debian/patches/pve/0062-block-alloc-track-avoid-premature-break.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Fabian Ebner <f.ebner@proxmox.com>
   3 Date: Wed, 22 Jun 2022 10:45:13 +0200
   4 Subject: [PATCH] block: alloc-track: avoid premature break
   5
   6 While the bdrv_co_preadv() calls are expected to return 0 on success,
   7 qemu_iovec_memset() will return the number of bytes set (will be
   8 local_bytes, because the slice with that size was just initialized).
   9
  10 Don't break out of the loop after the branch with qemu_iovec_memset(),
  11 because there might still be work to do. Additionally, ret is an int,
  12 which on 64-bit platforms is too small to hold the size_t returned by
  13 qemu_iovec_memset().
  14
  15 The branch seems to be difficult to reach in practice, because the
  16 whole point of alloc-track is to be used with a backing device.
  17
  18 Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
  19 ---
  20  block/alloc-track.c | 3 ++-
  21  1 file changed, 2 insertions(+), 1 deletion(-)
  22
  23 diff --git a/block/alloc-track.c b/block/alloc-track.c
  24 index 6b50fbe537..c1160af04b 100644
  25 --- a/block/alloc-track.c
  26 +++ b/block/alloc-track.c
  27 @@ -174,7 +174,8 @@ static int coroutine_fn track_co_preadv(BlockDriverState *bs,
  28              ret = bdrv_co_preadv(bs->backing, local_offset, local_bytes,
  29                                   &local_qiov, flags);
  30          } else {
  31 -            ret = qemu_iovec_memset(&local_qiov, cur_offset, 0, local_bytes);
  32 +            qemu_iovec_memset(&local_qiov, cur_offset, 0, local_bytes);
  33 +            ret = 0;
  34          }
  35
  36          if (ret != 0) {