env: mtd: initialize saved_buf pointer

When sect_size is greater than the CONFIG_ENV_SIZE, this wild
pointer will cause CPU halt or system crash.

Fixes: 03fb08d4aef8 ("env: Introduce support for MTD")
Signed-off-by: Shiji Yang <yangshiji66@outlook.com>

diff --git a/env/mtd.c b/env/mtd.c
index ad263ed4b29b636a97e2d6c1ecdcfc4d54264652..b26ee80985a025dde24b614782de6f7744474ffb 100644 (file)
--- a/env/mtd.c
+++ b/env/mtd.c
@@ -201,7 +201,7 @@ static int env_mtd_erase(void)
 {
        struct mtd_info *mtd_env;
        u32 sect_size, sect_num;
-       char *saved_buf, *tmp;
+       char *saved_buf = NULL, *tmp;
        struct erase_info ei;
        size_t ret_len;
        int remaining;