openkylin
/
qemu
mirror of https://gitee.com/openkylin/qemu.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

block/file-posix: do not fail on unlock bytes 

bdrv_replace_child() calls bdrv_check_perm() with error_abort on
loosening permissions. However file-locking operations may fail even
in this case, for example on NFS. And this leads to Qemu crash.

Let's avoid such errors. Note, that we ignore such things anyway on
permission update commit and abort.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2019-03-29 14:04:54 +03:00 committed by Kevin Wolf
parent 38e694fcc9
commit 696aaaed57
1 changed files with 12 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
block/file-posix.c
View File

@ -815,6 +815,18 @@ static int raw_handle_perm_lock(BlockDriverState *bs,
switch (op) {
case RAW_PL_PREPARE:
if ((s->perm | new_perm) == s->perm &&
(s->shared_perm & new_shared) == s->shared_perm)
{
/*
* We are going to unlock bytes, it should not fail. If it fail due
* to some fs-dependent permission-unrelated reasons (which occurs
* sometimes on NFS and leads to abort in bdrv_replace_child) we
* can't prevent such errors by any check here. And we ignore them
* anyway in ABORT and COMMIT.
*/
return 0;
}
ret = raw_apply_lock_bytes(s, s->fd, s->perm | new_perm,
~s->shared_perm | ~new_shared,
false, errp);