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UBSAN: array-index-out-of-bounds in fs/ocfs2/alloc.c:1090:9
index -1 is out of range for type 'struct ocfs2_extent_rec[] __counted_by(l_count)' (aka 'struct ocfs2_extent_rec[]')
CPU: 0 UID: 0 PID: 5341 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
 __ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:455
 ocfs2_sum_rightmost_rec fs/ocfs2/alloc.c:1090 [inline]
 ocfs2_shift_tree_depth fs/ocfs2/alloc.c:1412 [inline]
 ocfs2_grow_tree+0x35af/0x3dc0 fs/ocfs2/alloc.c:1560
 ocfs2_insert_extent+0xb54/0x15a0 fs/ocfs2/alloc.c:4755
 ocfs2_add_clusters_in_btree+0x64f/0xf50 fs/ocfs2/alloc.c:4857
 ocfs2_add_inode_data+0xce/0x120 fs/ocfs2/file.c:550
 ocfs2_write_cluster fs/ocfs2/aops.c:1115 [inline]
 ocfs2_write_cluster_by_desc+0x547/0x1cf0 fs/ocfs2/aops.c:1219
 ocfs2_write_begin_nolock+0x3180/0x4300 fs/ocfs2/aops.c:1796
 ocfs2_write_begin+0x1bb/0x310 fs/ocfs2/aops.c:1884
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
 ocfs2_file_write_iter+0x1582/0x1cf0 fs/ocfs2/file.c:2469
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefe178f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefe2622038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fefe19e6090 RCX: 00007fefe178f7c9
RDX: 0000000000000140 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007fefe1813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefe19e6128 R14: 00007fefe19e6090 R15: 00007ffd3b9bba38
 </TASK>
---[ end trace ]---