==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:653 [inline]
BUG: KASAN: slab-use-after-free in string+0x231/0x2b0 lib/vsprintf.c:735
Read of size 1 at addr ffff88805657e820 by task udevd/5230

CPU: 1 UID: 0 PID: 5230 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 string_nocheck lib/vsprintf.c:653 [inline]
 string+0x231/0x2b0 lib/vsprintf.c:735
 vsnprintf+0x739/0xf00 lib/vsprintf.c:2926
 add_uevent_var+0x1cc/0x450 lib/kobject_uevent.c:679
 ib_device_uevent+0x79/0xa0 drivers/infiniband/core/device.c:529
 dev_uevent+0x48c/0x7a0 drivers/base/core.c:2700
 uevent_show+0x19c/0x310 drivers/base/core.c:2756
 dev_attr_show+0x55/0xc0 drivers/base/core.c:2421
 sysfs_kf_seq_show+0x30d/0x490 fs/sysfs/file.c:65
 seq_read_iter+0x4ea/0xe10 fs/seq_file.c:230
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x557/0xa30 fs/read_write.c:572
 ksys_read+0x145/0x250 fs/read_write.c:715
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f87174a7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff893ff4d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f8717bbf880 RCX: 00007f87174a7407
RDX: 0000000000001000 RSI: 000056318416beb0 RDI: 000000000000000c
RBP: 00007f87175efff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f87175efea0 R14: 0000000000000000 R15: 00005631841875f0
 </TASK>

Allocated by task 6164:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4365 [inline]
 __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4384
 __kmemdup_nul mm/util.c:64 [inline]
 kstrdup+0x42/0x100 mm/util.c:84
 kobject_set_name_vargs+0x61/0x110 lib/kobject.c:274
 dev_set_name+0xd4/0x120 drivers/base/core.c:3492
 assign_name drivers/infiniband/core/device.c:1248 [inline]
 ib_register_device+0x12c/0x1380 drivers/infiniband/core/device.c:1438
 rxe_register_device+0x1ef/0x310 drivers/infiniband/sw/rxe/rxe_verbs.c:1556
 rxe_net_add+0x81/0x110 drivers/infiniband/sw/rxe/rxe_net.c:550
 rxe_newlink+0xdd/0x190 drivers/infiniband/sw/rxe/rxe.c:234
 nldev_newlink+0x4a2/0x5a0 drivers/infiniband/core/nldev.c:1797
 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+0x6ab/0x980 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6243:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:243 [inline]
 __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kfree+0x18e/0x440 mm/slub.c:4879
 kobject_rename+0x38f/0x420 lib/kobject.c:524
 device_rename+0x15d/0x1f0 drivers/base/core.c:4549
 ib_device_rename+0x23d/0x660 drivers/infiniband/core/device.c:429
 nldev_set_doit+0x29f/0x480 drivers/infiniband/core/nldev.c:1147
 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+0x6ab/0x980 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805657e820
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 freed 8-byte region [ffff88805657e820, ffff88805657e828)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5657e
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801a441500 ffffea000082e9c0 dead000000000002
raw: 0000000000000000 0000000000800080 00000000f5000000 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 5858, tgid 5858 (syz-executor), ts 92709635939, free_ts 30697773467
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 __do_kmalloc_node mm/slub.c:4364 [inline]
 __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4384
 __kmemdup_nul mm/util.c:64 [inline]
 kstrdup+0x42/0x100 mm/util.c:84
 kobject_set_name_vargs+0x61/0x110 lib/kobject.c:274
 dev_set_name+0xd4/0x120 drivers/base/core.c:3492
 netdev_register_kobject+0xb7/0x310 net/core/net-sysfs.c:2342
 register_netdevice+0x126c/0x1ae0 net/core/dev.c:11194
 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1034 [inline]
 nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1105
 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1438
 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1494
 nsim_drv_probe+0x88e/0xba0 drivers/net/netdevsim/dev.c:1653
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:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 __free_pages mm/page_alloc.c:5260 [inline]
 free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:7091
 destroy_args+0x64/0x4a0 mm/debug_vm_pgtable.c:958
 debug_vm_pgtable+0x39f/0x3b0 mm/debug_vm_pgtable.c:1340
 do_one_initcall+0x233/0x820 init/main.c:1269
 do_initcall_level+0x104/0x190 init/main.c:1331
 do_initcalls+0x59/0xa0 init/main.c:1347
 kernel_init_freeable+0x334/0x4b0 init/main.c:1579
 kernel_init+0x1d/0x1d0 init/main.c:1469
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88805657e700: 04 fc fc fc 05 fc fc fc 05 fc fc fc 05 fc fc fc
 ffff88805657e780: 05 fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
>ffff88805657e800: 06 fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
                               ^
 ffff88805657e880: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
 ffff88805657e900: fa fc fc fc fa fc fc fc 05 fc fc fc 05 fc fc fc
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