loop0: detected capacity change from 0 to 1024 ======================================================= WARNING: The mand mount option has been deprecated and and is ignored by this kernel. Remove the mand option from the mount to silence this warning. ======================================================= EXT4-fs: Ignoring removed oldalloc option EXT4-fs: Ignoring removed orlov option EXT4-fs (loop0): stripe (2) is not aligned with cluster size (16), stripe is disabled EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. ================================================================== BUG: KASAN: slab-use-after-free in ext4_ext_binsearch fs/ext4/extents.c:841 [inline] BUG: KASAN: slab-use-after-free in ext4_find_extent+0xae6/0xcc0 fs/ext4/extents.c:956 Read of size 4 at addr ffff8880006a583c by task syz.0.0/5331 CPU: 0 UID: 0 PID: 5331 Comm: syz.0.0 Not tainted syzkaller #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 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ext4_ext_binsearch fs/ext4/extents.c:841 [inline] ext4_find_extent+0xae6/0xcc0 fs/ext4/extents.c:956 ext4_ext_map_blocks+0x278/0x69c0 fs/ext4/extents.c:4208 ext4_map_create_blocks fs/ext4/inode.c:613 [inline] ext4_map_blocks+0x82c/0x16f0 fs/ext4/inode.c:816 _ext4_get_block+0x1fa/0x4c0 fs/ext4/inode.c:916 ext4_get_block_unwritten+0x2e/0x100 fs/ext4/inode.c:949 ext4_block_write_begin+0xb03/0x1940 fs/ext4/inode.c:1203 ext4_write_begin+0xb3a/0x1860 fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x352/0xd30 fs/ext4/inode.c:3130 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314 ext4_buffered_write_iter+0xce/0x3a0 fs/ext4/file.c:299 ext4_file_write_iter+0x292/0x1bc0 fs/ext4/file.c:-1 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffb1058f7c9 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:00007ffb1135f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffb107e5fa0 RCX: 00007ffb1058f7c9 RDX: 00000000fffffdef RSI: 00002000000000c0 RDI: 0000000000000008 RBP: 00007ffb10613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffb107e6038 R14: 00007ffb107e5fa0 R15: 00007ffc30bb7438 Allocated by task 5024: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_node_noprof+0x43c/0x720 mm/slub.c:5315 alloc_task_struct_node kernel/fork.c:184 [inline] dup_task_struct+0x57/0x9a0 kernel/fork.c:915 copy_process+0x4ea/0x3950 kernel/fork.c:2052 kernel_clone+0x21e/0x820 kernel/fork.c:2651 __do_sys_clone3 kernel/fork.c:2953 [inline] __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2932 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6668 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6779 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xd70/0x1870 kernel/rcu/tree.c:2857 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:1063 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3119 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3239 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xd70/0x1870 kernel/rcu/tree.c:2857 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:1063 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3119 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3239 context_switch kernel/sched/core.c:5259 [inline] __schedule+0x14c4/0x5000 kernel/sched/core.c:6863 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] finish_fault+0xfb4/0x1250 mm/memory.c:5625 do_cow_fault mm/memory.c:5797 [inline] do_fault mm/memory.c:5891 [inline] do_pte_missing+0x1caf/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 The buggy address belongs to the object at ffff8880006a4980 which belongs to the cache task_struct of size 9152 The buggy address is located 3772 bytes inside of freed 9152-byte region [ffff8880006a4980, ffff8880006a6d40) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880006a4980 pfn:0x6a0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x7ff00000000240(workingset|head|node=0|zone=0|lastcpupid=0x7ff) page_type: f5(slab) raw: 007ff00000000240 ffff88803040b500 ffffea0000037a10 ffffea0000037e10 raw: ffff8880006a4980 0000000000030002 00000000f5000000 0000000000000000 head: 007ff00000000240 ffff88803040b500 ffffea0000037a10 ffffea0000037e10 head: ffff8880006a4980 0000000000030002 00000000f5000000 0000000000000000 head: 007ff00000000003 ffffea000001a801 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 25, tgid 25 (kworker/u4:2), ts 9053777994, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf2b/0x1960 mm/slub.c:4656 __slab_alloc+0x65/0x100 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] kmem_cache_alloc_node_noprof+0x4ce/0x720 mm/slub.c:5315 alloc_task_struct_node kernel/fork.c:184 [inline] dup_task_struct+0x57/0x9a0 kernel/fork.c:915 copy_process+0x4ea/0x3950 kernel/fork.c:2052 kernel_clone+0x21e/0x820 kernel/fork.c:2651 user_mode_thread+0xdd/0x140 kernel/fork.c:2727 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:171 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 page_owner free stack trace missing Memory state around the buggy address: ffff8880006a5700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880006a5780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880006a5800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880006a5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880006a5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================