858][ T298] Memory state around the buggy address: [ 21.012467][ T298] ffff888101b87b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.020503][ T298] ffff888101b87b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.028548][ T298] >ffff888101b87c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.036589][ T298] ^ [ 21.040650][ T298] ffff888101b87c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.048689][ T298] ffff888101b87d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.056744][ T298] ================================================================== [ 21.064779][ T298] Disabling lock debugging due to kernel taint [ 21.071158][ T298] ------------[ cut here ]------------ [ 21.076924][ T298] WARNING: CPU: 1 PID: 298 at net/l2tp/l2tp_ppp.c:156 pppol2tp_sock_to_session+0x167/0x1b0 [ 21.079887][ T24] audit: type=1400 audit(1792500137.939:68): 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 [ 21.086939][ T298] Modules linked in: [ 21.108614][ T24] audit: type=1400 audit(1792500137.939:69): 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 [ 21.112819][ T298] CPU: 1 PID: 298 Comm: syz-executor275 Tainted: G B syzkaller #0 [ 21.133870][ T24] audit: type=1400 audit(1792500137.939:70): 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 [ 21.142959][ T298] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 [ 21.164252][ T24] audit: type=1400 audit(1792500137.939:71): 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 [ 21.174289][ T298] RIP: 0010:pppol2tp_sock_to_session+0x167/0x1b0 [ 21.194702][ T24] audit: type=1400 audit(1792500137.939:72): 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 [ 21.201287][ T298] 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 [ 21.221254][ T24] audit: type=1400 audit(1792500137.939:73): 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 [ 21.240895][ T298] RSP: 0018:ffffc90000b07c40 EFLAGS: 00010293 [ 21.269560][ T298] RAX: ffffffff842fbf27 RBX: ffff88811f05c800 RCX: ffff88811f003c00 [ 21.277530][ T298] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000c04eb7d [ 21.285528][ T298] RBP: ffffc90000b07c60 R08: 0000000000000003 R09: 0000000000000004 [ 21.293485][ T298] R10: dffffc0000000000 R11: fffffbfff0dcf848 R12: dffffc0000000000 [ 21.301462][ T298] R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888101b87c00 [ 21.309719][ T298] FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 [ 21.318746][ T298] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.325329][ T298] CR2: 00007fdb3716c4f0 CR3: 000000010d6f7000 CR4: 00000000003506a0 [ 21.333277][ T298] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 21.341263][ T298] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 21.349239][ T298] Call Trace: [ 21.352507][ T298] pppol2tp_release+0x150/0x2b0 [ 21.357364][ T298] sock_close+0xb8/0x200 [ 21.361608][ T298] ? sock_mmap+0xa0/0xa0 [ 21.365956][ T298] __fput+0x2dc/0x730 [ 21.369923][ T298] ____fput+0x15/0x20 [ 21.373913][ T298] task_work_run+0x127/0x190 [ 21.378508][ T298] do_exit+0xa7c/0x24e0 [ 21.382648][ T298] ? __kasan_check_write+0x14/0x20 [ 21.387759][ T298] ? switch_fpu_return+0x19c/0x330 [ 21.392874][ T298] ? put_task_struct+0x90/0x90 [ 21.397639][ T298] ? fpu__clear_all+0x20/0x20 [ 21.402315][ T298] ? __kasan_check_read+0x11/0x20 [ 21.407377][ T298] __x64_sys_exit+0x40/0x40 [ 21.411866][ T298] do_syscall_64+0x31/0x40 [ 21.416289][ T298] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 21.422166][ T298] RIP: 0033:0x7fdb3715ad79 [ 21.426578][ T298] Code: Unable to access opcode bytes at RIP 0x7fdb3715ad4f. [ 21.433927][ T298] RSP: 002b:00007ffd134dfda8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c [ 21.442437][ T298] RAX: ffffffffffffffda RBX: 0000200000000040 RCX: 00007fdb3715ad79