On Thu, Feb 6, 2025 at 2:32 PM syzbot <syzbot+62dfea789a2cedac1298@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 808eb958781e Add linux-next specific files for 20250206 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=126e33df980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=88b25e5d30d576e4 > dashboard link: https://syzkaller.appspot.com/bug?extid=62dfea789a2cedac1298 > 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=16346df8580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=117e80e4580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/493ef93f2e5f/disk-808eb958.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/b41757cd41c9/vmlinux-808eb958.xz > kernel image: https://storage.googleapis.com/syzbot-assets/24f456104aad/bzImage-808eb958.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+62dfea789a2cedac1298@xxxxxxxxxxxxxxxxxxxxxxxxx > > Oops: general protection fault, probably for non-canonical address 0xdffffc0000000009: 0000 [#1] PREEMPT SMP KASAN PTI > KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f] > CPU: 0 UID: 0 PID: 5834 Comm: syz-executor772 Not tainted 6.14.0-rc1-next-20250206-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 > RIP: 0010:is_anon_ns fs/mount.h:159 [inline] > RIP: 0010:clone_private_mount+0x184/0x3e0 fs/namespace.c:2425 Christian, This obviously points to line: /* Make sure this isn't something purely kernel internal. */ if (!is_anon_ns(old_mnt->mnt_ns)) in commit: ae63304102ecd fs: allow detached mounts in clone_private_mount() Where old_mnt->mnt_ns can be NULL. Thanks, Amir.
