From: syzbot <syzbot+b01a29c8051dcb87f37d@syzkaller.appspotmail.com>
To: hch@lst.de, justin.tee@broadcom.com, kch@nvidia.com,
linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
nareshgottumukkala83@gmail.com, paul.ely@broadcom.com,
sagi@grimberg.me, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [nvme?] KASAN: invalid-free in nvmet_fc_alloc_ls_iodlist
Date: Sun, 09 Aug 2026 17:23:27 -0700 [thread overview]
Message-ID: <6a7919ff.9c11d2ce.289b96.00e0.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 848acc8ffe1b Merge tag 'fsverity-for-linus' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16b813b9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c05be6c9b0d36cb9
dashboard link: https://syzkaller.appspot.com/bug?extid=b01a29c8051dcb87f37d
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-848acc8f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2425c07b5d46/vmlinux-848acc8f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cf278dd14da3/bzImage-848acc8f.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b01a29c8051dcb87f37d@syzkaller.appspotmail.com
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
CPU: 0 UID: 0 PID: 5325 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 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
fail_dump lib/fault-inject.c:73 [inline]
should_fail_ex+0x40c/0x560 lib/fault-inject.c:174
should_failslab+0xa8/0x100 mm/failslab.c:46
slab_pre_alloc_hook mm/slub.c:4539 [inline]
slab_alloc_node mm/slub.c:4897 [inline]
__kmalloc_cache_noprof+0xa8/0x660 mm/slub.c:5485
_kmalloc_noprof include/linux/slab.h:988 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
nvmet_fc_alloc_ls_iodlist+0x334/0x940 drivers/nvme/target/fc.c:542
nvmet_fc_register_targetport+0x76a/0x9e0 drivers/nvme/target/fc.c:1411
fcloop_create_target_port+0x135/0x4c0 drivers/nvme/target/fcloop.c:1558
kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad8719e019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fad88044fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fad87425fa0 RCX: 00007fad8719e019
RDX: 000000000000002f RSI: 0000200000000400 RDI: 0000000000000003
RBP: 00007fad88045050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fad87426038 R14: 00007fad87425fa0 R15: 00007ffee36393b8
</TASK>
==================================================================
BUG: KASAN: invalid-free in nvmet_fc_alloc_ls_iodlist+0x915/0x940 drivers/nvme/target/fc.c:569
Free of addr ffff8880136fff20 by task syz.0.0/5325
CPU: 0 UID: 0 PID: 5325 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 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report_invalid_free+0xea/0x110 mm/kasan/report.c:557
check_slab_allocation mm/kasan/common.c:-1 [inline]
__kasan_slab_pre_free+0x104/0x120 mm/kasan/common.c:261
kasan_slab_pre_free include/linux/kasan.h:199 [inline]
slab_free_hook mm/slub.c:2622 [inline]
slab_free mm/slub.c:6377 [inline]
kfree+0x173/0x640 mm/slub.c:6692
nvmet_fc_alloc_ls_iodlist+0x915/0x940 drivers/nvme/target/fc.c:569
nvmet_fc_register_targetport+0x76a/0x9e0 drivers/nvme/target/fc.c:1411
fcloop_create_target_port+0x135/0x4c0 drivers/nvme/target/fcloop.c:1558
kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad8719e019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fad88044fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fad87425fa0 RCX: 00007fad8719e019
RDX: 000000000000002f RSI: 0000200000000400 RDI: 0000000000000003
RBP: 00007fad88045050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fad87426038 R14: 00007fad87425fa0 R15: 00007ffee36393b8
</TASK>
Allocated by task 12:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5334 [inline]
__kmalloc_noprof+0x375/0x720 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
neigh_alloc net/core/neighbour.c:518 [inline]
___neigh_create+0x6d2/0x22b0 net/core/neighbour.c:652
ip6_finish_output2+0x6d6/0x13c0 net/ipv6/ip6_output.c:128
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x292/0x770 net/ipv6/ip6_output.c:219
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip6_output+0x337/0x540 net/ipv6/ip6_output.c:246
dst_output include/net/dst.h:471 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
ndisc_send_skb+0xcb2/0x1650 net/ipv6/ndisc.c:512
ndisc_send_ns+0xd7/0x160 net/ipv6/ndisc.c:671
addrconf_dad_work+0xa8d/0x15c0 net/ipv6/addrconf.c:4317
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
The buggy address belongs to the object at ffff8880136ff800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 992 bytes to the right of
832-byte region [ffff8880136ff800, ffff8880136ffb40)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x136fc
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b041dc0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b041dc0 dead000000000100 dead000000000122
head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 12, tgid 12 (kworker/u4:0), ts 93793846953, free_ts 92088318708
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3266 [inline]
allocate_slab+0x79/0x5e0 mm/slub.c:3380
new_slab mm/slub.c:3426 [inline]
refill_objects+0x2d5/0x350 mm/slub.c:7310
refill_sheaf mm/slub.c:2804 [inline]
__pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4675
alloc_from_pcs mm/slub.c:4773 [inline]
slab_alloc_node mm/slub.c:4905 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_noprof+0x485/0x720 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
neigh_alloc net/core/neighbour.c:518 [inline]
___neigh_create+0x6d2/0x22b0 net/core/neighbour.c:652
ip6_finish_output2+0x6d6/0x13c0 net/ipv6/ip6_output.c:128
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x292/0x770 net/ipv6/ip6_output.c:219
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip6_output+0x337/0x540 net/ipv6/ip6_output.c:246
dst_output include/net/dst.h:471 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
ndisc_send_skb+0xcb2/0x1650 net/ipv6/ndisc.c:512
ndisc_send_ns+0xd7/0x160 net/ipv6/ndisc.c:671
addrconf_dad_work+0xa8d/0x15c0 net/ipv6/addrconf.c:4317
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
page last free pid 15 tgid 15 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950
rcu_do_batch kernel/rcu/tree.c:2645 [inline]
rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897
handle_softirqs+0x225/0x840 kernel/softirq.c:622
run_ksoftirqd+0x36/0x60 kernel/softirq.c:1076
smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffff8880136ffe00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880136ffe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880136fff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8880136fff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888013700000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
---
This report is generated by a bot. It may contain errors.
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reply other threads:[~2026-08-10 0:23 UTC|newest]
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