sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size sysv_free_block: flc_count > flc_size ================================================================== BUG: KASAN: use-after-free in sysv_new_block+0x7b7/0xa60 fs/sysv/balloc.c:113 Read of size 4 at addr ffff888067d9e0c8 by task syz-executor.0/5935 CPU: 0 PID: 5935 Comm: syz-executor.0 Not tainted 6.5.0-syzkaller-12728-ga48fa7efaf11 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 sysv_new_block+0x7b7/0xa60 fs/sysv/balloc.c:113 alloc_branch fs/sysv/itree.c:134 [inline] get_block+0x279/0x14f0 fs/sysv/itree.c:255 __block_write_begin_int+0x3c0/0x1470 fs/buffer.c:2107 __block_write_begin fs/buffer.c:2157 [inline] block_write_begin+0xb1/0x490 fs/buffer.c:2216 sysv_write_begin+0x31/0xd0 fs/sysv/itree.c:490 generic_perform_write+0x278/0x600 mm/filemap.c:3942 __generic_file_write_iter+0x1f9/0x240 mm/filemap.c:4037 generic_file_write_iter+0xe3/0x350 mm/filemap.c:4063 call_write_iter include/linux/fs.h:1985 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x650/0xe40 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f21e327cb29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f21e401e0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f21e339bf80 RCX: 00007f21e327cb29 RDX: 00000000fffffe45 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00007f21e32c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f21e339bf80 R15: 00007ffef9220168 The buggy address belongs to the physical page: page:ffffea00019f6780 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x67d9e flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 ffffea0001be4f48 ffffea0001be6708 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 5880, tgid 5880 (dhcpcd-run-hook), ts 113997733784, free_ts 114441946776 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 __folio_alloc+0x16/0x40 mm/page_alloc.c:4458 vma_alloc_folio+0x156/0x890 mm/mempolicy.c:2259 do_anonymous_page mm/memory.c:4110 [inline] do_pte_missing mm/memory.c:3667 [inline] handle_pte_fault mm/memory.c:4978 [inline] __handle_mm_fault+0xe6c/0x3e20 mm/memory.c:5119 handle_mm_fault+0x47a/0xa00 mm/memory.c:5284 do_user_addr_fault+0x30b/0x1010 arch/x86/mm/fault.c:1364 handle_page_fault arch/x86/mm/fault.c:1505 [inline] exc_page_fault+0x5c/0xd0 arch/x86/mm/fault.c:1561 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page_list+0xe6/0xb30 mm/page_alloc.c:2451 release_pages+0x32a/0x14e0 mm/swap.c:1042 tlb_batch_pages_flush+0x9a/0x190 mm/mmu_gather.c:98 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] tlb_flush_mmu mm/mmu_gather.c:300 [inline] tlb_finish_mmu+0x14b/0x6f0 mm/mmu_gather.c:392 exit_mmap+0x38b/0xa60 mm/mmap.c:3223 __mmput+0x12a/0x4d0 kernel/fork.c:1349 mmput+0x62/0x70 kernel/fork.c:1371 exit_mm kernel/exit.c:567 [inline] do_exit+0x9b4/0x2a20 kernel/exit.c:861 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888067d9df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888067d9e000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888067d9e080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888067d9e100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888067d9e180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================