On Wed, Mar 13, 2024 at 12:23 PM syzbot <syzbot+3abd99031b42acf367ef@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 707081b61156 Merge branch 'for-next/core', remote-tracking.. > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > console output: https://syzkaller.appspot.com/x/log.txt?x=1785a859180000 > kernel config: https://syzkaller.appspot.com/x/.config?x=caeac3f3565b057a > dashboard link: https://syzkaller.appspot.com/bug?extid=3abd99031b42acf367ef > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > userspace arch: arm64 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1115ada6180000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1626870a180000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/6cad68bf7532/disk-707081b6.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/1a27e5400778/vmlinux-707081b6.xz > kernel image: https://storage.googleapis.com/syzbot-assets/67dfc53755d0/Image-707081b6.gz.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+3abd99031b42acf367ef@xxxxxxxxxxxxxxxxxxxxxxxxx > > evm: overlay not supported > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 6187 at fs/overlayfs/copy_up.c:239 ovl_copy_up_file+0x624/0x674 fs/overlayfs/copy_up.c:330 Miklos, The WARN_ON that I put in ovl_verify_area() may be too harsh. I think they can happen if lower file is changed (i_size) while file is being copied up after reading i_size into the copy length and this could be the case with this syzbot reproducer that keeps mounting overlayfs instances over same path. Should probably demote those WARN_ON to just returning EIO? Thanks, Amir.
