diff options
Diffstat (limited to '0118-tools-xenstore-remove-nodes-owned-by-destroyed-domai.patch')
| -rw-r--r-- | 0118-tools-xenstore-remove-nodes-owned-by-destroyed-domai.patch | 299 |
1 files changed, 0 insertions, 299 deletions
diff --git a/0118-tools-xenstore-remove-nodes-owned-by-destroyed-domai.patch b/0118-tools-xenstore-remove-nodes-owned-by-destroyed-domai.patch deleted file mode 100644 index a95a48e..0000000 --- a/0118-tools-xenstore-remove-nodes-owned-by-destroyed-domai.patch +++ /dev/null @@ -1,299 +0,0 @@ -From da87661d058c4a6cf2ea6439771b9834f1c06223 Mon Sep 17 00:00:00 2001 -From: Juergen Gross <jgross@suse.com> -Date: Tue, 13 Sep 2022 07:35:12 +0200 -Subject: [PATCH 118/126] tools/xenstore: remove nodes owned by destroyed - domain - -In case a domain is removed from Xenstore, remove all nodes owned by -it per default. - -This tackles the problem that nodes might be created by a domain -outside its home path in Xenstore, leading to Xenstore hogging more -and more memory. Domain quota don't work in this case if the guest is -rebooting in between. - -Since XSA-322 ownership of such stale nodes is transferred to dom0, -which is helping against unintended access, but not against OOM of -Xenstore. - -As a fallback for weird cases add a Xenstore start parameter for -keeping today's way to handle stale nodes, adding the risk of Xenstore -hitting an OOM situation. - -This is part of XSA-419 / CVE-2022-42322. - -Fixes: 496306324d8d ("tools/xenstore: revoke access rights for removed domains") -Signed-off-by: Juergen Gross <jgross@suse.com> -Reviewed-by: Julien Grall <jgrall@amazon.com> -(cherry picked from commit 755d3f9debf8879448211fffb018f556136f6a79) ---- - tools/xenstore/xenstored_core.c | 17 +++++-- - tools/xenstore/xenstored_core.h | 4 ++ - tools/xenstore/xenstored_domain.c | 84 +++++++++++++++++++++++-------- - tools/xenstore/xenstored_domain.h | 2 +- - 4 files changed, 80 insertions(+), 27 deletions(-) - -diff --git a/tools/xenstore/xenstored_core.c b/tools/xenstore/xenstored_core.c -index e8cdfeef50c7..d5b2e59b0db6 100644 ---- a/tools/xenstore/xenstored_core.c -+++ b/tools/xenstore/xenstored_core.c -@@ -80,6 +80,7 @@ static bool verbose = false; - LIST_HEAD(connections); - int tracefd = -1; - static bool recovery = true; -+bool keep_orphans = false; - static int reopen_log_pipe[2]; - static int reopen_log_pipe0_pollfd_idx = -1; - char *tracefile = NULL; -@@ -722,7 +723,7 @@ struct node *read_node(struct connection *conn, const void *ctx, - node->perms.p = hdr->perms; - node->acc.domid = node->perms.p[0].id; - node->acc.memory = data.dsize; -- if (domain_adjust_node_perms(conn, node)) -+ if (domain_adjust_node_perms(node)) - goto error; - - /* If owner is gone reset currently accounted memory size. */ -@@ -765,7 +766,7 @@ int write_node_raw(struct connection *conn, TDB_DATA *key, struct node *node, - void *p; - struct xs_tdb_record_hdr *hdr; - -- if (domain_adjust_node_perms(conn, node)) -+ if (domain_adjust_node_perms(node)) - return errno; - - data.dsize = sizeof(*hdr) -@@ -1617,7 +1618,7 @@ static int delnode_sub(const void *ctx, struct connection *conn, - return WALK_TREE_RM_CHILDENTRY; - } - --static int _rm(struct connection *conn, const void *ctx, const char *name) -+int rm_node(struct connection *conn, const void *ctx, const char *name) - { - struct node *parent; - char *parentname = get_parent(ctx, name); -@@ -1681,7 +1682,7 @@ static int do_rm(const void *ctx, struct connection *conn, - if (streq(name, "/")) - return EINVAL; - -- ret = _rm(conn, ctx, name); -+ ret = rm_node(conn, ctx, name); - if (ret) - return ret; - -@@ -2537,6 +2538,8 @@ static void usage(void) - " -R, --no-recovery to request that no recovery should be attempted when\n" - " the store is corrupted (debug only),\n" - " -I, --internal-db store database in memory, not on disk\n" -+" -K, --keep-orphans don't delete nodes owned by a domain when the\n" -+" domain is deleted (this is a security risk!)