bisecting fixing commit since f2d285669aae656dfeafa0bf25e86bbbc5d22329
building syzkaller on 676bd07e7e80f8a270af7f0276443c68f4a99e25
testing commit f2d285669aae656dfeafa0bf25e86bbbc5d22329 with gcc (GCC) 8.1.0
kernel signature: f1dc57947f7cc4a77093c39c6253c88d08cd0c8111e431b27cf1c0ace5af591a
all runs: crashed: WARNING in hfs_bnode_create
testing current HEAD 3be20b6fc13abff843901fcd7cd9c7a3a7f95b90
testing commit 3be20b6fc13abff843901fcd7cd9c7a3a7f95b90 with gcc (GCC) 8.1.0
kernel signature: 6c02b08915ae672cd960b7c6136f6cd20bd980d57f748ef61ad20f8610b14458
all runs: crashed: WARNING in hfs_bnode_create
revisions tested: 2, total time: 16m28.537238802s (build: 9m41.679580702s, test: 6m6.286459677s)
the crash still happens on HEAD
commit msg: Merge tag 'ext4-for-linus-5.8-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
crash: WARNING in hfs_bnode_create
hfs: unable to locate alternate MDB
hfs: continuing without an alternate MDB
hfs: new node 0 already hashed?
hfs: unable to locate alternate MDB
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3752 at fs/hfs/bnode.c:416 hfs_bnode_create.cold.15+0xe/0x15 fs/hfs/bnode.c:415
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 3752 Comm: syz-executor3 Not tainted 5.8.0-rc1-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+0x136/0x187 lib/dump_stack.c:118
 panic+0x22a/0x4f5 kernel/panic.c:231
 __warn.cold.12+0x25/0x25 kernel/panic.c:600
 report_bug+0x1b5/0x260 lib/bug.c:198
 exc_invalid_op+0x1be/0x370 arch/x86/kernel/traps.c:235
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:563
RIP: 0010:hfs_bnode_create.cold.15+0xe/0x15 fs/hfs/bnode.c:416
Code: db e8 ba fd 54 ff e9 14 e0 ff ff 48 c7 c7 60 40 7b 87 e8 a9 fd 54 ff e9 9f f6 ff ff 89 de 48 c7 c7 a0 40 7b 87 e8 96 fd 54 ff <0f> 0b e9 de fe ff ff 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41
RSP: 0018:ffff8881c8da7898 EFLAGS: 00010282
RAX: 000000000000001f RBX: 0000000000000000 RCX: ffffffff82e3aaae
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8881db0281ac
RBP: ffff8881c8da78e0 R08: ffffed103b606325 R09: ffffed103b606325
R10: ffff8881db031927 R11: ffffed103b606324 R12: ffff8881c86ae0e0
R13: dffffc0000000000 R14: ffff8881d113ed00 R15: ffff8881d113ed00
 hfs_bmap_alloc+0x42f/0x5e0 fs/hfs/btree.c:288
 hfs_bnode_split+0xbd/0xe20 fs/hfs/brec.c:241
 hfs_brec_insert+0x2f0/0xbb0 fs/hfs/brec.c:102
 hfs_cat_create+0x6ae/0x8a0 fs/hfs/catalog.c:131
 hfs_mkdir+0x57/0xc0 fs/hfs/dir.c:231
 vfs_mkdir+0x384/0x610 fs/namei.c:3641
 do_mkdirat+0x1b7/0x210 fs/namei.c:3664
 __do_sys_mkdir fs/namei.c:3680 [inline]
 __se_sys_mkdir fs/namei.c:3678 [inline]
 __x64_sys_mkdir+0x57/0x80 fs/namei.c:3678
 do_syscall_64+0x6e/0xf0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455429
Code: Bad RIP value.
RSP: 002b:00007f1137cf7c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f1137cf86d4 RCX: 0000000000455429
RDX: 0000000000000000 RSI: 0000000000000021 RDI: 0000000020000180
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000003ea R14: 00000000006f8e90 R15: 0000000000000000
Kernel Offset: disabled