diff options
| -rw-r--r-- | drivers/of/overlay.c | 58 |
1 files changed, 49 insertions, 9 deletions
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index c8f88b0836a3..8af8115bd36e 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -392,14 +392,6 @@ static int add_changeset_property(struct overlay_changeset *ovcs, * a live devicetree created from Open Firmware. * * NOTE_2: Multiple mods of created nodes not supported. - * If more than one fragment contains a node that does not already exist - * in the live tree, then for each fragment of_changeset_attach_node() - * will add a changeset entry to add the node. When the changeset is - * applied, __of_attach_node() will attach the node twice (once for - * each fragment). At this point the device tree will be corrupted. - * - * TODO: add integrity check to ensure that multiple fragments do not - * create the same node. * * Returns 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if * invalid @overlay. @@ -517,6 +509,54 @@ static int build_changeset_symbols_node(struct overlay_changeset *ovcs, } /** + * check_changeset_dup_add_node() - changeset validation: duplicate add node + * @ovcs: Overlay changeset + * + * Check changeset @ovcs->cset for multiple add node entries for the same + * node. + * + * Returns 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if + * invalid overlay in @ovcs->fragments[]. + */ +static int check_changeset_dup_add_node(struct overlay_changeset *ovcs) +{ + struct of_changeset_entry *ce_1, *ce_2; + char *fn_1, *fn_2; + int name_match; + + list_for_each_entry(ce_1, &ovcs->cset.entries, node) { + + if (ce_1->action == OF_RECONFIG_ATTACH_NODE || + ce_1->action == OF_RECONFIG_DETACH_NODE) { + + ce_2 = ce_1; + list_for_each_entry_continue(ce_2, &ovcs->cset.entries, node) { + if (ce_2->action == OF_RECONFIG_ATTACH_NODE || + ce_2->action == OF_RECONFIG_DETACH_NODE) { + /* inexpensive name compare */ + if (!of_node_cmp(ce_1->np->full_name, + ce_2->np->full_name)) { + /* expensive full path name compare */ + fn_1 = kasprintf(GFP_KERNEL, "%pOF", ce_1->np); + fn_2 = kasprintf(GFP_KERNEL, "%pOF", ce_2->np); + name_match = !strcmp(fn_1, fn_2); + kfree(fn_1); + kfree(fn_2); + if (name_match) { + pr_err("ERROR: multiple overlay fragments add and/or delete node %pOF\n", + ce_1->np); + return -EINVAL; + } + } + } + } + } + } + + return 0; +} + +/** * build_changeset() - populate overlay changeset in @ovcs from @ovcs->fragments * @ovcs: Overlay changeset * @@ -571,7 +611,7 @@ static int build_changeset(struct overlay_changeset *ovcs) } } - return 0; + return check_changeset_dup_add_node(ovcs); } /* |