bisecting fixing commit since 87335852c5d9ec629f80bb2257b9a9945962b719 building syzkaller on e34b696c0d7c04dbc824dee8b5123969bbca19b7 testing commit 87335852c5d9ec629f80bb2257b9a9945962b719 with gcc (GCC) 8.4.1 20210217 kernel signature: e93a577bd81be6186519d619afb437d24094c1a7d680b98acfc4b92757ba3a3f all runs: crashed: divide error in squashfs_readpage testing current HEAD 670d6552eda8ff0c5f396d3d6f0174237917c66c testing commit 670d6552eda8ff0c5f396d3d6f0174237917c66c with gcc (GCC) 8.4.1 20210217 kernel signature: 60b79b68a08987db9d3ef445fab280361b5758be9fce656fc91f6157462b3c72 all runs: crashed: divide error in squashfs_readpage revisions tested: 2, total time: 21m2.885680645s (build: 14m28.85351545s, test: 6m12.287731825s) the crash still happens on HEAD commit msg: Linux 4.14.227 crash: divide error in squashfs_readpage batman_adv: batadv0: Interface activated: batadv_slave_0 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready IPv6: ADDRCONF(NETDEV_UP): veth1_virt_wifi: link is not ready IPv6: ADDRCONF(NETDEV_UP): veth1_macvtap: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): macvlan0: link becomes ready divide error: 0000 [#1] PREEMPT SMP KASAN IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready Modules linked in: CPU: 0 PID: 9049 Comm: syz-executor.0 Not tainted 4.14.227-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8881d2584140 task.stack: ffff8881ecad8000 RIP: 0010:fill_meta_index fs/squashfs/file.c:256 [inline] RIP: 0010:read_blocklist fs/squashfs/file.c:345 [inline] RIP: 0010:squashfs_readpage+0x7f4/0x21c0 fs/squashfs/file.c:482 RSP: 0018:ffff8881ecadf628 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881c7f284c8 RBP: ffff8881ecadf820 R08: ffffea00071e7810 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881c7f284c0 R13: 00000000000000de R14: 0000000000000099 R15: ffff8881c7f284f8 FS: 00007f57d3961700(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000055c071 CR3: 00000001ed403005 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 IPv6: ADDRCONF(NETDEV_CHANGE): macvlan0: link becomes ready DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready read_pages mm/readahead.c:131 [inline] __do_page_cache_readahead+0x679/0x950 mm/readahead.c:199 ra_submit mm/internal.h:66 [inline] ondemand_readahead+0x42b/0xbc0 mm/readahead.c:486 page_cache_sync_readahead mm/readahead.c:518 [inline] page_cache_sync_readahead+0x85/0xf0 mm/readahead.c:503 generic_file_buffered_read mm/filemap.c:2003 [inline] generic_file_read_iter+0xe53/0x1f30 mm/filemap.c:2273 call_read_iter include/linux/fs.h:1772 [inline] new_sync_read fs/read_write.c:401 [inline] __vfs_read+0x410/0x840 fs/read_write.c:413 vfs_read+0xff/0x310 fs/read_write.c:447 kernel_read+0x90/0x130 fs/read_write.c:426 prepare_binprm+0x5b5/0x800 fs/exec.c:1581 do_execveat_common.isra.14+0xd9e/0x1d70 fs/exec.c:1798 do_execveat fs/exec.c:1871 [inline] SYSC_execveat fs/exec.c:1952 [inline] SyS_execveat+0x46/0x60 fs/exec.c:1944 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x465889 RSP: 002b:00007f57d3961188 EFLAGS: 00000246 ORIG_RAX: 0000000000000142 RAX: ffffffffffffffda RBX: 000000000055bf00 RCX: 0000000000465889 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000005 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready RBP: 00000000004af68d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055bf00 R13: 00007ffddf86278f R14: 00007f57d3961300 R15: 0000000000022000 Code: 49 8b 47 c8 31 d2 48 63 8d 2c fe ff ff 48 89 85 90 fe ff ff 48 63 85 78 fe IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready ff ff 48 89 ce 48 c1 e1 0b c1 e6 0b 89 b5 60 fe ff ff <48> f7 f1 85 c0 48 89 85 68 IPv6: ADDRCONF(NETDEV_CHANGE): veth1_virt_wifi: link becomes ready fe ff ff 89 85 8c fe ff ff 0f 8e c3 RIP: fill_meta_index fs/squashfs/file.c:256 [inline] RSP: ffff8881ecadf628 RIP: read_blocklist fs/squashfs/file.c:345 [inline] RSP: ffff8881ecadf628 RIP: squashfs_readpage+0x7f4/0x21c0 fs/squashfs/file.c:482 RSP: ffff8881ecadf628 ---[ end trace ecb5d004f0cb3eed ]--- IPv6: ADDRCONF(NETDEV_CHANGE): veth0_virt_wifi: link becomes ready