add two more stable patches

[pve-qemu.git] / debian / patches / extra / 0020-io_uring-fix-short-read-slow-path.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Dominique Martinet <dominique.martinet@atmark-techno.com>
Date: Thu, 30 Jun 2022 10:01:37 +0900
Subject: [PATCH] io_uring: fix short read slow path

sqeq.off here is the offset to read within the disk image, so obviously
not 'nread' (the amount we just read), but as the author meant to write
its current value incremented by the amount we just read.

Normally recent versions of linux will not issue short reads,
but it can happen so we should fix this.

This lead to weird image corruptions when short read happened

Fixes: 6663a0a33764 ("block/io_uring: implements interfaces for io_uring")
Link: https://lkml.kernel.org/r/YrrFGO4A1jS0GI0G@atmark-techno.com
Signed-off-by: Dominique Martinet <dominique.martinet@atmark-techno.com>
Message-Id: <20220630010137.2518851-1-dominique.martinet@atmark-techno.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry-picked from commit c06fc7ce147e57ab493bad9263f1601b8298484b)
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
---
 block/io_uring.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/io_uring.c b/block/io_uring.c
index 782afdb433..e451e55de0 100644
--- a/block/io_uring.c
+++ b/block/io_uring.c
@@ -89,7 +89,7 @@ static void luring_resubmit_short_read(LuringState *s, LuringAIOCB *luringcb,
     trace_luring_resubmit_short_read(s, luringcb, nread);
 
     /* Update read position */
-    luringcb->total_read = nread;
+    luringcb->total_read += nread;
     remaining = luringcb->qiov->size - luringcb->total_read;
 
     /* Shorten qiov */
@@ -103,7 +103,7 @@ static void luring_resubmit_short_read(LuringState *s, LuringAIOCB *luringcb,
                       remaining);
 
     /* Update sqe */
-    luringcb->sqeq.off = nread;
+    luringcb->sqeq.off += nread;
     luringcb->sqeq.addr = (__u64)(uintptr_t)luringcb->resubmit_qiov.iov;
     luringcb->sqeq.len = luringcb->resubmit_qiov.niov;