ci2-android-5-10/strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ci2-android-5-10/syz-executor1132907591 <...> Warning: Permanently added '10.128.10.15' (ED25519) to the list of known hosts. execve("ci2-android-5-10/syz-executor1132907591", ["ci2-android-5-10/syz-executor1132907591"], 0x7fffcb732250 /* 10 vars */) = 0 brk(NULL) = 0x555560569000 brk(0x555560569d40) = 0x555560569d40 arch_prctl(ARCH_SET_FS, 0x5555605693c0) = 0 set_tid_address(0x555560569690) = 297 set_robust_list(0x5555605696a0, 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-executor1132907591", 4096) = 45 getrandom("\x0c\x2c\x04\x70\x7d\x58\xa3\x43", 8, GRND_NONBLOCK) = 8 brk(NULL) = 0x555560569d40 brk(0x55556058ad40) = 0x55556058ad40 brk(0x55556058b000) = 0x55556058b000 mprotect(0x7fd0f5cc5000, 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 write(1, "executing program\n", 18) = 18 executing program 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 +++ [ 18.875549][ T24] audit: type=1400 audit(1793432583.019:64): avc: denied { execmem } for pid=297 comm="syz-executor113" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 18.879969][ T24] audit: type=1400 audit(1793432583.019:65): avc: denied { create } for pid=297 comm="syz-executor113" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 18.883266][ T24] audit: type=1400 audit(1793432583.019:66): avc: denied { connect } for pid=297 comm="syz-executor113" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 18.886813][ T24] audit: type=1400 audit(1793432583.029:67): avc: denied { ioctl } for pid=297 comm="syz-executor113" path="socket:[13985]" dev="sockfs" ino=13985 ioctlcmd=0x7452 scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=pppox_socket permissive=1 [ 19.037898][ T298] ================================================================== [ 19.045993][ T298] BUG: KASAN: use-after-free in pppol2tp_sock_to_session+0x1a0/0x1b0 [ 19.054027][ T298] Read of size 4 at addr ffff8881200a6000 by task syz-executor113/298 [ 19.062150][ T298] [ 19.064463][ T298] CPU: 1 PID: 298 Comm: syz-executor113 Not tainted syzkaller #0 [ 19.072148][ T298] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 [ 19.082198][ T298] Call Trace: [ 19.085558][ T298] __dump_stack+0x21/0x24 [ 19.089856][ T298] dump_stack_lvl+0x1a7/0x208 [ 19.094503][ T298] ? show_regs_print_info+0x18/0x18 [ 19.099670][ T298] ? thaw_kernel_threads+0x220/0x220 [ 19.104927][ T298] ? __local_bh_enable_ip+0x53/0x80 [ 19.110183][ T298] print_address_description+0x7f/0x2c0 [ 19.115819][ T298] ? pppol2tp_sock_to_session+0x1a0/0x1b0 [ 19.121515][ T298] kasan_report+0x100/0x140 [ 19.125990][ T298] ? pppol2tp_sock_to_session+0x1a0/0x1b0 [ 19.131681][ T298] __asan_report_load4_noabort+0x14/0x20 [ 19.137300][ T298] pppol2tp_sock_to_session+0x1a0/0x1b0 [ 19.142827][ T298] pppol2tp_release+0x150/0x2b0 [ 19.147735][ T298] sock_close+0xb8/0x200 [ 19.151948][ T298] ? sock_mmap+0xa0/0xa0 [ 19.156157][ T298] __fput+0x2dc/0x730 [ 19.160112][ T298] ____fput+0x15/0x20 [ 19.164065][ T298] task_work_run+0x127/0x190 [ 19.168626][ T298] do_exit+0xa7c/0x24e0 [ 19.172754][ T298] ? __kasan_check_write+0x14/0x20 [ 19.177838][ T298] ? switch_fpu_return+0x19c/0x330 [ 19.182919][ T298] ? put_task_struct+0x90/0x90 [ 19.187663][ T298] ? fpu__clear_all+0x20/0x20 [ 19.192313][ T298] ? __kasan_check_read+0x11/0x20 [ 19.197305][ T298] __x64_sys_exit+0x40/0x40 [ 19.201793][ T298] do_syscall_64+0x31/0x40 [ 19.206194][ T298] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 19.212055][ T298] RIP: 0033:0x7fd0f5c34d79 [ 19.216435][ T298] Code: Unable to access opcode bytes at RIP 0x7fd0f5c34d4f. [ 19.223769][ T298] RSP: 002b:00007ffe79314fc8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c [ 19.232148][ T298] RAX: ffffffffffffffda