syzbot

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BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:646 [inline]
BUG: KASAN: slab-use-after-free in string+0x218/0x2b0 lib/vsprintf.c:728
Read of size 1 at addr ffff888020ec1560 by task udevd/5204

CPU: 1 UID: 0 PID: 5204 Comm: udevd Not tainted 6.12.0-next-20241128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 string_nocheck lib/vsprintf.c:646 [inline]
 string+0x218/0x2b0 lib/vsprintf.c:728
 vsnprintf+0x1101/0x1da0 lib/vsprintf.c:2848
 add_uevent_var+0x1c8/0x450 lib/kobject_uevent.c:679
 ib_device_uevent+0x79/0xa0 drivers/infiniband/core/device.c:519
 dev_uevent+0x4e4/0x900 drivers/base/core.c:2673
 uevent_show+0x1ba/0x340 drivers/base/core.c:2731
 dev_attr_show+0x55/0xc0 drivers/base/core.c:2423
 sysfs_kf_seq_show+0x331/0x4c0 fs/sysfs/file.c:59
 seq_read_iter+0x43f/0xd70 fs/seq_file.c:230
 new_sync_read fs/read_write.c:484 [inline]
 vfs_read+0x991/0xb70 fs/read_write.c:565
 ksys_read+0x18f/0x2b0 fs/read_write.c:708
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7fda916b6a
Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffe81eda6d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 000056079e2b19b0 RCX: 00007f7fda916b6a
RDX: 0000000000001000 RSI: 000056079e2af9f0 RDI: 000000000000000c
RBP: 000056079e2b19b0 R08: 000000000000000c R09: 0000000000000002
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000003fff R14: 00007ffe81edabb8 R15: 000000000000000a
 </TASK>

Allocated by task 7741:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4283 [inline]
 __kmalloc_node_track_caller_noprof+0x28b/0x4c0 mm/slub.c:4302
 __kmemdup_nul mm/util.c:61 [inline]
 kstrdup+0x39/0xb0 mm/util.c:81
 kobject_set_name_vargs+0x61/0x120 lib/kobject.c:274
 dev_set_name+0xd5/0x120 drivers/base/core.c:3468
 assign_name drivers/infiniband/core/device.c:1219 [inline]
 ib_register_device+0x178/0x13e0 drivers/infiniband/core/device.c:1401
 siw_device_register drivers/infiniband/sw/siw/siw_main.c:72 [inline]
 siw_newlink+0x9d9/0xe50 drivers/infiniband/sw/siw/siw_main.c:452
 nldev_newlink+0x5c0/0x640 drivers/infiniband/core/nldev.c:1795
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x6dd/0x9e0 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:726
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
 ___sys_sendmsg net/socket.c:2637 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 7741:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2338 [inline]
 slab_free mm/slub.c:4598 [inline]
 kfree+0x196/0x430 mm/slub.c:4746
 kobject_rename+0x38f/0x410 lib/kobject.c:524
 device_rename+0x16a/0x200 drivers/base/core.c:4570
 ib_device_rename+0x270/0x680 drivers/infiniband/core/device.c:419
 nldev_set_doit+0x2f2/0x480 drivers/infiniband/core/nldev.c:1146
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x6dd/0x9e0 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:726
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
 ___sys_sendmsg net/socket.c:2637 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888020ec1560
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 freed 8-byte region [ffff888020ec1560, ffff888020ec1568)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20ec1
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41500 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000800080 00000001f5000000 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 2779255619, free_ts 2778733938
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
 prep_new_page mm/page_alloc.c:1564 [inline]
 get_page_from_freelist+0x3738/0x3880 mm/page_alloc.c:3510
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4787
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x140 mm/slub.c:2408
 allocate_slab+0x5a/0x2f0 mm/slub.c:2574
 new_slab mm/slub.c:2627 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3815
 __slab_alloc+0x58/0xa0 mm/slub.c:3905
 __slab_alloc_node mm/slub.c:3980 [inline]
 slab_alloc_node mm/slub.c:4141 [inline]
 __do_kmalloc_node mm/slub.c:4282 [inline]
 __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4302
 __kmemdup_nul mm/util.c:61 [inline]
 kstrdup+0x39/0xb0 mm/util.c:81
 __kernfs_new_node+0x9d/0x870 fs/kernfs/dir.c:620
 kernfs_new_node+0x137/0x240 fs/kernfs/dir.c:700
 __kernfs_create_file+0x49/0x2e0 fs/kernfs/file.c:1034
 sysfs_add_bin_file_mode_ns+0x220/0x400 fs/sysfs/file.c:354
 sysfs_create_bin_file+0x1b4/0x2e0 fs/sysfs/file.c:595
 acpi_table_attr_init+0x4ee/0x700 drivers/acpi/sysfs.c:379
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xdef/0x1130 mm/page_alloc.c:2693
 __kmem_cache_do_shrink+0x344/0x3b0 mm/slub.c:5876
 acpi_os_purge_cache+0x15/0x20 drivers/acpi/osl.c:1585
 acpi_purge_cached_objects+0xb8/0xc0 drivers/acpi/acpica/utxface.c:240
 acpi_initialize_objects+0x2e/0xa0 drivers/acpi/acpica/utxfinit.c:250
 acpi_bus_init+0xda/0xbc0 drivers/acpi/bus.c:1367
 acpi_init+0xb4/0x240 drivers/acpi/bus.c:1454
 do_one_initcall+0x248/0x870 init/main.c:1266
 do_initcall_level+0x157/0x210 init/main.c:1328
 do_initcalls+0x3f/0x80 init/main.c:1344
 kernel_init_freeable+0x435/0x5d0 init/main.c:1577
 kernel_init+0x1d/0x2b0 init/main.c:1466
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff888020ec1400: fa fc fc fc 06 fc fc fc 05 fc fc fc 05 fc fc fc
 ffff888020ec1480: 05 fc fc fc 00 fc fc fc 00 fc fc fc fa fc fc fc
>ffff888020ec1500: 05 fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
                                                       ^
 ffff888020ec1580: fa fc fc fc 05 fc fc fc 06 fc fc fc 05 fc fc fc
 ffff888020ec1600: fa fc fc fc 05 fc fc fc 04 fc fc fc 04 fc fc fc
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