loop1: detected capacity change from 0 to 128 VFS: Found a Xenix FS (block size = 1024) on device loop1 ================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0xd28/0xebc fs/sysv/ialloc.c:153 Read of size 2 at addr ffff0000fb9ea1ce by task syz.1.211/7806 CPU: 1 UID: 0 PID: 7806 Comm: syz.1.211 Not tainted 6.14.0-rc7-syzkaller-ga2392f333575 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x198/0x550 mm/kasan/report.c:521 kasan_report+0xd8/0x138 mm/kasan/report.c:634 __asan_report_load2_noabort+0x20/0x2c mm/kasan/report_generic.c:379 sysv_new_inode+0xd28/0xebc fs/sysv/ialloc.c:153 sysv_mknod+0x5c/0x100 fs/sysv/namei.c:53 sysv_create+0x38/0x4c fs/sysv/namei.c:67 lookup_open fs/namei.c:3651 [inline] open_last_lookups fs/namei.c:3750 [inline] path_openat+0x13ec/0x2b1c fs/namei.c:3986 do_filp_open+0x1e8/0x404 fs/namei.c:4016 do_sys_openat2+0x124/0x1b8 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1454 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 The buggy address belongs to the physical page: page: refcount:2 mapcount:1 mapping:00000000000f7489 index:0xa56 pfn:0x13b9ea memcg:ffff0000d50b2000 aops:shmem_aops ino:4a dentry name(?):"dev/zero" flags: 0x5ffc0000002102c(referenced|uptodate|lru|arch_1|swapbacked|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc0000002102c fffffdffc3ee7a48 fffffdffc3ee7ac8 ffff0000f06844f0 raw: 0000000000000a56 0000000000000000 0000000200000000 ffff0000d50b2000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000fb9ea080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000fb9ea100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000fb9ea180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff0000fb9ea200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000fb9ea280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== syz.1.211: attempt to access beyond end of device loop1: rw=2049, sector=6491536, nr_sectors = 2 limit=128 syz.1.211: attempt to access beyond end of device loop1: rw=2049, sector=6491536, nr_sectors = 2 limit=128