RBX: 0000200000000040 RCX: 00007fd0f5c34d79 [ 19.240091][ T298] RDX: 00007fd0f5c46557 RSI: 0000000000000000 RDI: 0000000000000000 [ 19.248036][ T298] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000023800000 [ 19.255980][ T298] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe793151e8 [ 19.263924][ T298] R13: 0000000000000002 R14: 00007fd0f5cc5ca0 R15: 0000000000000002 [ 19.271868][ T298] [ 19.274167][ T298] Allocated by task 297: [ 19.278385][ T298] __kasan_kmalloc+0xd4/0x100 [ 19.283030][ T298] __kmalloc+0x19f/0x330 [ 19.287238][ T298] l2tp_session_create+0x39/0xb60 [ 19.292241][ T298] pppol2tp_connect+0xbf5/0x1640 [ 19.297146][ T298] __sys_connect+0x3ce/0x450 [ 19.301706][ T298] __x64_sys_connect+0x7a/0x90 [ 19.306450][ T298] do_syscall_64+0x31/0x40 [ 19.310838][ T298] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 19.316690][ T298] [ 19.318987][ T298] Freed by task 49: [ 19.322773][ T298] kasan_set_track+0x4a/0x70 [ 19.327333][ T298] kasan_set_free_info+0x23/0x40 [ 19.332243][ T298] ____kasan_slab_free+0x125/0x160 [ 19.337328][ T298] __kasan_slab_free+0x11/0x20 [ 19.342065][ T298] slab_free_freelist_hook+0xc5/0x190 [ 19.347412][ T298] kfree+0xc0/0x270 [ 19.351189][ T298] l2tp_session_put+0xb2/0x1a0 [ 19.355921][ T298] l2tp_session_delete+0x3a9/0x4a0 [ 19.361003][ T298] l2tp_tunnel_del_work+0x180/0x3d0 [ 19.366167][ T298] process_one_work+0x6fd/0xbc0 [ 19.370983][ T298] worker_thread+0xa8e/0x13c0 [ 19.375628][ T298] kthread+0x324/0x3b0 [ 19.379662][ T298] ret_from_fork+0x1f/0x30 [ 19.384056][ T298] [ 19.386365][ T298] The buggy address belongs to the object at ffff8881200a6000 [ 19.386365][ T298] which belongs to the cache kmalloc-512 of size 512 [ 19.400386][ T298] The buggy address is located 0 bytes inside of [ 19.400386][ T298] 512-byte region [ffff8881200a6000, ffff8881200a6200) [ 19.413452][ T298] The buggy address belongs to the page: [ 19.419075][ T298] page:ffffea0004802900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1200a4 [ 19.429279][ T298] head:ffffea0004802900 order:2 compound_mapcount:0 compound_pincount:0 [ 19.437572][ T298] flags: 0x4000000000010200(slab|head) [ 19.443003][ T298] raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080 [ 19.451564][ T298] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 [ 19.460119][ T298] page dumped because: kasan: bad access detected [ 19.466520][ T298] page_owner tracks the page as allocated [ 19.472221][ 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 18802213249, free_ts 0 [ 19.490335][ T298] prep_new_page+0x176/0x190 [ 19.494916][ T298] get_page_from_freelist+0x225f/0x23f0 [ 19.500457][ T298] __alloc_pages_nodemask+0x29a/0x640 [ 19.505806][ T298] new_slab+0x84/0x3f0 [ 19.509846][ T298] ___slab_alloc+0x2f8/0x4c0 [ 19.514401][ T298] __slab_alloc+0x63/0xa0 [ 19.518697][ T298] __kmalloc_track_caller+0x1e4/0x310 [ 19.524037][ T298] __alloc_skb+0xdc/0x520 [ 19.528338][ T298] alloc_skb_with_frags+0xa3/0x560 [ 19.533420][ T298] sock_alloc_send_pskb+0x87f/0x9a0 [ 19.538588][ T298] unix_stream_sendmsg+0x4c9/0xbe0 [ 19.543685][ T298] sock_write_iter+0x2a6/0x3a0 [ 19.548414][ T298] vfs_write+0x770/0xd70 [ 19.552624][ T298] ksys_write+0x14a/0x260 [ 19.556932][ T298] __x64_sys_write+0x7b/0x90 [ 19.561492][ T298] do_syscall_64+0x31/0x40 [ 19.565872][ T298] page_owner free stack trace missing [ 19.571207][ T298] [ 19.573500][ T298] Memory state around the buggy address: [ 19.579113][ T298] ffff8881200a5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.587157][ T298] ffff8881200a5f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.595186][ T298] >ffff8881200a6000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 19.603213][ T298] ^ [ 19.607248][ T298] ffff8881200a6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 