On Tue, Mar 19, 2024 at 03:53:24PM +0100, Neil Armstrong wrote:
> While meson_sm_read_efuse() doesn't overflow, the string is not
> zero terminated and env_set() will buffer overflow and add random
> characters to environment.
>
In the Linux kernel we would give this a CVE because it's information
disclosure bug...
> Signed-off-by: Neil Armstrong <neil.armstr...@linaro.org>
> ---
> board/amlogic/jethub-j80/jethub-j80.c | 6 ++++--
> board/amlogic/p200/p200.c | 3 ++-
> board/amlogic/p201/p201.c | 3 ++-
> board/amlogic/p212/p212.c | 3 ++-
> board/amlogic/q200/q200.c | 3 ++-
> 5 files changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/board/amlogic/jethub-j80/jethub-j80.c
> b/board/amlogic/jethub-j80/jethub-j80.c
> index 185880de13..d10492cc46 100644
> --- a/board/amlogic/jethub-j80/jethub-j80.c
> +++ b/board/amlogic/jethub-j80/jethub-j80.c
> @@ -28,8 +28,8 @@
> int misc_init_r(void)
> {
> u8 mac_addr[EFUSE_MAC_SIZE];
^^^^^^^^^^^^^^^^^^^^^^^^
This one is also a problem. You can't pass non-terminated strings to
eth_env_set_enetaddr(). We call strlen() on it in either hsearch_r() or
env_get_from_linear().
All the other functions had a mac_addr[] issue as well.
Btw, this kind of bug is a good candidate for a static checker warning.
I can create a Smatch check for this. It would probably be easier in
Coccinelle even, but I'm the Smatch maintainer.
regards,
dan carpenter
> - char serial[EFUSE_SN_SIZE];
> - char usid[EFUSE_USID_SIZE];
> + char serial[EFUSE_SN_SIZE + 1];
> + char usid[EFUSE_USID_SIZE + 1];
> ssize_t len;
> unsigned int adcval;
> int ret;
> @@ -46,6 +46,7 @@ int misc_init_r(void)
> if (!env_get("serial")) {
> len = meson_sm_read_efuse(EFUSE_SN_OFFSET, serial,
> EFUSE_SN_SIZE);
> + serial[len] = '\0';
> if (len == EFUSE_SN_SIZE)
> env_set("serial", serial);
