From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Date: Wed, 6 Oct 2021 13:17:18 +0000 (+0200)
Subject: block-backend: drop INT_MAX restriction from blk_check_byte_request()
X-Git-Tag: v6.2.0-rc0~52^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=aa78b825162163d2c51903490d67c10a689eac6b;p=thirdparty%2Fqemu.git

block-backend: drop INT_MAX restriction from blk_check_byte_request()

blk_check_bytes_request is called from blk_co_do_preadv,
blk_co_do_pwritev_part, blk_co_do_pdiscard and blk_co_copy_range
before (maybe) calling throttle_group_co_io_limits_intercept() (which
has int64_t argument) and then calling corresponding bdrv_co_ function.
bdrv_co_ functions are OK with int64_t bytes as well.

So dropping the check for INT_MAX we just get same restrictions as in
bdrv_ layer: discard and write-zeroes goes through
bdrv_check_qiov_request() and are allowed to be 64bit. Other requests
go through bdrv_check_request32() and still restricted by INT_MAX
boundary.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20211006131718.214235-13-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---

diff --git a/block/block-backend.c b/block/block-backend.c
index 59746eda45b..39cd99df2b3 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1166,7 +1166,7 @@ static int blk_check_byte_request(BlockBackend *blk, int64_t offset,
 {
     int64_t len;
 
-    if (bytes < 0 || bytes > INT_MAX) {
+    if (bytes < 0) {
         return -EIO;
     }