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authorKevin Wolf <kwolf@redhat.com>2017-07-03 17:07:35 +0200
committerKevin Wolf <kwolf@redhat.com>2017-09-26 14:46:23 +0200
commit3045025991ebeec77ce89c8ec56e83858950bbb3 (patch)
treec5f59bfa82fa3263874f84a1fd9668770b41bd74 /block.c
parent1857c97b76af02537b954c86dab066503950a4fd (diff)
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block: Fix permissions after bdrv_reopen()
If we switch between read-only and read-write, the permissions that image format drivers need on bs->file change, too. Make sure to update the permissions during bdrv_reopen(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
Diffstat (limited to 'block.c')
-rw-r--r--block.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/block.c b/block.c
index 204cbb4..5c65fac 100644
--- a/block.c
+++ b/block.c
@@ -2781,6 +2781,10 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
bs_entry->state.explicit_options = explicit_options;
bs_entry->state.flags = flags;
+ /* This needs to be overwritten in bdrv_reopen_prepare() */
+ bs_entry->state.perm = UINT64_MAX;
+ bs_entry->state.shared_perm = 0;
+
QLIST_FOREACH(child, &bs->children, next) {
QDict *new_child_options;
char *child_key_dot;
@@ -2887,6 +2891,52 @@ int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
return ret;
}
+static BlockReopenQueueEntry *find_parent_in_reopen_queue(BlockReopenQueue *q,
+ BdrvChild *c)
+{
+ BlockReopenQueueEntry *entry;
+
+ QSIMPLEQ_FOREACH(entry, q, entry) {
+ BlockDriverState *bs = entry->state.bs;
+ BdrvChild *child;
+
+ QLIST_FOREACH(child, &bs->children, next) {
+ if (child == c) {
+ return entry;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+static void bdrv_reopen_perm(BlockReopenQueue *q, BlockDriverState *bs,
+ uint64_t *perm, uint64_t *shared)
+{
+ BdrvChild *c;
+ BlockReopenQueueEntry *parent;
+ uint64_t cumulative_perms = 0;
+ uint64_t cumulative_shared_perms = BLK_PERM_ALL;
+
+ QLIST_FOREACH(c, &bs->parents, next_parent) {
+ parent = find_parent_in_reopen_queue(q, c);
+ if (!parent) {
+ cumulative_perms |= c->perm;
+ cumulative_shared_perms &= c->shared_perm;
+ } else {
+ uint64_t nperm, nshared;
+
+ bdrv_child_perm(parent->state.bs, bs, c, c->role, q,
+ parent->state.perm, parent->state.shared_perm,
+ &nperm, &nshared);
+
+ cumulative_perms |= nperm;
+ cumulative_shared_perms &= nshared;
+ }
+ }
+ *perm = cumulative_perms;
+ *shared = cumulative_shared_perms;
+}
/*
* Prepares a BlockDriverState for reopen. All changes are staged in the
@@ -2952,6 +3002,9 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
goto error;
}
+ /* Calculate required permissions after reopening */
+ bdrv_reopen_perm(queue, reopen_state->bs,
+ &reopen_state->perm, &reopen_state->shared_perm);
ret = bdrv_flush(reopen_state->bs);
if (ret) {
@@ -3007,6 +3060,12 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
} while ((entry = qdict_next(reopen_state->options, entry)));
}
+ ret = bdrv_check_perm(reopen_state->bs, queue, reopen_state->perm,
+ reopen_state->shared_perm, NULL, errp);
+ if (ret < 0) {
+ goto error;
+ }
+
ret = 0;
error:
@@ -3047,6 +3106,9 @@ void bdrv_reopen_commit(BDRVReopenState *reopen_state)
bdrv_refresh_limits(bs, NULL);
+ bdrv_set_perm(reopen_state->bs, reopen_state->perm,
+ reopen_state->shared_perm);
+
new_can_write =
!bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE);
if (!old_can_write && new_can_write && drv->bdrv_reopen_bitmaps_rw) {
@@ -3080,6 +3142,8 @@ void bdrv_reopen_abort(BDRVReopenState *reopen_state)
}
QDECREF(reopen_state->explicit_options);
+
+ bdrv_abort_perm_update(reopen_state->bs);
}