================================================================================ UBSAN: Undefined behaviour in fs/ext4/super.c:3763:25 shift exponent 255 is too large for 32-bit type 'int' CPU: 1 PID: 9955 Comm: syz-executor.4 Not tainted 4.19.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x22c/0x33e lib/dump_stack.c:118 ubsan_epilogue+0xe/0x3a lib/ubsan.c:161 __ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 lib/ubsan.c:422 ext4_fill_super.cold+0x33b/0x4ea fs/ext4/super.c:3763 mount_bdev+0x2fc/0x3b0 fs/super.c:1158 mount_fs+0xa3/0x318 fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2469 [inline] do_mount+0x51c/0x2f10 fs/namespace.c:2799 ksys_mount+0xcf/0x130 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3026 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4608aa Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad 89 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 8a 89 fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007f3584070a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f3584070b20 RCX: 00000000004608aa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f3584070ae0 RBP: 00007f3584070ae0 R08: 00007f3584070b20 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020012900 ================================================================================ EXT4-fs (loop4): Unsupported filesystem blocksize 0 (255 log_block_size) EXT4-fs (loop4): Unsupported filesystem blocksize 0 (255 log_block_size) audit: type=1800 audit(1603021001.248:23): pid=10011 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="syz-executor.0" name="file0" dev="sda1" ino=15957 res=0 audit: type=1804 audit(1603021002.428:24): pid=10114 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir570416356/syzkaller.QwznO5/57/file0" dev="sda1" ino=15970 res=1 nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. audit: type=1400 audit(1603021003.978:25): avc: denied { create } for pid=10227 comm="syz-executor.1" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dccp_socket permissive=1 EXT4-fs (loop4): Invalid log cluster size: 22784 EXT4-fs (loop4): Invalid log cluster size: 22784 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'. EXT4-fs (loop0): Invalid journal IO priority (must be 0-7) netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'. xt_l2tp: v2 doesn't support IP mode audit: type=1400 audit(1603021006.958:26): avc: denied { name_bind } for pid=10474 comm="syz-executor.4" src=20000 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:port_t:s0 tclass=dccp_socket permissive=1 audit: type=1400 audit(1603021006.998:27): avc: denied { node_bind } for pid=10474 comm="syz-executor.4" src=20000 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:node_t:s0 tclass=dccp_socket permissive=1 audit: type=1400 audit(1603021007.098:28): avc: denied { name_connect } for pid=10474 comm="syz-executor.4" dest=20000 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:port_t:s0 tclass=dccp_socket permissive=1 [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] semctl(GETNCNT/GETZCNT) is since 3.16 Single Unix Specification compliant. The task syz-executor.3 (10612) triggered the difference, watch for misbehavior. [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] [U] audit: type=1804 audit(1603021009.158:29): pid=10624 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir456737206/syzkaller.mJm2Yh/125/memory.events" dev="sda1" ino=16001 res=1 Failed to obtain node identity Enabling of bearer rejected, failed to enable media Failed to obtain node identity Enabling of bearer rejected, failed to enable media audit: type=1804 audit(1603021009.438:30): pid=10641 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir456737206/syzkaller.mJm2Yh/125/memory.events" dev="sda1" ino=16001 res=1 Failed to obtain node identity Enabling of bearer rejected, failed to enable media audit: type=1804 audit(1603021009.938:31): pid=10665 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir948583825/syzkaller.ZxUcPu/119/file1/file0" dev="loop1" ino=15 res=1