iommufd_mock iommufd_mock0: Adding to iommu group 0
==================================================================
BUG: KASAN: slab-use-after-free in software_node_notify_remove+0x1bc/0x1c0 drivers/base/swnode.c:1108
Read of size 1 at addr ffff88802375bd08 by task syz.3.972/9096

CPU: 0 UID: 0 PID: 9096 Comm: syz.3.972 Not tainted 6.14.0-syzkaller-13423-ga8662bcd2ff1 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 software_node_notify_remove+0x1bc/0x1c0 drivers/base/swnode.c:1108
 device_platform_notify_remove drivers/base/core.c:2387 [inline]
 device_del+0x594/0x9b0 drivers/base/core.c:3858
 device_unregister+0x20/0xc0 drivers/base/core.c:3896
 iommufd_fops_release+0x1bd/0x390 drivers/iommu/iommufd/main.c:261
 __fput+0x3e9/0x9f0 fs/file_table.c:465
 task_work_run+0x251/0x310 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa11/0x27f0 kernel/exit.c:953
 do_group_exit+0x207/0x2c0 kernel/exit.c:1102
 get_signal+0x1696/0x1730 kernel/signal.c:3034
 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1c9538d169
Code: Unable to access opcode bytes at 0x7f1c9538d13f.
RSP: 002b:00007f1c961d60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f1c955a5fa8 RCX: 00007f1c9538d169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1c955a5fa8
RBP: 00007f1c955a5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1c955a5fac
R13: 0000000000000000 R14: 00007f1c956cf940 R15: 00007f1c956cfa28
 </TASK>

Allocated by task 9096:
 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+0x9d/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x236/0x370 mm/slub.c:4362
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 swnode_register+0x5a/0x540 drivers/base/swnode.c:790
 fwnode_create_software_node+0x199/0x1f0 drivers/base/swnode.c:949
 device_create_managed_software_node+0xd5/0x1f0 drivers/base/swnode.c:1060
 mock_dev_create drivers/iommu/iommufd/selftest.c:942 [inline]
 iommufd_test_mock_domain drivers/iommu/iommufd/selftest.c:989 [inline]
 iommufd_test+0x3335/0x56a0 drivers/iommu/iommufd/selftest.c:1866
 iommufd_fops_ioctl+0x4fc/0x610 drivers/iommu/iommufd/main.c:419
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 9096:
 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:576
 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:2389 [inline]
 slab_free mm/slub.c:4646 [inline]
 kfree+0x198/0x430 mm/slub.c:4845
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 software_node_notify_remove+0x159/0x1c0 drivers/base/swnode.c:1106
 device_platform_notify_remove drivers/base/core.c:2387 [inline]
 device_del+0x594/0x9b0 drivers/base/core.c:3858
 device_unregister+0x20/0xc0 drivers/base/core.c:3896
 iommufd_fops_release+0x1bd/0x390 drivers/iommu/iommufd/main.c:261
 __fput+0x3e9/0x9f0 fs/file_table.c:465
 task_work_run+0x251/0x310 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa11/0x27f0 kernel/exit.c:953
 do_group_exit+0x207/0x2c0 kernel/exit.c:1102
 get_signal+0x1696/0x1730 kernel/signal.c:3034
 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802375bc00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 264 bytes inside of
 freed 512-byte region [ffff88802375bc00, ffff88802375be00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23758
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b041c80 ffffea000048ff00 0000000000000003
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b041c80 ffffea000048ff00 0000000000000003
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00008dd601 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 8626, tgid 8625 (syz.1.827), ts 263275605278, free_ts 263139062635
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1717
 prep_new_page mm/page_alloc.c:1725 [inline]
 get_page_from_freelist+0x352b/0x36c0 mm/page_alloc.c:3652
 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934
 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2459 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2623
 new_slab mm/slub.c:2676 [inline]
 ___slab_alloc+0xc3b/0x1500 mm/slub.c:3862
 __slab_alloc+0x58/0xa0 mm/slub.c:3952
 __slab_alloc_node mm/slub.c:4027 [inline]
 slab_alloc_node mm/slub.c:4188 [inline]
 __do_kmalloc_node mm/slub.c:4330 [inline]
 __kmalloc_noprof+0x2ea/0x4d0 mm/slub.c:4343
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 copy_splice_read+0x181/0xb50 fs/splice.c:337
 do_splice_read fs/splice.c:978 [inline]
 splice_direct_to_actor+0x4f0/0xc90 fs/splice.c:1083
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0x281/0x3d0 fs/splice.c:1227
 do_sendfile+0x582/0x8c0 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64+0x17e/0x1e0 fs/read_write.c:1415
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 8626 tgid 8625 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2680
 discard_slab mm/slub.c:2720 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3189
 put_cpu_partial+0x17e/0x250 mm/slub.c:3264
 __slab_free+0x294/0x390 mm/slub.c:4516
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4151 [inline]
 slab_alloc_node mm/slub.c:4200 [inline]
 __do_kmalloc_node mm/slub.c:4330 [inline]
 __kmalloc_noprof+0x238/0x4d0 mm/slub.c:4343
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 copy_splice_read+0x181/0xb50 fs/splice.c:337
 do_splice_read fs/splice.c:978 [inline]
 splice_direct_to_actor+0x4f0/0xc90 fs/splice.c:1083
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0x281/0x3d0 fs/splice.c:1227
 do_sendfile+0x582/0x8c0 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64+0x17e/0x1e0 fs/read_write.c:1415
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802375bc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802375bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802375bd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88802375bd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802375be00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================