Hello, syzbot found the following issue on: HEAD commit: 69e858e0b8b2 Merge tag 'uml-for-linus-6.14-rc1' of git://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17814b24580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d033b14aeef39158 dashboard link: https://syzkaller.appspot.com/bug?extid=a0ae55e3dde11d2d790c compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13877b64580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16063ddf980000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-69e858e0.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/a53b888c1f3f/vmlinux-69e858e0.xz kernel image: https://storage.googleapis.com/syzbot-assets/6b5e17edafc0/bzImage-69e858e0.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/680b2fde83a8/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a0ae55e3dde11d2d790c@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ UBSAN: shift-out-of-bounds in lib/xarray.c:147:16 shift exponent 192 is too large for 64-bit type 'unsigned long' CPU: 0 UID: 0 PID: 2666 Comm: kworker/u4:9 Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: loop0 loop_rootcg_workfn Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468 get_offset lib/xarray.c:147 [inline] xas_descend lib/xarray.c:207 [inline] xas_load+0x583/0x5c0 lib/xarray.c:246 filemap_get_entry+0x1f0/0x3b0 mm/filemap.c:1860 shmem_get_folio_gfp+0x285/0x1840 mm/shmem.c:2446 shmem_get_folio mm/shmem.c:2628 [inline] shmem_write_begin+0x165/0x350 mm/shmem.c:3278 generic_perform_write+0x346/0x990 mm/filemap.c:4189 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3454 do_iter_readv_writev+0x71a/0x9d0 vfs_iter_write+0x23e/0x600 fs/read_write.c:974 lo_write_bvec drivers/block/loop.c:245 [inline] lo_write_simple drivers/block/loop.c:266 [inline] do_req_filebacked drivers/block/loop.c:520 [inline] loop_handle_cmd drivers/block/loop.c:1926 [inline] loop_process_work+0x1429/0x21c0 drivers/block/loop.c:1961 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
