================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:645 [inline] BUG: KASAN: slab-use-after-free in string+0x54/0x12c lib/vsprintf.c:728 Read at addr fcf00000077bca60 by task udevd/19878 Pointer tag: [fc], memory tag: [fe] CPU: 0 PID: 19878 Comm: udevd Not tainted 6.10.0-rc2-syzkaller #0 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x94/0xec arch/arm64/kernel/stacktrace.c:317 show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:324 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x78/0x90 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x108/0x618 mm/kasan/report.c:488 kasan_report+0x88/0xac mm/kasan/report.c:601 report_tag_fault arch/arm64/mm/fault.c:331 [inline] do_tag_recovery arch/arm64/mm/fault.c:343 [inline] __do_kernel_fault+0x1a0/0x1dc arch/arm64/mm/fault.c:385 do_bad_area arch/arm64/mm/fault.c:485 [inline] do_tag_check_fault+0x78/0x8c arch/arm64/mm/fault.c:750 do_mem_abort+0x44/0x94 arch/arm64/mm/fault.c:826 el1_abort+0x40/0x60 arch/arm64/kernel/entry-common.c:432 el1h_64_sync_handler+0xd8/0xe4 arch/arm64/kernel/entry-common.c:492 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:593 string_nocheck lib/vsprintf.c:645 [inline] string+0x54/0x12c lib/vsprintf.c:728 vsnprintf+0x238/0x6dc lib/vsprintf.c:2824 add_uevent_var+0x8c/0x128 lib/kobject_uevent.c:664 dev_uevent+0x70/0x1e4 drivers/base/core.c:2672 uevent_show+0x8c/0x114 drivers/base/core.c:2743 dev_attr_show+0x20/0x6c drivers/base/core.c:2437 sysfs_kf_seq_show+0x8c/0x104 fs/sysfs/file.c:59 kernfs_seq_show+0x2c/0x38 fs/kernfs/file.c:205 seq_read_iter+0x164/0x47c fs/seq_file.c:230 kernfs_fop_read_iter+0x150/0x1bc fs/kernfs/file.c:279 new_sync_read fs/read_write.c:395 [inline] vfs_read+0x268/0x310 fs/read_write.c:476 ksys_read+0x70/0x104 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [inline] __se_sys_read fs/read_write.c:627 [inline] __arm64_sys_read+0x1c/0x28 fs/read_write.c:627 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x48/0x118 arch/arm64/kernel/syscall.c:48 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:133 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:152 el0_svc+0x34/0xf8 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 Allocated by task 19899: kasan_save_stack+0x3c/0x64 mm/kasan/common.c:47 save_stack_info+0x40/0x158 mm/kasan/tags.c:106 kasan_save_alloc_info+0x14/0x20 mm/kasan/tags.c:142 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] poison_kmalloc_redzone mm/kasan/common.c:343 [inline] __kasan_kmalloc+0xb4/0xb8 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace_noprof+0x150/0x2e4 mm/slub.c:4152 kmalloc_noprof include/linux/slab.h:660 [inline] raw_ioctl_init+0x10c/0x2e8 drivers/usb/gadget/legacy/raw_gadget.c:509 raw_ioctl+0x4dc/0xcac drivers/usb/gadget/legacy/raw_gadget.c:1303 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0xac/0xf0 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x48/0x118 arch/arm64/kernel/syscall.c:48 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:133 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:152 el0_svc+0xac/0xf8 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 Freed by task 19898: kasan_save_stack+0x3c/0x64 mm/kasan/common.c:47 save_stack_info+0x40/0x158 mm/kasan/tags.c:106 kasan_save_free_info+0x18/0x24 mm/kasan/tags.c:147 poison_slab_object+0x178/0x1c0 mm/kasan/common.c:240 __kasan_slab_free+0x30/0x48 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2195 [inline] slab_free mm/slub.c:4436 [inline] kfree+0xd8/0x28c mm/slub.c:4557 dev_free+0x30/0x120 drivers/usb/gadget/legacy/raw_gadget.c:211 kref_put include/linux/kref.h:65 [inline] raw_release+0xb0/0x188 drivers/usb/gadget/legacy/raw_gadget.c:473 __fput+0xc4/0x2cc fs/file_table.c:422 __fput_sync+0x50/0x5c fs/file_table.c:507 __do_sys_close fs/open.c:1555 [inline] __se_sys_close fs/open.c:1540 [inline] __arm64_sys_close+0x38/0x7c fs/open.c:1540 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x48/0x118 arch/arm64/kernel/syscall.c:48 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:133 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:152 el0_svc+0x34/0xf8 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 The buggy address belongs to the object at fff00000077bca60 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [fff00000077bca60, fff00000077bca80) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x477bc flags: 0x1ffc00000000000(node=0|zone=0|lastcpupid=0x7ff|kasantag=0x0) page_type: 0xffffefff(slab) raw: 01ffc00000000000 f0f0000002c01500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080800080 00000001ffffefff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: fff00000077bc800: f5 f5 fd fd f8 f8 fe fe f9 f9 fd fd f5 f5 fe fe fff00000077bc900: fa fa f4 f4 fd fd fb fb f4 f4 fe fe f3 f3 f0 f0 >fff00000077bca00: f5 f5 fa fa fc fc fe fe fa fa fb fb fa fa f6 f6 ^ fff00000077bcb00: f7 f7 f7 f7 f7 f7 f8 f8 f7 f7 fa fa f4 f4 f9 f9 fff00000077bcc00: f0 f0 f0 f0 fe fe fb fb f2 f2 f2 f2 f8 f8 f7 f7 ==================================================================