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BUG: KASAN: slab-out-of-bounds in iov_iter_revert lib/iov_iter.c:633 [inline]
BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x443/0x5a0 lib/iov_iter.c:611
Read of size 4 at addr ffff88806aa91138 by task kworker/u32:0/12

CPU: 0 UID: 0 PID: 12 Comm: kworker/u32:0 Not tainted 6.15.0-rc2-syzkaller-00404-g8560697b23dc #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound netfs_write_collection_worker
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 iov_iter_revert lib/iov_iter.c:633 [inline]
 iov_iter_revert+0x443/0x5a0 lib/iov_iter.c:611
 netfs_retry_write_stream fs/netfs/write_retry.c:44 [inline]
 netfs_retry_writes+0x166d/0x1a50 fs/netfs/write_retry.c:231
 netfs_collect_write_results fs/netfs/write_collect.c:352 [inline]
 netfs_write_collection_worker+0x23fd/0x3830 fs/netfs/write_collect.c:374
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 7374:
 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:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:905 [inline]
 proc_thread_self_get_link+0x1c6/0x240 fs/proc/thread_self.c:22
 pick_link fs/namei.c:1928 [inline]
 step_into+0x19e4/0x2270 fs/namei.c:1998
 walk_component+0xfc/0x5b0 fs/namei.c:2134
 link_path_walk.part.0.constprop.0+0x685/0xd60 fs/namei.c:2493
 link_path_walk fs/namei.c:2425 [inline]
 path_openat+0x227/0x2d40 fs/namei.c:4000
 do_filp_open+0x20b/0x470 fs/namei.c:4031
 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_compat_sys_openat fs/open.c:1506 [inline]
 __se_compat_sys_openat fs/open.c:1504 [inline]
 __ia32_compat_sys_openat+0x16d/0x210 fs/open.c:1504
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 7374:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2398 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x2b6/0x4d0 mm/slub.c:4855
 do_delayed_call include/linux/delayed_call.h:28 [inline]
 put_link fs/namei.c:1093 [inline]
 walk_component+0x1a2/0x5b0 fs/namei.c:2133
 link_path_walk.part.0.constprop.0+0x553/0xd60 fs/namei.c:2490
 link_path_walk fs/namei.c:2425 [inline]
 path_openat+0x227/0x2d40 fs/namei.c:4000
 do_filp_open+0x20b/0x470 fs/namei.c:4031
 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_compat_sys_openat fs/open.c:1506 [inline]
 __se_compat_sys_openat fs/open.c:1504 [inline]
 __ia32_compat_sys_openat+0x16d/0x210 fs/open.c:1504
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff88806aa91100
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 24 bytes to the right of
 allocated 32-byte region [ffff88806aa91100, ffff88806aa91120)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6aa91
anon flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000000 ffff88801b442780 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000400040 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 0x52c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6505, tgid 6505 (syz-executor), ts 70559691660, free_ts 70500712241
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x135c/0x3920 mm/page_alloc.c:3700
 __alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4982
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab mm/slub.c:2632 [inline]
 new_slab+0x244/0x340 mm/slub.c:2686
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3872
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3962
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 __do_kmalloc_node mm/slub.c:4340 [inline]
 __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45
 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
 tomoyo_path_perm+0x3a5/0x460 security/tomoyo/file.c:831
 tomoyo_path_symlink+0x97/0xe0 security/tomoyo/tomoyo.c:212
 security_path_symlink+0x152/0x2e0 security/security.c:1984
 do_symlinkat+0x10d/0x310 fs/namei.c:4712
 __do_sys_symlinkat fs/namei.c:4730 [inline]
 __se_sys_symlinkat fs/namei.c:4727 [inline]
 __ia32_sys_symlinkat+0x93/0xc0 fs/namei.c:4727
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/syscall_32.c:306
page last free pid 15 tgid 15 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725
 pagetable_free include/linux/mm.h:3002 [inline]
 pagetable_dtor_free include/linux/mm.h:3100 [inline]
 __tlb_remove_table include/asm-generic/tlb.h:215 [inline]
 __tlb_remove_table_free mm/mmu_gather.c:227 [inline]
 tlb_remove_table_rcu+0x116/0x1a0 mm/mmu_gather.c:290
 rcu_do_batch kernel/rcu/tree.c:2568 [inline]
 rcu_core+0x799/0x14e0 kernel/rcu/tree.c:2824
 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
 run_ksoftirqd kernel/softirq.c:968 [inline]
 run_ksoftirqd+0x3a/0x60 kernel/softirq.c:960
 smpboot_thread_fn+0x3f4/0xae0 kernel/smpboot.c:164
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88806aa91000: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88806aa91080: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88806aa91100: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc
                                        ^
 ffff88806aa91180: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88806aa91200: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
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