Subject: [syzbot] [net?] KASAN: slab-use-after-free Read in tls_encrypt_done

From: syzbot <[email-masked]>
Date: Fri, 29 Sep 2023 11:43:35 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    6465e260f487 Linux 6.6-rc3
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=114f1f96680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8d7d7928f78936aa
dashboard link: https://syzkaller.appspot.com/bug?extid=29c22ea2d6b2c5fd2eae
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15c6888e680000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=174c3996680000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-6465e260.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3560b94cfbc8/vmlinux-6465e260.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a098d6f44df3/bzImage-6465e260.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

==================================================================
BUG: KASAN: slab-use-after-free in debug_spin_unlock kernel/locking/spinlock_debug.c:99 [inline]
BUG: KASAN: slab-use-after-free in do_raw_spin_unlock+0x1f7/0x230 kernel/locking/spinlock_debug.c:140
Read of size 4 at addr ffff88801f5a7d3c by task kworker/2:1/36

CPU: 2 PID: 36 Comm: kworker/2:1 Not tainted 6.6.0-rc3-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: pencrypt_serial padata_serial_worker
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:475
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 debug_spin_unlock kernel/locking/spinlock_debug.c:99 [inline]
 do_raw_spin_unlock+0x1f7/0x230 kernel/locking/spinlock_debug.c:140
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:166 [inline]
 _raw_spin_unlock_bh+0x1e/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 tls_encrypt_done+0x281/0x560 net/tls/tls_sw.c:488
 padata_serial_worker+0x246/0x490 kernel/padata.c:378
 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>

Allocated by task 19233:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:599 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 tls_set_sw_offload+0x12e0/0x1700 net/tls/tls_sw.c:2606
 do_tls_setsockopt_conf net/tls/tls_main.c:667 [inline]
 do_tls_setsockopt net/tls/tls_main.c:772 [inline]
 tls_setsockopt+0x108c/0x1340 net/tls/tls_main.c:800
 __sys_setsockopt+0x2cd/0x5b0 net/socket.c:2308
 __do_sys_setsockopt net/socket.c:2319 [inline]
 __se_sys_setsockopt net/socket.c:2316 [inline]
 __x64_sys_setsockopt+0xbd/0x150 net/socket.c:2316
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 19233:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x138/0x190 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:164 [inline]
 __cache_free mm/slab.c:3370 [inline]
 __do_kmem_cache_free mm/slab.c:3557 [inline]
 __kmem_cache_free+0xcc/0x2d0 mm/slab.c:3564
 tls_sk_proto_close+0x4c3/0xb00 net/tls/tls_main.c:390
 inet_release+0x132/0x270 net/ipv4/af_inet.c:433
 inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:484
 __sock_release+0xae/0x260 net/socket.c:659
 sock_close+0x1c/0x20 net/socket.c:1402
 __fput+0x3f7/0xa70 fs/file_table.c:384
 task_work_run+0x14d/0x240 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa92/0x2a20 kernel/exit.c:874
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
 __do_sys_exit_group kernel/exit.c:1035 [inline]
 __se_sys_exit_group kernel/exit.c:1033 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Last potentially related work creation:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0x78/0x80 mm/kasan/generic.c:492
 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3372
 tls_ctx_free net/tls/tls_main.c:333 [inline]
 tls_ctx_free+0x69/0x90 net/tls/tls_main.c:323
 tls_sk_proto_close+0x46b/0xb00 net/tls/tls_main.c:398
 inet_release+0x132/0x270 net/ipv4/af_inet.c:433
 inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:484
 __sock_release+0xae/0x260 net/socket.c:659
 sock_close+0x1c/0x20 net/socket.c:1402
 __fput+0x3f7/0xa70 fs/file_table.c:384
 task_work_run+0x14d/0x240 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa92/0x2a20 kernel/exit.c:874
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
 __do_sys_exit_group kernel/exit.c:1035 [inline]
 __se_sys_exit_group kernel/exit.c:1033 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Second to last potentially related work creation:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0x78/0x80 mm/kasan/generic.c:492
 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3372
 tls_ctx_free net/tls/tls_main.c:333 [inline]
 tls_ctx_free+0x69/0x90 net/tls/tls_main.c:323
 tls_sk_proto_close+0x46b/0xb00 net/tls/tls_main.c:398
 inet_release+0x132/0x270 net/ipv4/af_inet.c:433
 inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:484
 __sock_release+0xae/0x260 net/socket.c:659
 sock_close+0x1c/0x20 net/socket.c:1402
 __fput+0x3f7/0xa70 fs/file_table.c:384
 task_work_run+0x14d/0x240 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa92/0x2a20 kernel/exit.c:874
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
 __do_sys_exit_group kernel/exit.c:1035 [inline]
 __se_sys_exit_group kernel/exit.c:1033 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88801f5a7c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 316 bytes inside of
 freed 512-byte region [ffff88801f5a7c00, ffff88801f5a7e00)

