SYS-OSS/FRET-qemu
4
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

block: Fix integer promotion error in bdrv_getlength()

Browse Source 
Back in 2015, we attempted to fix error reporting for images that
claimed to have more than INT64_MAX/512 sectors, but due to the type
promotions caused by BDRV_SECTOR_SIZE being unsigned, this
inadvertently forces all negative ret values to be slammed into -EFBIG
rather than the original error.  While we're at it, we can avoid the
confusing ?: by spelling the logic more directly.

Fixes: 4a9c9ea0d3
Reported-by: Guoyi Tu <tu.guoyi@h3c.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201105155122.60943-1-eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Eric Blake 2020-11-05 09:51:22 -06:00 committed by Max Reitz
parent 7c5c538306
commit 122860bae7
1 changed files with 7 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
block.c
View File

@ -5091,8 +5091,13 @@ int64_t bdrv_getlength(BlockDriverState *bs)
{ {
int64_t ret = bdrv_nb_sectors(bs); int64_t ret = bdrv_nb_sectors(bs);
ret = ret > INT64_MAX / BDRV_SECTOR_SIZE ? -EFBIG : ret; if (ret < 0) {
return ret < 0 ? ret : ret * BDRV_SECTOR_SIZE; return ret;
}
if (ret > INT64_MAX / BDRV_SECTOR_SIZE) {
return -EFBIG;
}
return ret * BDRV_SECTOR_SIZE;
} }
/* return 0 as number of sectors if no device present or error */ /* return 0 as number of sectors if no device present or error */