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 ================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0x10b4/0x1240 fs/sysv/ialloc.c:153 Read of size 2 at addr ffff888057de31ce by task syz.1.683/7123 CPU: 0 PID: 7123 Comm: syz.1.683 Not tainted 5.15.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 sysv_new_inode+0x10b4/0x1240 fs/sysv/ialloc.c:153 sysv_mknod+0x4a/0xd0 fs/sysv/namei.c:53 lookup_open fs/namei.c:3462 [inline] open_last_lookups fs/namei.c:3532 [inline] path_openat+0x11e1/0x2f30 fs/namei.c:3739 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_creat fs/open.c:1345 [inline] __se_sys_creat fs/open.c:1339 [inline] __x64_sys_creat+0x8c/0xb0 fs/open.c:1339 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fbc810fe969 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:00007fbc7ef66038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fbc81325fa0 RCX: 00007fbc810fe969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040 RBP: 00007fbc81180ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbc81325fa0 R15: 00007fff99204418 The buggy address belongs to the page: page:ffffea00015f78c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x100 pfn:0x57de3 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000100 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 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 6828, ts 248114679170, free_ts 250382098520 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5466 alloc_pages_vma+0x393/0x7c0 mm/mempolicy.c:2146 shmem_alloc_page mm/shmem.c:1586 [inline] shmem_alloc_and_acct_page+0x427/0xb70 mm/shmem.c:1611 shmem_getpage_gfp+0x14f4/0x2d40 mm/shmem.c:1906 shmem_getpage mm/shmem.c:151 [inline] shmem_write_begin+0xcd/0x1a0 mm/shmem.c:2474 generic_perform_write+0x2aa/0x530 mm/filemap.c:3785 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944 __kernel_write+0x4f9/0x930 fs/read_write.c:539 __dump_emit+0x243/0x360 fs/coredump.c:875 dump_user_range+0x84/0x340 fs/coredump.c:949 elf_core_dump+0x2ff7/0x3530 fs/binfmt_elf.c:2285 do_coredump+0x139f/0x28f0 fs/coredump.c:826 get_signal+0x40a/0x12c0 kernel/signal.c:2886 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 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+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page_list+0x122/0x7e0 mm/page_alloc.c:3433 release_pages+0x184b/0x1bb0 mm/swap.c:963 __pagevec_release+0x6d/0xe0 mm/swap.c:983 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x593/0x1840 mm/shmem.c:964 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_evict_inode+0x20d/0xa00 mm/shmem.c:1145 evict+0x485/0x870 fs/inode.c:647 do_unlinkat+0x3d8/0x6f0 fs/namei.c:4355 __do_sys_unlink fs/namei.c:4396 [inline] __se_sys_unlink fs/namei.c:4394 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4394 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff888057de3080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888057de3100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888057de3180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888057de3200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888057de3280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================