================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:646 [inline] BUG: KASAN: slab-use-after-free in string+0x398/0x3d0 lib/vsprintf.c:728 Read of size 1 at addr ffff88807d559080 by task udevd/7504 CPU: 0 PID: 7504 Comm: udevd Not tainted 6.8.0-rc3-syzkaller-00136-g1f719a2f3fa6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __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:377 [inline] print_report+0xc4/0x620 mm/kasan/report.c:488 kasan_report+0xda/0x110 mm/kasan/report.c:601 string_nocheck lib/vsprintf.c:646 [inline] string+0x398/0x3d0 lib/vsprintf.c:728 vsnprintf+0xc63/0x1870 lib/vsprintf.c:2824 add_uevent_var+0x17c/0x3a0 lib/kobject_uevent.c:665 dev_uevent+0x18b/0x770 drivers/base/core.c:2576 uevent_show+0x1c7/0x390 drivers/base/core.c:2647 dev_attr_show+0x53/0xe0 drivers/base/core.c:2350 sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59 seq_read_iter+0x4fa/0x12c0 fs/seq_file.c:230 kernfs_fop_read_iter+0x417/0x580 fs/kernfs/file.c:279 call_read_iter include/linux/fs.h:2079 [inline] new_sync_read fs/read_write.c:395 [inline] vfs_read+0x6c4/0xb80 fs/read_write.c:476 ksys_read+0x12f/0x260 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fbe1ff16b6a 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:00007ffe4283f958 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055f7592c8290 RCX: 00007fbe1ff16b6a RDX: 0000000000001000 RSI: 000055f7592929f0 RDI: 0000000000000008 RBP: 000055f7592c8290 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffe4283fe38 R15: 000000000000000a Allocated by task 19767: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:372 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:389 kmalloc include/linux/slab.h:590 [inline] raw_ioctl_init+0x163/0x840 drivers/usb/gadget/legacy/raw_gadget.c:509 raw_ioctl+0x9dd/0x2b90 drivers/usb/gadget/legacy/raw_gadget.c:1303 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 Freed by task 19767: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640 poison_slab_object mm/kasan/common.c:241 [inline] __kasan_slab_free+0x121/0x1c0 mm/kasan/common.c:257 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kfree+0x124/0x370 mm/slub.c:4409 dev_free+0x9a/0x700 drivers/usb/gadget/legacy/raw_gadget.c:211 kref_put include/linux/kref.h:65 [inline] raw_release+0x188/0x2f0 drivers/usb/gadget/legacy/raw_gadget.c:473 __fput+0x270/0xb80 fs/file_table.c:376 task_work_run+0x14f/0x250 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa8a/0x2ad0 kernel/exit.c:871 do_group_exit+0xd4/0x2a0 kernel/exit.c:1020 get_signal+0x23b9/0x2790 kernel/signal.c:2893 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x156/0x2b0 kernel/entry/common.c:212 do_syscall_64+0xe5/0x270 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6f/0x77 The buggy address belongs to the object at ffff88807d559080 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff88807d559080, ffff88807d5590a0) The buggy address belongs to the physical page: page:ffffea0001f55640 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d559 anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888014c41500 ffffea00008b7f80 dead000000000005 raw: 0000000000000000 0000000000200020 00000001ffffffff 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5919, tgid 5917 (syz-executor.3), ts 283886301627, free_ts 283144004043 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311 __alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2190 [inline] allocate_slab mm/slub.c:2354 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2407 ___slab_alloc+0x4af/0x19a0 mm/slub.c:3540 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3625 __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmalloc_trace+0x30b/0x340 mm/slub.c:4007 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:711 [inline] ref_tracker_alloc+0x17c/0x5b0 lib/ref_tracker.c:203 __netns_tracker_alloc include/net/net_namespace.h:333 [inline] netns_tracker_alloc include/net/net_namespace.h:342 [inline] get_net_track include/net/net_namespace.h:359 [inline] sk_alloc+0x1fe/0xb90 net/core/sock.c:2144 __netlink_create+0x63/0x380 net/netlink/af_netlink.c:647 netlink_create+0x3dc/0x670 net/netlink/af_netlink.c:712 __sock_create+0x32e/0x800 net/socket.c:1571 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x150/0x260 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 page last free pid 5890 tgid 5890 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2346 free_unref_page_list+0xe6/0xb40 mm/page_alloc.c:2532 release_pages+0x32a/0x14f0 mm/swap.c:1042 tlb_batch_pages_flush+0x9a/0x190 mm/mmu_gather.c:98 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] tlb_flush_mmu mm/mmu_gather.c:300 [inline] tlb_finish_mmu+0x14b/0x700 mm/mmu_gather.c:392 exit_mmap+0x3da/0xb50 mm/mmap.c:3292 __mmput+0x12a/0x4d0 kernel/fork.c:1343 mmput+0x62/0x70 kernel/fork.c:1365 exit_mm kernel/exit.c:569 [inline] do_exit+0x9a5/0x2ad0 kernel/exit.c:858 do_group_exit+0xd4/0x2a0 kernel/exit.c:1020 __do_sys_exit_group kernel/exit.c:1031 [inline] __se_sys_exit_group kernel/exit.c:1029 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1029 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 Memory state around the buggy address: ffff88807d558f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807d559000: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807d559080: fa fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88807d559100: fa fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff88807d559180: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc 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