syzbot

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BUG: KASAN: slab-use-after-free in handle_tx+0x1fa/0x640 drivers/net/caif/caif_serial.c:236
Read of size 8 at addr ffff88805a7a8020 by task aoe_tx0/1294

CPU: 0 UID: 0 PID: 1294 Comm: aoe_tx0 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #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
 handle_tx+0x1fa/0x640 drivers/net/caif/caif_serial.c:236
 __netdev_start_xmit include/linux/netdevice.h:5002 [inline]
 netdev_start_xmit include/linux/netdevice.h:5011 [inline]
 xmit_one net/core/dev.c:3590 [inline]
 dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3606
 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4434
 dev_queue_xmit include/linux/netdevice.h:3168 [inline]
 tx+0x6b/0x180 drivers/block/aoe/aoenet.c:62
 kthread+0x23a/0x450 drivers/block/aoe/aoecmd.c:1237
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 6123:
 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+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295
 kmalloc_noprof include/linux/slab.h:879 [inline]
 kzalloc_noprof include/linux/slab.h:1015 [inline]
 alloc_tty_struct+0xa9/0x7d0 drivers/tty/tty_io.c:3116
 tty_init_dev+0x5b/0x4c0 drivers/tty/tty_io.c:1409
 tty_open_by_driver drivers/tty/tty_io.c:2082 [inline]
 tty_open+0x9d9/0xde0 drivers/tty/tty_io.c:2129
 chrdev_open+0x521/0x600 fs/char_dev.c:414
 do_dentry_open+0xbe1/0x1b70 fs/open.c:945
 vfs_open+0x3e/0x330 fs/open.c:1075
 do_open fs/namei.c:3828 [inline]
 path_openat+0x2c84/0x3590 fs/namei.c:3987
 do_filp_open+0x27f/0x4e0 fs/namei.c:4014
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1428
 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

Freed by task 25:
 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:579
 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:2342 [inline]
 slab_free mm/slub.c:4579 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4727
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
 insert_work+0x3e/0x330 kernel/workqueue.c:2183
 __queue_work+0xc8b/0xf50 kernel/workqueue.c:2339
 queue_work_on+0x1c2/0x380 kernel/workqueue.c:2390
 tty_release_struct+0xbc/0xe0 drivers/tty/tty_io.c:1701
 tty_release+0xd06/0x12c0 drivers/tty/tty_io.c:1861
 __fput+0x23c/0xa50 fs/file_table.c:450
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 get_signal+0x16b2/0x1750 kernel/signal.c:3016
 arch_do_signal_or_restart+0x96/0x860 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/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805a7a8000
 which belongs to the cache kmalloc-cg-2k of size 2048
The buggy address is located 32 bytes inside of
 freed 2048-byte region [ffff88805a7a8000, ffff88805a7a8800)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5a7a8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888060b19b81
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801ac4f3c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000080008 00000001f5000000 ffff888060b19b81
head: 00fff00000000040 ffff88801ac4f3c0 dead000000000100 dead000000000122
head: 0000000000000000 0000000000080008 00000001f5000000 ffff888060b19b81
head: 00fff00000000003 ffffea000169ea01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
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 5848, tgid 5848 (syz-executor), ts 66978919236, free_ts 15387151900
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
 prep_new_page mm/page_alloc.c:1564 [inline]
 get_page_from_freelist+0x363e/0x3790 mm/page_alloc.c:3474
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x140 mm/slub.c:2412
 allocate_slab+0x5a/0x2f0 mm/slub.c:2578
 new_slab mm/slub.c:2631 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818
 __slab_alloc+0x58/0xa0 mm/slub.c:3908
 __slab_alloc_node mm/slub.c:3961 [inline]
 slab_alloc_node mm/slub.c:4122 [inline]
 __do_kmalloc_node mm/slub.c:4263 [inline]
 __kmalloc_noprof+0x25a/0x400 mm/slub.c:4276
 kmalloc_noprof include/linux/slab.h:883 [inline]
 kzalloc_noprof include/linux/slab.h:1015 [inline]
 __register_sysctl_table+0xd4/0x1430 fs/proc/proc_sysctl.c:1375
 __devinet_sysctl_register+0x1dc/0x2a0 net/ipv4/devinet.c:2630
 devinet_sysctl_register+0x17e/0x1f0 net/ipv4/devinet.c:2670
 inetdev_init+0x2b4/0x4e0 net/ipv4/devinet.c:299
 inetdev_event+0x340/0x1550 net/ipv4/devinet.c:1598
 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline]
 call_netdevice_notifiers net/core/dev.c:2048 [inline]
 register_netdevice+0x167f/0x1b00 net/core/dev.c:10626
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xded/0x1130 mm/page_alloc.c:2657
 free_contig_range+0x152/0x550 mm/page_alloc.c:6630
 destroy_args+0x92/0x910 mm/debug_vm_pgtable.c:1017
 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397
 do_one_initcall+0x248/0x880 init/main.c:1266
 do_initcall_level+0x157/0x210 init/main.c:1328
 do_initcalls+0x3f/0x80 init/main.c:1344
 kernel_init_freeable+0x435/0x5d0 init/main.c:1577
 kernel_init+0x1d/0x2b0 init/main.c:1466
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff88805a7a7f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805a7a7f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805a7a8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88805a7a8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805a7a8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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