[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.24' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 42.045805] audit: type=1400 audit(1602021682.969:8): avc: denied { execmem } for pid=6484 comm="syz-executor114" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 42.059960] ================================================================================ [ 42.074505] UBSAN: Undefined behaviour in fs/f2fs/super.c:2227:16 [ 42.080789] shift exponent 55 is too large for 32-bit type 'int' [ 42.086933] CPU: 1 PID: 6484 Comm: syz-executor114 Not tainted 4.19.149-syzkaller #0 [ 42.094808] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.104175] Call Trace: [ 42.106783] dump_stack+0x22c/0x33e [ 42.110437] ubsan_epilogue+0xe/0x3a [ 42.114167] __ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 [ 42.120366] ? __bread_gfp+0x81/0x300 [ 42.124173] f2fs_fill_super.cold+0x1f9/0x5fb [ 42.128677] ? vsnprintf+0x2cc/0x14f0 [ 42.132505] ? lock_downgrade+0x750/0x750 [ 42.136751] ? snprintf+0xbb/0xf0 [ 42.140234] ? f2fs_commit_super+0x400/0x400 [ 42.144662] ? __mutex_add_waiter+0x160/0x160 [ 42.149279] ? set_blocksize+0x163/0x3f0 [ 42.153354] mount_bdev+0x2fc/0x3b0 [ 42.157014] ? f2fs_commit_super+0x400/0x400 [ 42.161460] mount_fs+0xa3/0x318 [ 42.164863] vfs_kern_mount.part.0+0x68/0x470 [ 42.169384] do_mount+0x51c/0x2f10 [ 42.172939] ? check_preemption_disabled+0x41/0x2b0 [ 42.177965] ? copy_mount_string+0x40/0x40 [ 42.182251] ? kmem_cache_alloc_trace+0x379/0x4b0 [ 42.187120] ? _copy_from_user+0xd2/0x130 [ 42.191281] ? copy_mount_options+0x261/0x370 [ 42.195794] ksys_mount+0xcf/0x130 [ 42.199358] __x64_sys_mount+0xba/0x150 [ 42.203423] ? lockdep_hardirqs_on+0x3c1/0x5e0 [ 42.208012] do_syscall_64+0xf9/0x670 [ 42.211818] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.217030] RIP: 0033:0x44776a [ 42.220226] Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00 [ 42.239128] RSP: 002b:00007ffd90cf80d8 EFLAGS: 00000297 ORIG_RAX: 00000000000000a5 [ 42.246842] RAX: ffffffffffffffda RBX: 00007ffd90cf8130 RCX: 000000000044776a [ 42.254132] RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffd90cf80f0 [ 42.261396] RBP: 00007ffd90cf80f0 R08: 00007ffd90cf8130 R09: 00007ffd00000015 [ 42.268746] R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000045 [ 42.276022] R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003 [ 42.283300] ================================================================================ [ 42.293464] F2FS-fs (loop0): Invalid blocksize (8388608), supports only 4KB [ 42.293464] [ 42.302298] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock [ 42.311011] F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0) [ 42.318772] F2FS-fs (loop0): Can't find valid F2FS filesystem in 2th superblock [ 42.326697] F2FS-fs (loop0): Invalid blocksize (8388608), supports only 4KB [ 42.326697] [ 42.335991] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock [ 42.343630] F2FS-fs (loop0): Magic Mism