\n" - " -V, --verbose to request verbose execution.\n"); - } - -@@ -2561,6 +2564,7 @@ static struct option options[] = { - { "timeout", 1, NULL, 'w' }, - { "no-recovery", 0, NULL, 'R' }, - { "internal-db", 0, NULL, 'I' }, -+ { "keep-orphans", 0, NULL, 'K' }, - { "verbose", 0, NULL, 'V' }, - { "watch-nb", 1, NULL, 'W' }, - #ifndef NO_LIVE_UPDATE -@@ -2641,7 +2645,7 @@ int main(int argc, char *argv[]) - orig_argc = argc; - orig_argv = argv; - -- while ((opt = getopt_long(argc, argv, "DE:F:HNPS:t:A:M:Q:q:T:RVW:w:U", -+ while ((opt = getopt_long(argc, argv, "DE:F:HKNPS:t:A:M:Q:q:T:RVW:w:U", - options, NULL)) != -1) { - switch (opt) { - case 'D': -@@ -2677,6 +2681,9 @@ int main(int argc, char *argv[]) - case 'I': - tdb_flags = TDB_INTERNAL|TDB_NOLOCK; - break; -+ case 'K': -+ keep_orphans = true; -+ break; - case 'V': - verbose = true; - break; -diff --git a/tools/xenstore/xenstored_core.h b/tools/xenstore/xenstored_core.h -index 3190494bbeb5..9a9dbb2c3c86 100644 ---- a/tools/xenstore/xenstored_core.h -+++ b/tools/xenstore/xenstored_core.h -@@ -233,6 +233,9 @@ int write_node_raw(struct connection *conn, TDB_DATA *key, struct node *node, - struct node *read_node(struct connection *conn, const void *ctx, - const char *name); - -+/* Remove a node and its children. */ -+int rm_node(struct connection *conn, const void *ctx, const char *name); -+ - void setup_structure(bool live_update); - struct connection *new_connection(connwritefn_t *write, connreadfn_t *read); - struct connection *get_connection_by_id(unsigned int conn_id); -@@ -279,6 +282,7 @@ extern int quota_req_outstanding; - extern int quota_trans_nodes; - extern int quota_memory_per_domain_soft; - extern int quota_memory_per_domain_hard; -+extern bool keep_orphans; - - extern unsigned int timeout_watch_event_msec; - -diff --git a/tools/xenstore/xenstored_domain.c b/tools/xenstore/xenstored_domain.c -index a91cc75ab59b..ee4b19387db8 100644 ---- a/tools/xenstore/xenstored_domain.c -+++ b/tools/xenstore/xenstored_domain.c -@@ -196,10 +196,64 @@ static void unmap_interface(void *interface) - xengnttab_unmap(*xgt_handle, interface, 1); - } - -+static int domain_tree_remove_sub(const void *ctx, struct connection *conn, -+ struct node *node, void *arg) -+{ -+ struct domain *domain = arg; -+ TDB_DATA key; -+ int ret = WALK_TREE_OK; -+ -+ if (node->perms.p[0].id != domain->domid) -+ return WALK_TREE_OK; -+ -+ if (keep_orphans) { -+ set_tdb_key(node->name, &key); -+ domain->nbentry--; -+ node->perms.p[0].id = priv_domid; -+ node->acc.memory = 0; -+ domain_entry_inc(NULL, node); -+ if (write_node_raw(NULL, &key, node, true)) { -+ /* That's unfortunate. We only can try to continue. */ -+ syslog(LOG_ERR, -+ "error when moving orphaned node %s to dom0\n", -+ node->name); -+ } else -+ trace("orphaned node %s moved to dom0\n", node->name); -+ } else { -+ if (rm_node(NULL, ctx, node->name)) { -+ /* That's unfortunate. We only can try to continue. */ -+ syslog(LOG_ERR, -+ "error when deleting orphaned node %s\n", -+ node->name); -+ } else -+ trace("orphaned node %s deleted\n", node->name); -+ -+ /* Skip children in all cases in order to avoid more errors. */ -+ ret = WALK_TREE_SKIP_CHILDREN; -+ } -+ -+ return domain->nbentry > 0 ? ret : WALK_TREE_SUCCESS_STOP; -+} -+ -+static void