efi_loader: efi_dp_find_obj() add protocol check

Let function efi_dp_find_obj() additionally check if a given protocol is
installed on the handle relating to the device-path.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

diff --git a/include/efi_loader.h b/include/efi_loader.h
index 6271d40..1ae47a8 100644 (file)
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -731,6 +731,7 @@ struct efi_device_path *efi_dp_next(const struct efi_device_path *dp);
 int efi_dp_match(const struct efi_device_path *a,
                 const struct efi_device_path *b);
 efi_handle_t efi_dp_find_obj(struct efi_device_path *dp,
+                            const efi_guid_t *guid,
                             struct efi_device_path **rem);
 /* get size of the first device path instance excluding end node */
 efi_uintn_t efi_dp_instance_size(const struct efi_device_path *dp);

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index d0f3e05..a7bc371 100644 (file)
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -1750,7 +1750,7 @@ efi_status_t efi_setup_loaded_image(struct efi_device_path *device_path,
        info->system_table = &systab;
 
        if (device_path) {
-               info->device_handle = efi_dp_find_obj(device_path, NULL);
+               info->device_handle = efi_dp_find_obj(device_path, NULL, NULL);
 
                dp = efi_dp_append(device_path, file_path);
                if (!dp) {

diff --git a/lib/efi_loader/efi_capsule.c b/lib/efi_loader/efi_capsule.c
index 613b531..011942b 100644 (file)
--- a/lib/efi_loader/efi_capsule.c
+++ b/lib/efi_loader/efi_capsule.c
@@ -680,7 +680,7 @@ static bool device_is_present_and_system_part(struct efi_device_path *dp)
 {
        efi_handle_t handle;
 
-       handle = efi_dp_find_obj(dp, NULL);
+       handle = efi_dp_find_obj(dp, NULL, NULL);
        if (!handle)
                return false;
 

diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c
index aeb5264..0a88029 100644 (file)
--- a/lib/efi_loader/efi_device_path.c
+++ b/lib/efi_loader/efi_device_path.c
@@ -160,17 +160,19 @@ struct efi_device_path *efi_dp_shorten(struct efi_device_path *dp)
 }
 
 /**
- * find_handle() - find handle by device path
+ * find_handle() - find handle by device path and installed protocol
  *
  * If @rem is provided, the handle with the longest partial match is returned.
  *
  * @dp:                device path to search
+ * @guid:      GUID of protocol that must be installed on path or NULL
  * @short_path:        use short form device path for matching
  * @rem:       pointer to receive remaining device path
  * Return:     matching handle
  */
-static efi_handle_t find_handle(struct efi_device_path *dp, bool short_path,
-                               struct efi_device_path **rem)
+static efi_handle_t find_handle(struct efi_device_path *dp,
+                               const efi_guid_t *guid, bool short_path,
+                               struct efi_device_path **rem)
 {
        efi_handle_t handle, best_handle = NULL;
        efi_uintn_t len, best_len = 0;
@@ -183,6 +185,11 @@ static efi_handle_t find_handle(struct efi_device_path *dp, bool short_path,
                efi_uintn_t len_current;
                efi_status_t ret;
 
+               if (guid) {
+                       ret = efi_search_protocol(handle, guid, &handler);
+                       if (ret != EFI_SUCCESS)
+                               continue;
+               }
                ret = efi_search_protocol(handle, &efi_guid_device_path,
                                          &handler);
                if (ret != EFI_SUCCESS)
@@ -195,13 +202,13 @@ static efi_handle_t find_handle(struct efi_device_path *dp, bool short_path,
                }
                len_current = efi_dp_instance_size(dp_current);
                if (rem) {
-                       if (len_current < len)
+                       if (len_current > len)
                                continue;
                } else {
                        if (len_current != len)
                                continue;
                }
-               if (memcmp(dp_current, dp, len))
+               if (memcmp(dp_current, dp, len_current))
                        continue;
                if (!rem)
                        return handle;
@@ -220,18 +227,20 @@ static efi_handle_t find_handle(struct efi_device_path *dp, bool short_path,
  * If @rem is provided, the handle with the longest partial match is returned.
  *
  * @dp:                device path to search
+ * @guid:      GUID of protocol that must be installed on path or NULL
  * @rem:       pointer to receive remaining device path
  * Return:     matching handle
  */
 efi_handle_t efi_dp_find_obj(struct efi_device_path *dp,
+                            const efi_guid_t *guid,
                             struct efi_device_path **rem)
 {
        efi_handle_t handle;
 
-       handle = find_handle(dp, false, rem);
+       handle = find_handle(dp, guid, false, rem);
        if (!handle)
                /* Match short form device path */
-               handle = find_handle(dp, true, rem);
+               handle = find_handle(dp, guid, true, rem);
 
        return handle;
 }

diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index 45127d1..d36a35d 100644 (file)
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -302,7 +302,7 @@ efi_fs_from_path(struct efi_device_path *full_path)
        efi_free_pool(file_path);
 
        /* Get the EFI object for the partition */
-       efiobj = efi_dp_find_obj(device_path, NULL);
+       efiobj = efi_dp_find_obj(device_path, NULL, NULL);
        efi_free_pool(device_path);
        if (!efiobj)
                return NULL;