vfs: select sanity NULL check

#9964
espressif · May 26, 2023 · da823ed · da823ed
1 parent fd5e03b
commit da823ed
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Showing 2 changed files with 18 additions and 4 deletions.
diff --git a/components/vfs/vfs.c b/components/vfs/vfs.c
@@ -985,7 +985,9 @@ int esp_vfs_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *errorfds
         const vfs_entry_t *vfs = get_vfs_for_index(i);
         fds_triple_t *item = &vfs_fds_triple[i];
 
-        if (vfs && vfs->vfs.start_select && item->isset) {
+        if (vfs && !vfs->vfs.start_select) {
+            ESP_LOGD(TAG, "start_select function callback for this vfs (s_vfs[%d]) is not defined", vfs->offset);
+        } else if (vfs && vfs->vfs.start_select && item->isset) {
             // call start_select for all non-socket VFSs with has at least one FD set in readfds, writefds, or errorfds
             // note: it can point to socket VFS but item->isset will be false for that
             ESP_LOGD(TAG, "calling start_select for VFS ID %d with the following local FDs", i);
@@ -996,7 +998,9 @@ int esp_vfs_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *errorfds
                     driver_args + i);
 
             if (err != ESP_OK) {
-                call_end_selects(i, vfs_fds_triple, driver_args);
+                if (err != ESP_ERR_NOT_SUPPORTED) {
+                    call_end_selects(i, vfs_fds_triple, driver_args);
+                }
                 (void) set_global_fd_sets(vfs_fds_triple, vfs_count, readfds, writefds, errorfds);
                 if (sel_sem.is_sem_local && sel_sem.sem) {
                     vSemaphoreDelete(sel_sem.sem);

diff --git a/components/vfs/vfs_console.c b/components/vfs/vfs_console.c
@@ -119,12 +119,22 @@ int console_access(const char *path, int amode)
 static esp_err_t console_start_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
         esp_vfs_select_sem_t select_sem, void **end_select_args)
 {
-    return get_vfs_for_index(primary_vfs_index)->vfs.start_select(nfds, readfds, writefds, exceptfds, select_sem, end_select_args);
+    const vfs_entry_t* vfs_entry = get_vfs_for_index(primary_vfs_index);
+    // start_select is not guaranteed be implemented even though CONFIG_VFS_SUPPORT_SELECT is enabled in sdkconfig
+    if (vfs_entry && vfs_entry->vfs.start_select) {
+        return vfs_entry->vfs.start_select(nfds, readfds, writefds, exceptfds, select_sem, end_select_args);
+    }
+    return ESP_ERR_NOT_SUPPORTED;
 }
 
 esp_err_t console_end_select(void *end_select_args)
 {
-    return get_vfs_for_index(primary_vfs_index)->vfs.end_select(end_select_args);
+    const vfs_entry_t* vfs_entry = get_vfs_for_index(primary_vfs_index);
+    // end_select is not guaranteed be implemented even though CONFIG_VFS_SUPPORT_SELECT is enabled in sdkconfig
+    if (vfs_entry && vfs_entry->vfs.end_select) {
+        return vfs_entry->vfs.end_select(end_select_args);
+    }
+    return ESP_ERR_NOT_SUPPORTED;
 }
 
 #endif // CONFIG_VFS_SUPPORT_SELECT