domain_tree_remove(struct domain *domain) -+{ -+ int ret; -+ struct walk_funcs walkfuncs = { .enter = domain_tree_remove_sub }; -+ -+ if (domain->nbentry > 0) { -+ ret = walk_node_tree(domain, NULL, "/", &walkfuncs, domain); -+ if (ret == WALK_TREE_ERROR_STOP) -+ syslog(LOG_ERR, -+ "error when looking for orphaned nodes\n"); -+ } -+} -+ - static int destroy_domain(void *_domain) - { - struct domain *domain = _domain; - -+ domain_tree_remove(domain); -+ - list_del(&domain->list); - - if (!domain->introduced) -@@ -857,15 +911,15 @@ int domain_entry_inc(struct connection *conn, struct node *node) - struct domain *d; - unsigned int domid; - -- if (!conn) -+ if (!node->perms.p) - return 0; - -- domid = node->perms.p ? node->perms.p[0].id : conn->id; -+ domid = node->perms.p[0].id; - -- if (conn->transaction) { -+ if (conn && conn->transaction) { - transaction_entry_inc(conn->transaction, domid); - } else { -- d = (domid == conn->id && conn->domain) ? conn->domain -+ d = (conn && domid == conn->id && conn->domain) ? conn->domain - : find_or_alloc_existing_domain(domid); - if (d) - d->nbentry++; -@@ -926,23 +980,11 @@ int domain_alloc_permrefs(struct node_perms *perms) - * Remove permissions for no longer existing domains in order to avoid a new - * domain with the same domid inheriting the permissions. - */ --int domain_adjust_node_perms(struct connection *conn, struct node *node) -+int domain_adjust_node_perms(struct node *node) - { - unsigned int i; - int ret; - -- ret = chk_domain_generation(node->perms.p[0].id, node->generation); -- -- /* If the owner doesn't exist any longer give it to priv domain. */ -- if (!ret) { -- /* -- * In theory we'd need to update the number of dom0 nodes here, -- * but we could be called for a read of the node. So better -- * avoid the risk to overflow the node count of dom0. -- */ -- node->perms.p[0].id = priv_domid; -- } -- - for (i = 1; i < node->perms.num; i++) { - if (node->perms.p[i].perms & XS_PERM_IGNORE) - continue; -@@ -960,15 +1002,15 @@ void domain_entry_dec(struct connection *conn, struct node *node) - struct domain *d; - unsigned int domid; - -- if (!conn) -+ if (!node->perms.p) - return; - - domid = node->perms.p ? node->perms.p[0].id : conn->id; - -- if (conn->transaction) { -+ if (conn && conn->transaction) { - transaction_entry_dec(conn->transaction, domid); - } else { -- d = (domid == conn->id && conn->domain) ? conn->domain -+ d = (conn && domid == conn->id && conn->domain) ? conn->domain - : find_domain_struct(domid); - if (d) { - d->nbentry--; -@@ -1087,7 +1129,7 @@ int domain_memory_add(unsigned int domid, int mem, bool no_quota_check) - * exist, as accounting is done either for a domain related to - * the current connection, or for the domain owning a node - * (which is always existing, as the owner of the node is -- * tested to exist and replaced by domid 0 if not). -+ * tested to exist and deleted or replaced by domid 0 if not). - * So not finding the related domain MUST be an error in the - * data base. - */ -diff --git a/tools/xenstore/xenstored_domain.h b/tools/xenstore/xenstored_domain.h -index 0b4f56b8146c..491d7a325bd3 100644 ---- a/tools/xenstore/xenstored_domain.h -+++ b/tools/xenstore/xenstored_domain.h -@@ -65,7 +65,7 @@ bool domain_can_write(struct connection *conn); - bool domain_is_unprivileged(struct connection *conn); - - /* Remove node permissions for no longer existing domains. */ --int domain_adjust_node_perms(struct connection *conn, struct node *node); -+int domain_adjust_node_perms(struct node *node); - int domain_alloc_permrefs(struct node_perms *perms); - - /* Quota manipulation */ --- -2.37.4 - |