attempt to access beyond end of device loop1: rw=0, want=6491538, limit=128 Buffer I/O error on dev loop1, logical block 3245768, async page read unable to read i-node block ================================================================== BUG: KASAN: use-after-free in sysv_new_block+0x788/0x960 fs/sysv/balloc.c:113 Read of size 4 at addr ffff8880683af0c8 by task syz.1.7/4255 CPU: 1 PID: 4255 Comm: syz.1.7 Not tainted 5.15.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 sysv_new_block+0x788/0x960 fs/sysv/balloc.c:113 alloc_branch fs/sysv/itree.c:134 [inline] get_block+0x2e7/0x1790 fs/sysv/itree.c:253 __block_write_begin_int+0x60b/0x1650 fs/buffer.c:2012 __block_write_begin fs/buffer.c:2062 [inline] block_write_begin+0x4f/0xc0 fs/buffer.c:2122 sysv_write_begin+0x36/0x70 fs/sysv/itree.c:487 __page_symlink+0x15b/0x2a0 fs/namei.c:5177 sysv_symlink+0xcb/0x180 fs/sysv/namei.c:86 vfs_symlink+0x247/0x3d0 fs/namei.c:4429 do_symlinkat+0x1fd/0x600 fs/namei.c:4458 __do_sys_symlink fs/namei.c:4480 [inline] __se_sys_symlink fs/namei.c:4478 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4478 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f88c295ad29 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:00007f88c07cb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 00007f88c2b4afa0 RCX: 00007f88c295ad29 RDX: 0000000000000000 RSI: 00000000200059c0 RDI: 0000000020002840 RBP: 00007f88c29d6b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f88c2b4afa0 R15: 00007fff8d899ca8 The buggy address belongs to the page: page:ffffea0001a0ebc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x683af flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001a0ec08 ffffea0001a0eb88 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 0x8(__GFP_MOVABLE), pid 1, ts 18654444869, free_ts 19772879509 split_map_pages+0x246/0x510 mm/compaction.c:99 isolate_freepages_range+0x47c/0x4e0 mm/compaction.c:749 alloc_contig_range+0xc2b/0xf90 mm/page_alloc.c:9258 __alloc_contig_pages mm/page_alloc.c:9282 [inline] alloc_contig_pages+0x3ea/0x4e0 mm/page_alloc.c:9362 debug_vm_pgtable_alloc_huge_page+0xb9/0x110 mm/debug_vm_pgtable.c:1085 init_args+0xc62/0xf50 mm/debug_vm_pgtable.c:1207 debug_vm_pgtable+0xaa/0x470 mm/debug_vm_pgtable.c:1245 do_one_initcall+0x22b/0x7a0 init/main.c:1302 do_initcall_level+0x157/0x210 init/main.c:1375 do_initcalls+0x49/0x90 init/main.c:1391 kernel_init_freeable+0x425/0x5c0 init/main.c:1615 kernel_init+0x19/0x290 init/main.c:1506 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396 free_contig_range+0x95/0xf0 mm/page_alloc.c:9384 destroy_args+0xfe/0x980 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x40d/0x470 mm/debug_vm_pgtable.c:1331 do_one_initcall+0x22b/0x7a0 init/main.c:1302 do_initcall_level+0x157/0x210 init/main.c:1375 do_initcalls+0x49/0x90 init/main.c:1391 kernel_init_freeable+0x425/0x5c0 init/main.c:1615 kernel_init+0x19/0x290 init/main.c:1506 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff8880683aef80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880683af000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880683af080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880683af100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880683af180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================