================================================================== BUG: KASAN: slab-out-of-bounds in instrument_atomic_read include/linux/instrumented.h:72 [inline] BUG: KASAN: slab-out-of-bounds in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: slab-out-of-bounds in buffer_busy fs/buffer.c:2784 [inline] BUG: KASAN: slab-out-of-bounds in drop_buffers+0x65/0x6a0 fs/buffer.c:2796 Read of size 4 at addr ffff8880285329e0 by task kswapd0/81 CPU: 1 PID: 81 Comm: kswapd0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:72 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] buffer_busy fs/buffer.c:2784 [inline] drop_buffers+0x65/0x6a0 fs/buffer.c:2796 try_to_free_buffers+0x205/0x520 fs/buffer.c:2826 shrink_folio_list+0x2127/0x7aa0 mm/vmscan.c:2003 evict_folios+0xa80/0x22a0 mm/vmscan.c:5046 lru_gen_shrink_lruvec mm/vmscan.c:5229 [inline] shrink_lruvec+0xc90/0x3d50 mm/vmscan.c:5924 Allocated by task 4366: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc+0xb0/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] iomap_page_create+0x14a/0x600 fs/iomap/buffered-io.c:61 iomap_readpage_iter+0x240/0x8f0 fs/iomap/buffered-io.c:273 iomap_read_folio+0x332/0x8c0 fs/iomap/buffered-io.c:344 filemap_read_folio+0x16b/0x770 mm/filemap.c:2490 do_read_cache_folio+0x2a0/0x760 mm/filemap.c:3659 erofs_bread+0x18e/0x670 fs/erofs/data.c:50 erofs_find_target_block fs/erofs/namei.c:102 [inline] erofs_namei+0x29c/0xf50 fs/erofs/namei.c:175 erofs_lookup+0x14b/0x390 fs/erofs/namei.c:204 lookup_open fs/namei.c:3468 [inline] open_last_lookups fs/namei.c:3558 [inline] path_openat+0xfce/0x2ee0 fs/namei.c:3788 do_filp_open+0x1f1/0x430 fs/namei.c:3818 do_sys_openat2+0x150/0x4b0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888028532980 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes to the right of 96-byte region [ffff888028532980, ffff8880285329e0) The buggy address belongs to the physical page: page:ffffea0000a14c80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888028532800 pfn:0x28532 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0000b9cf08 ffffea0001522588 ffff888017441780 raw: ffff888028532800 000000000020001a 00000001ffffffff 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 4344, tgid 4344 (kworker/0:4), ts 63033756891, free_ts 57289064668 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5643 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] nsim_fib6_rt_create drivers/net/netdevsim/fib.c:547 [inline] nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:752 [inline] nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline] nsim_fib_event_work+0x12a9/0x3450 drivers/net/netdevsim/fib.c:1494 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 process_scheduled_works kernel/workqueue.c:2355 [inline] worker_thread+0xd27/0x1270 kernel/workqueue.c:2441 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] kset_create lib/kobject.c:950 [inline] kset_create_and_add+0x56/0x160 lib/kobject.c:993 register_queue_kobjects net/core/net-sysfs.c:1764 [inline] netdev_register_kobject+0x1ae/0x320 net/core/net-sysfs.c:2017 register_netdevice+0x12dc/0x1b00 net/core/dev.c:10217 register_vlan_dev+0x393/0x810 net/8021q/vlan.c:180 vlan_newlink+0x442/0x590 net/8021q/vlan_netlink.c:195 rtnl_newlink_create net/core/rtnetlink.c:3422 [inline] __rtnl_newlink net/core/rtnetlink.c:3642 [inline] rtnl_newlink+0x1542/0x2080 net/core/rtnetlink.c:3655 Memory state around the buggy address: ffff888028532880: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff888028532900: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888028532980: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff888028532a00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff888028532a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================