assert "bp->b_data != NULL" failed in vfs_biomem.c (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4dba83b83de2 Add TCP Segmentation Offload (TSO) support fo..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=10024b2de80000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=ad7f0e0d846df4607d0b

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/374e799385cf/disk-4dba83b8.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/a752cdea5c25/bsd-4dba83b8.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/aa15eea0e3a4/kernel-4dba83b8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ad7f0e...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "bp->b_data != NULL" failed: file "/syzkaller/managers/main/kernel/sys/kern/vfs_biomem.c", line 235
Starting stack trace...
panic(ffffffff8278714d) at panic+0x159 sys/kern/subr_prf.c:229
__assert(ffffffff82802b97,ffffffff8281dd2b,eb,ffffffff8283dbd0) at __assert+0x29 sys/kern/subr_prf.c:157
buf_unmap(fffffd807e271270) at buf_unmap+0x1a8 sys/kern/vfs_biomem.c:235
buf_map(fffffd806d287dc0) at buf_map+0x1c7 sys/kern/vfs_biomem.c:117
buf_get(fffffd8064e8b100,c1,4000) at buf_get+0x763 sys/kern/vfs_bio.c:1189
getblk(fffffd8064e8b100,c1,4000,0,ffffffffffffffff) at getblk+0x10d sys/kern/vfs_bio.c:1057
bread_cluster(fffffd8064e8b100,c1,4000,ffff800030f10c80) at bread_cluster+0x59 bio_doread sys/kern/vfs_bio.c:433 [inline]
bread_cluster(fffffd8064e8b100,c1,4000,ffff800030f10c80) at bread_cluster+0x59 sys/kern/vfs_bio.c:596
ffs_read(ffff800030f10ce0) at ffs_read+0x343
VOP_READ(fffffd8064e8b100,ffff800030f10d70,0,fffffd807f7d7410) at VOP_READ+0xc3 sys/kern/vfs_vops.c:227
uvn_io(fffffd8067d91018,ffff800030f10e80,1,202,0) at uvn_io+0x39a
uvn_get(fffffd8067d91018,304000,ffff800030f10f48,ffff800030f10f18,0,3,57c647d916f0fcae,ffffffff81ce2c40) at uvn_get+0x1df sys/uvm/uvm_vnode.c:1110
uvm_fault_lower(ffff800030f110b0,ffff800030f110e8,ffff800030f11030,2) at uvm_fault_lower+0x88a sys/uvm/uvm_fault.c:1284
uvm_fault(fffffd8073ba08b8,1b2cd24000,2,3) at uvm_fault+0x20d
uvm_fault_wire(fffffd8073ba08b8,1b2ca60000,1b2ce20000,3) at uvm_fault_wire+0x63 sys/uvm/uvm_fault.c:1602
uvm_map_pageable_wire(fffffd8073ba08b8,fffffd8069c374c8,0,131,ffffffff81c22300,0) at uvm_map_pageable_wire+0x2cd sys/uvm/uvm_map.c:2190
sys_mlockall(ffff80002db69298,ffff800030f112f0,ffff800030f11340) at sys_mlockall+0x61 sys/uvm/uvm_mmap.c:896
syscall(ffff800030f113b0) at syscall+0x543 sys/arch/amd64/amd64/trap.c:606
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x147c2b72bd0, count: 239
End of stack trace.


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.