syzbot

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BUG: KASAN: use-after-free in bq_enqueue kernel/bpf/cpumap.c:749 [inline]
BUG: KASAN: use-after-free in cpu_map_enqueue+0xb6/0x370 kernel/bpf/cpumap.c:775
Read of size 8 at addr ffff8880273c8e08 by task syz.3.38/4492

CPU: 1 PID: 4492 Comm: syz.3.38 Not tainted 6.1.126-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:427
 kasan_report+0x136/0x160 mm/kasan/report.c:531
 bq_enqueue kernel/bpf/cpumap.c:749 [inline]
 cpu_map_enqueue+0xb6/0x370 kernel/bpf/cpumap.c:775
 __xdp_do_redirect_frame net/core/filter.c:4324 [inline]
 xdp_do_redirect_frame+0x2f0/0x660 net/core/filter.c:4382
 xdp_test_run_batch net/bpf/test_run.c:314 [inline]
 bpf_test_run_xdp_live+0xbf4/0x1ea0 net/bpf/test_run.c:362
 bpf_prog_test_run_xdp+0x7d1/0x1130 net/bpf/test_run.c:1393
 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3690
 __sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5043
 __do_sys_bpf kernel/bpf/syscall.c:5129 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5127 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5127
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f42c1185d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f42c1f15038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f42c1375fa0 RCX: 00007f42c1185d29
RDX: 0000000000000050 RSI: 00000000200000c0 RDI: 000000000000000a
RBP: 00007f42c1201b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f42c1375fa0 R15: 00007ffcc8e90538
 </TASK>

Allocated by task 4486:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:936 [inline]
 __kmalloc_node+0xb3/0x230 mm/slab_common.c:943
 kmalloc_node include/linux/slab.h:589 [inline]
 bpf_map_kmalloc_node+0xce/0x1c0 kernel/bpf/syscall.c:452
 __cpu_map_entry_alloc kernel/bpf/cpumap.c:445 [inline]
 cpu_map_update_elem+0x277/0xf60 kernel/bpf/cpumap.c:603
 map_update_elem+0x503/0x680 kernel/bpf/syscall.c:1463
 __sys_bpf+0x337/0x6c0 kernel/bpf/syscall.c:5013
 __do_sys_bpf kernel/bpf/syscall.c:5129 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5127 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5127
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 4487:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 put_cpu_map_entry+0x6eb/0x760 kernel/bpf/cpumap.c:161
 cpu_map_kthread_run+0x2887/0x2940 kernel/bpf/cpumap.c:408
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 insert_work+0x54/0x3d0 kernel/workqueue.c:1361
 __queue_work+0xb4b/0xf90 kernel/workqueue.c:1520
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1548
 cpu_map_free+0xd7/0x1b0 kernel/bpf/cpumap.c:641
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845
 __cpu_map_entry_replace+0x74/0x170 kernel/bpf/cpumap.c:556
 cpu_map_free+0xd7/0x1b0 kernel/bpf/cpumap.c:641
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff8880273c8e00
 which belongs to the cache kmalloc-cg-256 of size 256
The buggy address is located 8 bytes inside of
 256-byte region [ffff8880273c8e00, ffff8880273c8f00)

The buggy address belongs to the physical page:
page:ffffea00009cf200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x273c8
head:ffffea00009cf200 order:1 compound_mapcount:0 compound_pincount:0
memcg:ffff88805de73f01
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888017c42c80
raw: 0000000000000000 0000000080100010 00000001ffffffff ffff88805de73f01
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4355, tgid 4355 (syz-executor), ts 80795292220, free_ts 80674538815
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4328
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5605
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa1/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 fib_default_rule_add+0x4a/0x3a0 net/core/fib_rules.c:60
 fib6_rules_net_init+0x6a/0x100 net/ipv6/fib6_rules.c:492
 ops_init+0x35d/0x610 net/core/net_namespace.c:138
 setup_net+0x4b5/0xb90 net/core/net_namespace.c:335
 copy_net_ns+0x352/0x590 net/core/net_namespace.c:498
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x531/0xa40 kernel/fork.c:3201
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x12a6/0x15b0 mm/page_alloc.c:3384
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3479
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x137/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa1/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26b/0x530 security/tomoyo/realpath.c:80
 tomoyo_mount_acl security/tomoyo/mount.c:150 [inline]
 tomoyo_mount_permission+0x534/0xb60 security/tomoyo/mount.c:237
 security_sb_mount+0x88/0xc0 security/security.c:993
 path_mount+0xbd/0x1090 fs/namespace.c:3328
 do_mount fs/namespace.c:3399 [inline]
 __do_sys_mount fs/namespace.c:3607 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff8880273c8d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880273c8d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880273c8e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8880273c8e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880273c8f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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