debian/patches/extra/0020-io_uring-fix-short-read-slow-path.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Dominique Martinet <dominique.martinet@atmark-techno.com>
   3 Date: Thu, 30 Jun 2022 10:01:37 +0900
   4 Subject: [PATCH] io_uring: fix short read slow path
   5
   6 sqeq.off here is the offset to read within the disk image, so obviously
   7 not 'nread' (the amount we just read), but as the author meant to write
   8 its current value incremented by the amount we just read.
   9
  10 Normally recent versions of linux will not issue short reads,
  11 but it can happen so we should fix this.
  12
  13 This lead to weird image corruptions when short read happened
  14
  15 Fixes: 6663a0a33764 ("block/io_uring: implements interfaces for io_uring")
  16 Link: https://lkml.kernel.org/r/YrrFGO4A1jS0GI0G@atmark-techno.com
  17 Signed-off-by: Dominique Martinet <dominique.martinet@atmark-techno.com>
  18 Message-Id: <20220630010137.2518851-1-dominique.martinet@atmark-techno.com>
  19 Reviewed-by: Hanna Reitz <hreitz@redhat.com>
  20 Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
  21 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
  22 (cherry-picked from commit c06fc7ce147e57ab493bad9263f1601b8298484b)
  23 Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
  24 ---
  25  block/io_uring.c | 4 ++--
  26  1 file changed, 2 insertions(+), 2 deletions(-)
  27
  28 diff --git a/block/io_uring.c b/block/io_uring.c
  29 index 782afdb433..e451e55de0 100644
  30 --- a/block/io_uring.c
  31 +++ b/block/io_uring.c
  32 @@ -89,7 +89,7 @@ static void luring_resubmit_short_read(LuringState *s, LuringAIOCB *luringcb,
  33      trace_luring_resubmit_short_read(s, luringcb, nread);
  34
  35      /* Update read position */
  36 -    luringcb->total_read = nread;
  37 +    luringcb->total_read += nread;
  38      remaining = luringcb->qiov->size - luringcb->total_read;
  39
  40      /* Shorten qiov */
  41 @@ -103,7 +103,7 @@ static void luring_resubmit_short_read(LuringState *s, LuringAIOCB *luringcb,
  42                        remaining);
  43
  44      /* Update sqe */
  45 -    luringcb->sqeq.off = nread;
  46 +    luringcb->sqeq.off += nread;
  47      luringcb->sqeq.addr = (__u64)(uintptr_t)luringcb->resubmit_qiov.iov;
  48      luringcb->sqeq.len = luringcb->resubmit_qiov.niov;
  49