From: syzbot <syzbot+4334f9a250019c1b79b4@syzkaller.appspotmail.com>
To: jgg@ziepe.ca, leon@kernel.org, linux-kernel@vger.kernel.org,
linux-rdma@vger.kernel.org, syzkaller-bugs@googlegroups.com,
tahernady45@gmail.com
Subject: Re: [syzbot] [rdma?] KFENCE: invalid free in gid_table_release_one
Date: Tue, 31 Mar 2026 14:00:28 -0700 [thread overview]
Message-ID: <69cc35ec.a70a0220.97f31.02a2.GAE@google.com> (raw)
In-Reply-To: <69cc20ce.050a0220.183828.0033.GAE@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: 36ece9697e89 Add linux-next specific files for 20260331
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=10dc99f6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e5c508e55e8ef9a7
dashboard link: https://syzkaller.appspot.com/bug?extid=4334f9a250019c1b79b4
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15ebf5da580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1253b3d6580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/46de62fad824/disk-36ece969.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/88dd71e1e51a/vmlinux-36ece969.xz
kernel image: https://storage.googleapis.com/syzbot-assets/51e7e482e157/bzImage-36ece969.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4334f9a250019c1b79b4@syzkaller.appspotmail.com
smbdirect: ib_dev[syz2] removed
==================================================================
BUG: KASAN: invalid-free in release_gid_table drivers/infiniband/core/cache.c:804 [inline]
BUG: KASAN: invalid-free in gid_table_release_one+0x384/0x470 drivers/infiniband/core/cache.c:877
Free of addr ffff88802bcdb6d8 by task kworker/u8:2/35
CPU: 1 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: ib-unreg-wq ib_unregister_work
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:2634 [inline]
slab_free mm/slub.c:6242 [inline]
kfree+0x173/0x640 mm/slub.c:6557
release_gid_table drivers/infiniband/core/cache.c:804 [inline]
gid_table_release_one+0x384/0x470 drivers/infiniband/core/cache.c:877
ib_device_release+0xd2/0x1c0 drivers/infiniband/core/device.c:482
device_release+0xc4/0x1f0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x228/0x560 lib/kobject.c:737
process_one_work kernel/workqueue.c:3278 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3361
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3442
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
</TASK>
Allocated by task 6021:
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:5292 [inline]
__kmalloc_noprof+0x35c/0x760 mm/slub.c:5304
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
alloc_gid_table drivers/infiniband/core/cache.c:773 [inline]
_gid_table_setup_one drivers/infiniband/core/cache.c:888 [inline]
gid_table_setup_one drivers/infiniband/core/cache.c:916 [inline]
ib_cache_setup_one+0x198/0x570 drivers/infiniband/core/cache.c:1606
ib_register_device+0xfbd/0x13e0 drivers/infiniband/core/device.c:1426
siw_device_register drivers/infiniband/sw/siw/siw_main.c:71 [inline]
siw_newlink+0x8fe/0xde0 drivers/infiniband/sw/siw/siw_main.c:430
nldev_newlink+0x5bc/0x650 drivers/infiniband/core/nldev.c:1812
rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0x6d1/0xa10 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:786 [inline]
__sock_sendmsg net/socket.c:801 [inline]
____sys_sendmsg+0x972/0x9f0 net/socket.c:2650
___sys_sendmsg+0x2a5/0x360 net/socket.c:2704
__sys_sendmsg net/socket.c:2736 [inline]
__do_sys_sendmsg net/socket.c:2741 [inline]
__se_sys_sendmsg net/socket.c:2739 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88802bcdb600
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 216 bytes inside of
224-byte region [ffff88802bcdb600, ffff88802bcdb6e0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bcda
head: order:1 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 ffff88813fe38b40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fe38b40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5953, tgid 5953 (syz-executor), ts 101457682506, free_ts 101330013904
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x24ba/0x2540 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
alloc_slab_page mm/slub.c:3278 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3467
new_slab mm/slub.c:3525 [inline]
refill_objects+0x339/0x3d0 mm/slub.c:7247
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x321/0x720 mm/slub.c:4651
alloc_from_pcs mm/slub.c:4749 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__kmalloc_cache_noprof+0x392/0x660 mm/slub.c:5407
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
____ip_mc_inc_group+0x518/0xdd0 net/ipv4/igmp.c:1535
__ip_mc_inc_group net/ipv4/igmp.c:1573 [inline]
ip_mc_inc_group net/ipv4/igmp.c:1579 [inline]
ip_mc_up+0x115/0x2e0 net/ipv4/igmp.c:1880
inetdev_event+0xff6/0x1610 net/ipv4/devinet.c:1630
notifier_call_chain+0x1ad/0x3d0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2285 [inline]
call_netdevice_notifiers net/core/dev.c:2299 [inline]
__dev_notify_flags+0x1a9/0x310 net/core/dev.c:9835
netif_change_flags+0xe8/0x1a0 net/core/dev.c:9864
do_setlink+0xf82/0x4590 net/core/rtnetlink.c:3180
rtnl_changelink net/core/rtnetlink.c:3798 [inline]
__rtnl_newlink net/core/rtnetlink.c:3957 [inline]
rtnl_newlink+0x15a9/0x1be0 net/core/rtnetlink.c:4094
rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6980
page last free pid 5953 tgid 5953 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
rcu_do_batch kernel/rcu/tree.c:2617 [inline]
rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869
handle_softirqs+0x22a/0x840 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
Memory state around the buggy address:
ffff88802bcdb580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802bcdb600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88802bcdb680: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
^
ffff88802bcdb700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802bcdb780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
next prev parent reply other threads:[~2026-03-31 21:00 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-31 19:30 [syzbot] [rdma?] KFENCE: invalid free in gid_table_release_one syzbot
2026-03-31 21:00 ` syzbot [this message]
2026-04-01 1:00 ` Forwarded: [PATCH] RDMA/cache: fix invalid-free of flex-array data_vec in release_gid_table syzbot
[not found] <20260401010030.10174-1-kartikey406@gmail.com>
2026-04-01 1:25 ` [syzbot] [rdma?] KFENCE: invalid free in gid_table_release_one syzbot
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