From b87d11b7f13dd4725fe801b014d425fa7753b1d0 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 4 Dec 2017 12:10:05 +0100 Subject: [PATCH 34/36] block: Fix permissions after bdrv_reopen() RH-Author: Kevin Wolf Message-id: <20171204121007.12964-7-kwolf@redhat.com> Patchwork-id: 78112 O-Subject: [RHV-7.5 qemu-kvm-rhev PATCH v2 6/8] block: Fix permissions after bdrv_reopen() Bugzilla: 1492178 RH-Acked-by: Fam Zheng RH-Acked-by: Max Reitz RH-Acked-by: Jeffrey Cody 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 Reviewed-by: Eric Blake (cherry picked from commit 3045025991ebeec77ce89c8ec56e83858950bbb3) Signed-off-by: Miroslav Rezanina --- block.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/block/block.h | 1 + 2 files changed, 65 insertions(+) diff --git a/block.c b/block.c index 0a7e2c6..bc8b80b 100644 --- a/block.c +++ b/block.c @@ -2780,6 +2780,10 @@ 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; @@ -2886,6 +2890,52 @@ 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 @@ -2951,6 +3001,9 @@ 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) { @@ -3006,6 +3059,12 @@ 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: @@ -3046,6 +3105,9 @@ 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) { @@ -3079,6 +3141,8 @@ void bdrv_reopen_abort(BDRVReopenState *reopen_state) } QDECREF(reopen_state->explicit_options); + + bdrv_abort_perm_update(reopen_state->bs); } diff --git a/include/block/block.h b/include/block/block.h index 4d0d2da..59a3077 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -166,6 +166,7 @@ typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; typedef struct BDRVReopenState { BlockDriverState *bs; int flags; + uint64_t perm, shared_perm; QDict *options; QDict *explicit_options; void *opaque; -- 1.8.3.1