> On 7/18/24 02:20, syzbot wrote: >> Hello, >> >> syzbot found the following issue on: >> >> HEAD commit: d67978318827 Merge tag 'x86_cpu_for_v6.11_rc1' of git://gi.. >> git tree: upstream >> console+strace: https://syzkaller.appspot.com/x/log.txt?x=1178e9e9980000 >> kernel config: https://syzkaller.appspot.com/x/.config?x=e206d588252bd3ff >> dashboard link: https://syzkaller.appspot.com/bug?extid=2074b1a3d447915c6f1c >> 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=10e07d9e980000 >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16adf045980000 >> >> Downloadable assets: >> disk image: https://storage.googleapis.com/syzbot-assets/f34b31760156/disk-d6797831.raw.xz >> vmlinux: https://storage.googleapis.com/syzbot-assets/a92e51d8d32e/vmlinux-d6797831.xz >> kernel image: https://storage.googleapis.com/syzbot-assets/000a6a162550/bzImage-d6797831.xz >> >> The issue was bisected to: >> >> commit 87585b05757dc70545efb434669708d276125559 >> Author: Jens Axboe <axboe@xxxxxxxxx> >> Date: Wed Mar 13 02:24:21 2024 +0000 >> >> io_uring/kbuf: use vm_insert_pages() for mmap'ed pbuf ring > Easily reproducible, the diff helps > > #syz test: want either no args or 2 args (repo, branch), got 4 > > > diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c > index d2945c9c812b..c95dc1736dd9 100644 > --- a/io_uring/kbuf.c > +++ b/io_uring/kbuf.c > @@ -657,8 +657,10 @@ static int io_alloc_pbuf_ring(struct io_ring_ctx *ctx, > ring_size = reg->ring_entries * sizeof(struct io_uring_buf_ring); > > bl->buf_ring = io_pages_map(&bl->buf_pages, &bl->buf_nr_pages, ring_size); > - if (!bl->buf_ring) > + if (IS_ERR(bl->buf_ring)) { > + bl->buf_ring = NULL; > return -ENOMEM; > + } > > bl->is_buf_ring = 1; > bl->is_mmap = 1; >
