!1178 fix: /dev/mem 及 /proc/fs_cache 权限漏洞修复

Merge pull request !1178 from yinjiaming/fix

drivers/char/mem/src/mem.c

@@ -97,5 +97,5 @@ static const struct file_operations_vfs g_memDevOps = {
 
 int DevMemRegister(void)
 {
-    return register_driver("/dev/mem", &g_memDevOps, 0666, 0); /* 0666: file mode */
+    return register_driver("/dev/mem", &g_memDevOps, 0644, 0); /* 0644: file mode */
 }

fs/jffs2/src/vfs_jffs2.c

@@ -490,14 +490,14 @@ off_t VfsJffs2Seek(struct file *filep, off_t offset, int whence)
     filePos = filep->f_pos;
 
     switch (whence) {
-        case SEEK_SET:
-            filePos = offset;
-            break;
-
         case SEEK_CUR:
             filePos += offset;
             break;
 
+        case SEEK_SET:
+            filePos = offset;
+            break;
+
         case SEEK_END:
             filePos = node->i_size + offset;
             break;

fs/proc/os_adapt/fs_cache_proc.c

@@ -207,7 +207,7 @@ static const struct ProcFileOperations FS_CACHE_PROC_FOPS = {
 
 void ProcFsCacheInit(void)
 {
-    struct ProcDirEntry *pde = CreateProcEntry("fs_cache", 0, NULL);
+    struct ProcDirEntry *pde = CreateProcEntry("fs_cache", 0400, NULL);
     if (pde == NULL) {
         PRINT_ERR("create fs_cache error!\n");
         return;

kernel/extended/plimit/los_devicelimit.c

@@ -485,29 +485,35 @@ UINT32 OsDevLimitWriteDeny(ProcLimitSet *plimit, const CHAR *buf, UINT32 size)
     return DevLimitUpdateAccess(plimit, buf, DEVLIMIT_DENY);
 }
 
-STATIC VOID DevLimitItemSetAccess(CHAR *acc, INT16 access)
+STATIC VOID DevLimitItemSetAccess(CHAR *accArray, INT16 access)
 {
     INT32 index = 0;
     (VOID)memset_s(acc, ACCLEN, 0, ACCLEN);
     if (access & DEVLIMIT_ACC_READ) {
-        acc[index++] = 'r';
+        accArray[index] = 'r';
+        index++;
     }
     if (access & DEVLIMIT_ACC_WRITE) {
-        acc[index++] = 'w';
+        accArray[index] = 'w';
+        index++;
     }
     if (access & DEVLIMIT_ACC_MKNOD) {
-        acc[index++] = 'm';
+        accArray[index] = 'm';
+        index++;
     }
 }
 
 STATIC CHAR DevLimitItemTypeToChar(INT16 type)
 {
-    if (type == DEVLIMIT_DEV_ALL) {
-        return 'a';
-    } else if (type == DEVLIMIT_DEV_CHAR) {
-        return 'c';
-    } else if (type == DEVLIMIT_DEV_BLOCK) {
-        return 'b';
+    switch (type) {
+        case DEVLIMIT_DEV_ALL:
+            return 'a';
+        case DEVLIMIT_DEV_CHAR:
+            return 'c';
+        case DEVLIMIT_DEV_BLOCK:
+            return 'b';
+        default:
+            break;
     }
     return 'X';
 }