The buggy address belongs to the physical page:
page:ffffea00007d69c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f5a7
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0x4()
raw: 00fff00000000800 ffff888012c40600 ffffea000076b490 ffffea00006bae50
raw: 0000000000000000 ffff88801f5a7000 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x242020(__GFP_HIGH|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 6562, tgid 6562 (syz-executor469), ts 291264206650, free_ts 291263177339
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536
 prep_new_page mm/page_alloc.c:1543 [inline]
 get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170
 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 kmem_getpages mm/slab.c:1356 [inline]
 cache_grow_begin+0x99/0x3a0 mm/slab.c:2550
 cache_alloc_refill+0x294/0x3a0 mm/slab.c:2923
 ____cache_alloc mm/slab.c:2999 [inline]
 ____cache_alloc mm/slab.c:2982 [inline]
 __do_cache_alloc mm/slab.c:3182 [inline]
 slab_alloc_node mm/slab.c:3230 [inline]
 __kmem_cache_alloc_node+0x3c5/0x470 mm/slab.c:3521
 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1114
 kmalloc include/linux/slab.h:599 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 tls_ctx_create+0x45/0x140 net/tls/tls_main.c:808
 tls_init net/tls/tls_main.c:951 [inline]
 tls_init+0x11e/0xbc0 net/tls/tls_main.c:928
 __tcp_set_ulp net/ipv4/tcp_ulp.c:146 [inline]
 tcp_set_ulp+0x31f/0x7e0 net/ipv4/tcp_ulp.c:167
 do_tcp_setsockopt+0x5cb/0x2830 net/ipv4/tcp.c:3429
 tcp_setsockopt+0xd4/0x100 net/ipv4/tcp.c:3679
 __sys_setsockopt+0x2cd/0x5b0 net/socket.c:2308
 __do_sys_setsockopt net/socket.c:2319 [inline]
 __se_sys_setsockopt net/socket.c:2316 [inline]
 __x64_sys_setsockopt+0xbd/0x150 net/socket.c:2316
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1136 [inline]
 free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312
 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405
 __folio_put_small mm/swap.c:106 [inline]
 __folio_put+0xc3/0x110 mm/swap.c:129
 folio_put include/linux/mm.h:1475 [inline]
 put_page include/linux/mm.h:1544 [inline]
 free_page_and_swap_cache+0x25a/0x2d0 mm/swap_state.c:303
 __tlb_remove_table arch/x86/include/asm/tlb.h:34 [inline]
 __tlb_remove_table_free mm/mmu_gather.c:154 [inline]
 tlb_remove_table_rcu+0x89/0xe0 mm/mmu_gather.c:209
 rcu_do_batch kernel/rcu/tree.c:2139 [inline]
 rcu_core+0x805/0x1bb0 kernel/rcu/tree.c:2403
 __do_softirq+0x218/0x965 kernel/softirq.c:553

Memory state around the buggy address:
 ffff88801f5a7c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801f5a7c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801f5a7d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88801f5a7d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801f5a7e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

---
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