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BUG: KASAN: slab-use-after-free in JFS_SBI fs/jfs/jfs_incore.h:217 [inline]
BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x12e/0xa10 fs/jfs/jfs_txnmgr.c:2716
Read of size 8 at addr ffff888033e4a798 by task jfsCommit/129

CPU: 1 UID: 0 PID: 129 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 JFS_SBI fs/jfs/jfs_incore.h:217 [inline]
 jfs_lazycommit+0x12e/0xa10 fs/jfs/jfs_txnmgr.c:2716
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 43:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5296 [inline]
 __kmalloc_node_track_caller_noprof+0x372/0x7e0 mm/slub.c:5408
 kmalloc_reserve net/core/skbuff.c:635 [inline]
 __alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1385 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
 nsim_dev_trap_report_work+0x29f/0xbd0 drivers/net/netdevsim/dev.c:922
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 43:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2689 [inline]
 slab_free mm/slub.c:6251 [inline]
 kfree+0x1c5/0x6c0 mm/slub.c:6566
 skb_kfree_head net/core/skbuff.c:1075 [inline]
 skb_free_head net/core/skbuff.c:1087 [inline]
 skb_release_data+0x828/0xa60 net/core/skbuff.c:1114
 skb_release_all net/core/skbuff.c:1189 [inline]
 __kfree_skb+0x5d/0x210 net/core/skbuff.c:1203
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline]
 nsim_dev_trap_report_work+0x809/0xbd0 drivers/net/netdevsim/dev.c:922
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888033e4a000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1944 bytes inside of
 freed 4096-byte region [ffff888033e4a000, ffff888033e4b000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33e48
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88801a00a140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88801a00a140 dead000000000100 dead000000000122
head: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000
head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4980, tgid 4980 (udevadm), ts 27630305474, free_ts 27627989921
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x28b2/0x2930 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3467
 new_slab mm/slub.c:3525 [inline]
 refill_objects+0x33c/0x3d0 mm/slub.c:7272
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4652
 alloc_from_pcs mm/slub.c:4750 [inline]
 slab_alloc_node mm/slub.c:4884 [inline]
 __kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5415
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 kernfs_iop_get_link+0x66/0x6c0 fs/kernfs/symlink.c:137
 vfs_readlink+0x24a/0x540 fs/namei.c:6265
 do_readlinkat+0x218/0x510 fs/stat.c:583
 __do_sys_readlink fs/stat.c:605 [inline]
 __se_sys_readlink fs/stat.c:602 [inline]
 __x64_sys_readlink+0x7f/0x90 fs/stat.c:602
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 20 tgid 20 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0xfe5/0x10d0 mm/page_alloc.c:2938
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core kernel/rcu/tree.c:2869 [inline]
 rcu_cpu_kthread+0x99e/0x1470 kernel/rcu/tree.c:2957
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888033e4a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888033e4a700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888033e4a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888033e4a800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888033e4a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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