19.615278][ T298] ffff8881200a6100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 19.623317][ T298] ================================================================== [ 19.631344][ T298] Disabling lock debugging due to kernel taint [ 19.637678][ T298] ------------[ cut here ]------------ [ 19.643171][ T298] WARNING: CPU: 1 PID: 298 at net/l2tp/l2tp_ppp.c:156 pppol2tp_sock_to_session+0x167/0x1b0 [ 19.653139][ T298] Modules linked in: [ 19.657024][ T298] CPU: 1 PID: 298 Comm: syz-executor113 Tainted: G B syzkaller #0 [ 19.666127][ T24] audit: type=1400 audit(1793432583.789:68): 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 [ 19.666338][ T298] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 [ 19.687880][ T24] audit: type=1400 audit(1793432583.789:69): 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 [ 19.698010][ T298] RIP: 0010:pppol2tp_sock_to_session+0x167/0x1b0 [ 19.719095][ T24] audit: type=1400 audit(1793432583.789:70): 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 [ 19.725566][ T298] Code: 5d c3 e8 ec bd 34 fd be 02 00 00 00 eb 0a e8 e0 bd 34 fd be 01 00 00 00 4c 89 f7 e8 f3 3b 0e fe e9 0f ff ff ff e8 c9 bd 34 fd <0f> 0b 48 89 df e8 ef 00 00 00 eb bd e8 b8 bd 34 fd 4c 89 f7 be 03 [ 19.746578][ T24] audit: type=1400 audit(1793432583.789:71): 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 [ 19.766185][ T298] RSP: 0018:ffffc9000096fc40 EFLAGS: 00010293 [ 19.786749][ T24] audit: type=1400 audit(1793432583.789:72): 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 [ 19.792694][ T298] RAX: ffffffff842ff8f7 RBX: ffff88811b38f000 RCX: ffff888120050000 [ 19.813031][ T24] audit: type=1400 audit(1793432583.789:73): 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 [ 19.820946][ T298] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000c04eb7d [ 19.851604][ T298] RBP: ffffc9000096fc60 R08: 0000000000000003 R09: 0000000000000004 [ 19.859551][ T298] R10: dffffc0000000000 R11: fffffbfff0dcfa48 R12: dffffc0000000000 [ 19.867517][ T298] R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881200a6000 [ 19.875484][ T298] FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 [ 19.884405][ T298] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 19.890984][ T298] CR2: 00007fd0f5c464f0 CR3: 000000010d4bb000 CR4: 00000000003506a0 [ 19.898929][ T298] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 19.906892][ T298] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 19.914853][ T298] Call Trace: [ 19.918131][ T298] pppol2tp_release+0x150/0x2b0 [ 19.923002][ T298] sock_close+0xb8/0x200 [ 19.927228][ T298] ? sock_mmap+0xa0/0xa0 [ 19.931494][ T298] __fput+0x2dc/0x730 [ 19.935458][ T298] ____fput+0x15/0x20 [ 19.940516][ T298] task_work_run+0x127/0x190 [ 19.945093][ T298] do_exit+0xa7c/0x24e0 [ 19.949220][ T298] ? __kasan_check_write+0x14/0x20 [ 19.954337][ T298] ? switch_fpu_return+0x19c/0x330 [ 19.959432][ T298] ? put_task_struct+0x90/0x90 [ 19.964198][ T298] ? fpu__clear_all+0x20/0x20 [ 19.968863][ T298] ? __kasan_check_read+0x11/0x20 [ 19.973987][ T298] __x64_sys_exit+0x40/0x40 [ 19.978483][ T298] do_syscall_64+0x31/0x40 [ 19.982913][ T298] entry_SYSCALL_64_after_hwframe+0x61/0xcb [ 19.988783][ T298] RIP: 0033:0x7fd0f5c34d79 [ 19.993191][ T298] Code: Unable to access opcode bytes at RIP 0x7fd0f5c34d4f. [ 20.000548][ T298] RSP: 002b:00007ffe79314fc8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c [ 20.008928][ T298] RAX: ffffffffffffffda RBX: 0000200000000040 RCX: 00007fd0f5c34d79 [ 20.016894][ T298] RDX: 00007fd0f5c46557 RSI: 0000000000000000 RDI: 0000000000000000 [ 20.024857][ T298] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000023800000 [ 20.032840][ T298] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe793151e8 [ 20.040805][