Buffer I/O error on dev loop2, logical block 3245768, async page read ================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0x107e/0x1210 fs/sysv/ialloc.c:153 Read of size 2 at addr ffff8880706f61ce by task syz.2.14/4402 CPU: 1 PID: 4402 Comm: syz.2.14 Not tainted 6.1.118-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+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 sysv_new_inode+0x107e/0x1210 fs/sysv/ialloc.c:153 sysv_mknod+0x4a/0xe0 fs/sysv/namei.c:53 vfs_mknod+0x444/0x4d0 fs/namei.c:3985 do_mknodat+0x3f8/0x5a0 __do_sys_mknodat fs/namei.c:4063 [inline] __se_sys_mknodat fs/namei.c:4060 [inline] __x64_sys_mknodat+0xa5/0xc0 fs/namei.c:4060 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff9f937e819 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:00007ff9fa1e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000103 RAX: ffffffffffffffda RBX: 00007ff9f9535fa0 RCX: 00007ff9f937e819 RDX: b0a54e68b1cd2fdb RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 00007ff9f93f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000103 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff9f9535fa0 R15: 00007ffcd7e00f98 The buggy address belongs to the physical page: page:ffffea0001c1bd80 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x706f6 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001c1bdc8 ffffea0001466108 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 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 4343, tgid 4341 (syz.3.4), ts 68318681409, free_ts 69631008024 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517 prep_new_page mm/page_alloc.c:2524 [inline] get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5589 __folio_alloc+0xf/0x30 mm/page_alloc.c:5621 vma_alloc_folio+0x486/0x990 mm/mempolicy.c:2243 shmem_alloc_folio mm/shmem.c:1591 [inline] shmem_alloc_and_acct_folio+0x5a8/0xd50 mm/shmem.c:1615 shmem_get_folio_gfp+0x13f0/0x3470 mm/shmem.c:1943 shmem_get_folio mm/shmem.c:2074 [inline] shmem_write_begin+0x16e/0x4e0 mm/shmem.c:2561 generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3845 __generic_file_write_iter+0x176/0x400 mm/filemap.c:3973 generic_file_write_iter+0xab/0x310 mm/filemap.c:4005 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x857/0xbc0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1444 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3510 release_pages+0x2836/0x2b40 mm/swap.c:1055 __pagevec_release+0x80/0xf0 mm/swap.c:1075 pagevec_release include/linux/pagevec.h:71 [inline] folio_batch_release include/linux/pagevec.h:135 [inline] shmem_undo_range+0x865/0x2390 mm/shmem.c:946 shmem_truncate_range mm/shmem.c:1062 [inline] shmem_evict_inode+0x265/0xa60 mm/shmem.c:1173 evict+0x529/0x930 fs/inode.c:701 __dentry_kill+0x436/0x650 fs/dcache.c:611 dentry_kill+0xbb/0x290 dput+0xfb/0x1d0 fs/dcache.c:918 __fput+0x62e/0x8d0 fs/file_table.c:328 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 Memory state around the buggy address: ffff8880706f6080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880706f6100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880706f6180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880706f6200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880706f6280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================