Subject: [syzbot] [wireguard?] [jfs?] KASAN: slab-use-after-free Read in wg_noise_keypair_get

From: syzbot <[email-masked]>
Date: Tue, 18 Jul 2023 08:21:13 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    51f269a6ecc7 Merge tag 'probes-fixes-6.4-rc4' of git://git..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=111705d1280000
kernel config:  https://syzkaller.appspot.com/x/.config?x=162cf2103e4a7453
dashboard link: https://syzkaller.appspot.com/bug?extid=96eb4e0d727f0ae998a6
compiler:       Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13101715280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dc3a22741e4e/disk-51f269a6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/61d77fe6cfb4/vmlinux-51f269a6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/bebce35b62e9/bzImage-51f269a6.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/d2ff4ad2d0c2/mount_0.gz

The issue was bisected to:

commit 586fb2641371cf7f23a401ab1c79b17e3ec457f4
Author: Kuninori Morimoto <[email-masked]>
Date:   Wed Jun 22 05:54:06 2022 +0000

    ASoC: soc-core.c: fixup snd_soc_of_get_dai_link_cpus()

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=108780b5280000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=128780b5280000
console output: https://syzkaller.appspot.com/x/log.txt?x=148780b5280000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]
Fixes: 586fb2641371 ("ASoC: soc-core.c: fixup snd_soc_of_get_dai_link_cpus()")

IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: slab-use-after-free in refcount_read include/linux/refcount.h:147 [inline]
BUG: KASAN: slab-use-after-free in __refcount_add_not_zero include/linux/refcount.h:152 [inline]
BUG: KASAN: slab-use-after-free in __refcount_inc_not_zero include/linux/refcount.h:227 [inline]
BUG: KASAN: slab-use-after-free in refcount_inc_not_zero include/linux/refcount.h:245 [inline]
BUG: KASAN: slab-use-after-free in kref_get_unless_zero include/linux/kref.h:111 [inline]
BUG: KASAN: slab-use-after-free in wg_noise_keypair_get+0xd2/0x3a0 drivers/net/wireguard/noise.c:146
Read of size 4 at addr ffff88807d0304d8 by task kworker/0:6/5139

CPU: 0 PID: 5139 Comm: kworker/0:6 Not tainted 6.4.0-rc4-syzkaller-00268-g51f269a6ecc7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:351 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:462
 kasan_report+0x176/0x1b0 mm/kasan/report.c:572
 kasan_check_range+0x283/0x290 mm/kasan/generic.c:187
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 refcount_read include/linux/refcount.h:147 [inline]
 __refcount_add_not_zero include/linux/refcount.h:152 [inline]
 __refcount_inc_not_zero include/linux/refcount.h:227 [inline]
 refcount_inc_not_zero include/linux/refcount.h:245 [inline]
 kref_get_unless_zero include/linux/kref.h:111 [inline]
 wg_noise_keypair_get+0xd2/0x3a0 drivers/net/wireguard/noise.c:146
 wg_packet_send_staged_packets+0x406/0x1890 drivers/net/wireguard/send.c:357
 wg_xmit+0xbca/0x1120 drivers/net/wireguard/device.c:217
 __netdev_start_xmit include/linux/netdevice.h:4915 [inline]
 netdev_start_xmit include/linux/netdevice.h:4929 [inline]
 xmit_one net/core/dev.c:3578 [inline]
 dev_hard_start_xmit+0x241/0x750 net/core/dev.c:3594
 __dev_queue_xmit+0x19b9/0x38b0 net/core/dev.c:4244
 neigh_output include/net/neighbour.h:544 [inline]
 ip6_finish_output2+0xf80/0x1560 net/ipv6/ip6_output.c:134
 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
 ip6_finish_output+0x6b0/0xa80 net/ipv6/ip6_output.c:206
 dst_output include/net/dst.h:458 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 ndisc_send_skb+0xb08/0x1390 net/ipv6/ndisc.c:508
 addrconf_dad_completed+0x6ea/0xcf0 net/ipv6/addrconf.c:4254
 addrconf_dad_work+0xd92/0x16b0
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2405
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2552
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Allocated by task 5137:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 keypair_create drivers/net/wireguard/noise.c:100 [inline]
 wg_noise_handshake_begin_session+0xc4/0xb60 drivers/net/wireguard/noise.c:827
 wg_packet_send_handshake_response+0x120/0x2d0 drivers/net/wireguard/send.c:96
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:154 [inline]
 wg_packet_handshake_receive_worker+0x5dd/0xf00 drivers/net/wireguard/receive.c:213
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2405
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2552
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Freed by task 5086:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:162 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook mm/slub.c:1807 [inline]
 slab_free mm/slub.c:3786 [inline]
 __kmem_cache_free+0x264/0x3c0 mm/slub.c:3799
 diUnmount+0xf3/0x100 fs/jfs/jfs_imap.c:195
 jfs_umount+0x186/0x3a0 fs/jfs/jfs_umount.c:63
 jfs_put_super+0x8a/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x134/0x340 fs/super.c:500
 kill_block_super+0x84/0xf0 fs/super.c:1407
 deactivate_locked_super+0xa4/0x110 fs/super.c:331
 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1177
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88807d030000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1240 bytes inside of
 freed 2048-byte region [ffff88807d030000, ffff88807d030800)

The buggy address belongs to the physical page:
page:ffffea0001f40c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d030
head:ffffea0001f40c00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000010200 ffff888012442000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5137, tgid 5137 (kworker/1:5), ts 1071863956331, free_ts 1071845351658
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3502
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4768
 alloc_slab_page+0x6a/0x160 mm/slub.c:1851
 allocate_slab mm/slub.c:1998 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2051
 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192
 __slab_alloc mm/slub.c:3291 [inline]
 __slab_alloc_node mm/slub.c:3344 [inline]
 slab_alloc_node mm/slub.c:3441 [inline]
 __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490
 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1057
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 keypair_create drivers/net/wireguard/noise.c:100 [inline]
 wg_noise_handshake_begin_session+0xc4/0xb60 drivers/net/wireguard/noise.c:827
 wg_packet_send_handshake_response+0x120/0x2d0 drivers/net/wireguard/send.c:96
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:154 [inline]
 wg_packet_handshake_receive_worker+0x5dd/0xf00 drivers/net/wireguard/receive.c:213
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2405
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2552
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1302 [inline]
 free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2564
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2659
 free_large_kmalloc+0xff/0x190 mm/slab_common.c:943
 diMount+0x657/0x870 fs/jfs/jfs_imap.c:115
 jfs_mount_rw+0x2da/0x6a0 fs/jfs/jfs_mount.c:240
 jfs_remount+0x3d1/0x6b0 fs/jfs/super.c:454
 reconfigure_super+0x3c9/0x7c0 fs/super.c:956
 vfs_fsconfig_locked fs/fsopen.c:254 [inline]
 __do_sys_fsconfig fs/fsopen.c:439 [inline]
 __se_sys_fsconfig+0xa29/0xf70 fs/fsopen.c:314
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff88807d030380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d030400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807d030480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88807d030500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d030580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

---
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