================================================================== BUG: KASAN: slab-use-after-free in iov_iter_folioq_advance+0x10c/0x360 lib/iov_iter.c:540 Read of size 8 at addr ffff888030179120 by task syz.2.86/5783 CPU: 1 UID: 0 PID: 5783 Comm: syz.2.86 Not tainted 6.11.0-next-20240924-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __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:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 iov_iter_folioq_advance+0x10c/0x360 lib/iov_iter.c:540 netfs_write_folio+0x154b/0x1fe0 fs/netfs/write_issue.c:481 netfs_writepages+0x89f/0xe80 fs/netfs/write_issue.c:541 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:399 __filemap_fdatawrite_range mm/filemap.c:432 [inline] __filemap_fdatawrite mm/filemap.c:438 [inline] filemap_fdatawrite+0xf5/0x150 mm/filemap.c:443 v9fs_dir_release+0x151/0x560 fs/9p/vfs_dir.c:219 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f297077def9 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:00007ffec2206038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f2970937a80 RCX: 00007f297077def9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f2970937a80 R08: 00007f2970922000 R09: 00007ffec220632f R10: 00000000005ef8ec R11: 0000000000000246 R12: 000000000001cc9e R13: 00007ffec2206140 R14: 0000000000000032 R15: ffffffffffffffff Allocated by task 5783: 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:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4296 kmalloc_noprof include/linux/slab.h:878 [inline] netfs_buffer_append_folio+0x1f1/0x8b0 fs/netfs/misc.c:25 netfs_write_folio+0xe69/0x1fe0 fs/netfs/write_issue.c:421 netfs_writepages+0x89f/0xe80 fs/netfs/write_issue.c:541 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:399 __filemap_fdatawrite_range mm/filemap.c:432 [inline] __filemap_fdatawrite mm/filemap.c:438 [inline] filemap_fdatawrite+0xf5/0x150 mm/filemap.c:443 v9fs_dir_release+0x151/0x560 fs/9p/vfs_dir.c:219 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 148: 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:230 [inline] slab_free_hook mm/slub.c:2343 [inline] slab_free mm/slub.c:4580 [inline] kfree+0x1a0/0x440 mm/slub.c:4728 netfs_delete_buffer_head+0x9f/0xd0 fs/netfs/misc.c:59 netfs_writeback_unlock_folios fs/netfs/write_collect.c:139 [inline] netfs_collect_write_results fs/netfs/write_collect.c:493 [inline] netfs_write_collection_worker+0x1b9a/0x4950 fs/netfs/write_collect.c:551 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 The buggy address belongs to the object at ffff888030179000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 288 bytes inside of freed 512-byte region [ffff888030179000, ffff888030179200) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30178 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac41c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac41c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000 head: 00fff00000000002 ffffea0000c05e01 ffffffffffffffff 0000000000000000 head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5229, tgid 5229 (syz-executor), ts 73058900880, free_ts 73055275182 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x120 mm/slub.c:2413 allocate_slab+0x5a/0x2f0 mm/slub.c:2579 new_slab mm/slub.c:2632 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819 __slab_alloc+0x58/0xa0 mm/slub.c:3909 __slab_alloc_node mm/slub.c:3962 [inline] slab_alloc_node mm/slub.c:4123 [inline] __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4291 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] nsim_dev_traps_init+0x5f/0x4b0 drivers/net/netdevsim/dev.c:865 nsim_drv_probe+0x66d/0xb80 drivers/net/netdevsim/dev.c:1574 really_probe+0x2b8/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459 page last free pid 5227 tgid 5227 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 stack_depot_save_flags+0x6f6/0x830 lib/stackdepot.c:666 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x51/0x80 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:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4142 fill_pool lib/debugobjects.c:168 [inline] debug_objects_fill_pool+0x6e1/0x9f0 lib/debugobjects.c:615 debug_object_assert_init+0x12e/0x440 lib/debugobjects.c:893 debug_timer_assert_init kernel/time/timer.c:845 [inline] debug_assert_init kernel/time/timer.c:890 [inline] __timer_delete+0xad/0x380 kernel/time/timer.c:1412 del_timer include/linux/timer.h:202 [inline] try_to_grab_pending kernel/workqueue.c:2064 [inline] work_grab_pending+0x157/0xae0 kernel/workqueue.c:2157 __cancel_work+0xbb/0x390 kernel/workqueue.c:4308 __cancel_work_sync+0x1f/0x110 kernel/workqueue.c:4325 devlink_port_type_warn_cancel net/devlink/port.c:1006 [inline] __devlink_port_type_set+0x177/0x6b0 net/devlink/port.c:1207 devlink_port_netdevice_event+0x296/0x4d0 net/devlink/port.c:1311 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:10520 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:690 [inline] nsim_create+0x647/0x890 drivers/net/netdevsim/netdev.c:750 Memory state around the buggy address: ffff888030179000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888030179080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888030179100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888030179180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888030179200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================