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BUG: KASAN: slab-use-after-free in ptep_get include/linux/pgtable.h:338 [inline]
BUG: KASAN: slab-use-after-free in filemap_map_folio_range mm/filemap.c:3632 [inline]
BUG: KASAN: slab-use-after-free in filemap_map_pages+0xf14/0x1900 mm/filemap.c:3748
Read of size 8 at addr ffff88807f491000 by task syz.4.175/6736

CPU: 0 UID: 0 PID: 6736 Comm: syz.4.175 Not tainted 6.13.0-rc3-next-20241220-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
 ptep_get include/linux/pgtable.h:338 [inline]
 filemap_map_folio_range mm/filemap.c:3632 [inline]
 filemap_map_pages+0xf14/0x1900 mm/filemap.c:3748
 do_fault_around mm/memory.c:5351 [inline]
 do_read_fault mm/memory.c:5384 [inline]
 do_fault mm/memory.c:5527 [inline]
 do_pte_missing mm/memory.c:4048 [inline]
 handle_pte_fault+0x3888/0x5ee0 mm/memory.c:5890
 __handle_mm_fault mm/memory.c:6033 [inline]
 handle_mm_fault+0x11f5/0x1d50 mm/memory.c:6202
 faultin_page mm/gup.c:1196 [inline]
 __get_user_pages+0x1a92/0x4140 mm/gup.c:1491
 populate_vma_page_range+0x264/0x330 mm/gup.c:1929
 __mm_populate+0x27a/0x460 mm/gup.c:2032
 mm_populate include/linux/mm.h:3400 [inline]
 vm_mmap_pgoff+0x303/0x430 mm/util.c:585
 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:607
 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: 0033:0x7f01d6585d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f01d7457038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f01d6775fa0 RCX: 00007f01d6585d29
RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007f01d6601b08 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f01d6775fa0 R15: 00007ffd5ba3b4f8
 </TASK>

Allocated by task 2972:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4115 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4216
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1323 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x261/0xb50 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 2972:
 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:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kmem_cache_free+0x195/0x410 mm/slub.c:4711
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
 nsim_dev_trap_report_work+0x7cc/0xb50 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff88807f491000
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 0 bytes inside of
 freed 240-byte region [ffff88807f491000, ffff88807f4910f0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f491
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff8881422e5780 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000c000c 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 2972, tgid 2972 (kworker/u8:6), ts 153968693384, free_ts 153648494551
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4754
 alloc_pages_mpol+0x30e/0x550 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2587
 new_slab mm/slub.c:2640 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826
 __slab_alloc+0x58/0xa0 mm/slub.c:3916
 __slab_alloc_node mm/slub.c:3991 [inline]
 slab_alloc_node mm/slub.c:4152 [inline]
 kmem_cache_alloc_node_noprof+0x269/0x380 mm/slub.c:4216
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1323 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x261/0xb50 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
page last free pid 16 tgid 16 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660
 __folio_put+0x2b3/0x360 mm/swap.c:112
 __tlb_remove_table arch/x86/include/asm/tlb.h:34 [inline]
 __tlb_remove_table_free mm/mmu_gather.c:227 [inline]
 tlb_remove_table_rcu+0x76/0xf0 mm/mmu_gather.c:282
 rcu_do_batch kernel/rcu/tree.c:2546 [inline]
 rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff88807f490f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807f490f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807f491000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88807f491080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff88807f491100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
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