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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, Dec 1, 2025 at 12:05=E2=80=AFPM Amir Goldstein = wrote: > > On Mon, Dec 1, 2025 at 10:08=E2=80=AFAM Aleksandr Nogikh wrote: > > > > On Mon, Dec 1, 2025 at 9:58=E2=80=AFAM Amir Goldstein wrote: > > > > > > On Sat, Nov 29, 2025 at 2:05=E2=80=AFPM syzbot > > > wrote: > > > > > > > > Hello, > > > > > > > > syzbot found the following issue on: > > > > > > > > HEAD commit: 7d31f578f323 Add linux-next specific files for 2025= 1128 > > > > git tree: linux-next > > > > console output: https://syzkaller.appspot.com/x/log.txt?x=3D14db5f4= 2580000 > > > > kernel config: https://syzkaller.appspot.com/x/.config?x=3D6336d8e= 94a7c517d > > > > dashboard link: https://syzkaller.appspot.com/bug?extid=3Db74150fd2= ef40e716ca2 > > > > compiler: Debian clang version 20.1.8 (++20250708063551+0c9f9= 09b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 > > > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=3D1780a= 112580000 > > > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=3D10f6be9= 2580000 > > > > > > > > Downloadable assets: > > > > disk image: https://storage.googleapis.com/syzbot-assets/6b49d8ad90= de/disk-7d31f578.raw.xz > > > > vmlinux: https://storage.googleapis.com/syzbot-assets/dbe2d4988ca7/= vmlinux-7d31f578.xz > > > > kernel image: https://storage.googleapis.com/syzbot-assets/fc0448ab= 2411/bzImage-7d31f578.xz > > > > > > > > IMPORTANT: if you fix the issue, please add the following tag to th= e commit: > > > > Reported-by: syzbot+b74150fd2ef40e716ca2@syzkaller.appspotmail.com > > > > > > > > ------------[ cut here ]------------ > > > > WARNING: fs/dcache.c:829 at fast_dput+0x334/0x430 fs/dcache.c:829, = CPU#1: syz.0.17/6053 > > > > Modules linked in: > > > > CPU: 1 UID: 0 PID: 6053 Comm: syz.0.17 Not tainted syzkaller #0 PRE= EMPT(full) > > > > Hardware name: Google Google Compute Engine/Google Compute Engine, = BIOS Google 10/25/2025 > > > > RIP: 0010:fast_dput+0x334/0x430 fs/dcache.c:829 > > > > Code: e3 81 ff 48 b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c= 0 0f 85 e2 00 00 00 41 80 0e 40 e9 fd fe ff ff e8 4d e3 81 ff 90 <0f> 0b 90= e9 ef fe ff ff 44 89 e6 81 e6 00 00 04 00 31 ff e8 74 e7 > > > > RSP: 0018:ffffc90003407cd8 EFLAGS: 00010293 > > > > RAX: ffffffff823fcfe3 RBX: ffff88806c44ac78 RCX: ffff88802e41bd00 > > > > RDX: 0000000000000000 RSI: 00000000ffffff80 RDI: 0000000000000001 > > > > RBP: 00000000ffffff80 R08: 0000000000000003 R09: 0000000000000004 > > > > R10: dffffc0000000000 R11: fffff52000680f8c R12: dffffc0000000000 > > > > R13: 1ffff1100d889597 R14: ffff88806c44abc0 R15: ffff88806c44acb8 > > > > FS: 00005555820e4500(0000) GS:ffff888125f4f000(0000) knlGS:0000000= 000000000 > > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > > CR2: 0000001b31b63fff CR3: 0000000072c78000 CR4: 00000000003526f0 > > > > Call Trace: > > > > > > > > dput+0xe8/0x1a0 fs/dcache.c:924 > > > > __fput+0x68e/0xa70 fs/file_table.c:476 > > > > task_work_run+0x1d4/0x260 kernel/task_work.c:233 > > > > resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] > > > > __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] > > > > exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 > > > > __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [= inline] > > > > syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h= :256 [inline] > > > > syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [i= nline] > > > > syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline= ] > > > > do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 > > > > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > > > RIP: 0033:0x7f4966f8f749 > > > > Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 4= 8 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:00007ffc01c51258 EFLAGS: 00000246 ORIG_RAX: 0000000000000= 1b4 > > > > RAX: 0000000000000000 RBX: 000000000001a7a1 RCX: 00007f4966f8f749 > > > > RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 > > > > RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000201c5154f > > > > R10: 0000001b30f20000 R11: 0000000000000246 R12: 00007f49671e5fac > > > > R13: 00007f49671e5fa0 R14: ffffffffffffffff R15: 0000000000000004 > > > > > > > > > > > > > > Any idea why this was tagged as overlayfs? > > > I do not see overlayfs anywhere in the repro, logs, or stack trace. > > > > Looks like the crash title is too generic, so we ended up with a > > collection of unrelated crashes here. However, several issues are > > indeed related to overlayfs: > > https://syzkaller.appspot.com/text?tag=3DCrashReport&x=3D143464b4580000 > > https://syzkaller.appspot.com/text?tag=3DCrashReport&x=3D1683a112580000 > > > > OK but which repo, if any, are those crashes related to? > I am not exactly sure how to process this information. See the crashes at "2025/11/28 23:23" and at "2025/11/29 06:18" at the bottom of the page here: https://syzkaller.appspot.com/bug?extid=3Db74150fd2ef40e716ca2 Both were found on next-20251128. > > Thanks, > Amir.