diff options
| author | Marek Vasut <[email protected]> | 2020-07-07 20:51:38 +0200 |
|---|---|---|
| committer | Tom Rini <[email protected]> | 2020-07-31 10:13:00 -0400 |
| commit | 47f3b1f243acfe755340753c5d467ba781618fa6 (patch) | |
| tree | 472b24b571e8a94bcafddb581f8b5f6e8bad1269 | |
| parent | 890feecaab72a630eac3344443e053173f4ad02f (diff) | |
env: Add option to only ever append environment
Add configuration option which prevents the environment hash table to be
ever cleared and reloaded with different content. This is useful in case
the first environment loaded into the hash table contains e.g. sensitive
content which must not be dropped or reloaded.
Signed-off-by: Marek Vasut <[email protected]>
Reviewed-by: Tom Rini <[email protected]>
| -rw-r--r-- | env/Kconfig | 9 | ||||
| -rw-r--r-- | env/env.c | 2 | ||||
| -rw-r--r-- | lib/hashtable.c | 4 |
3 files changed, 15 insertions, 0 deletions
diff --git a/env/Kconfig b/env/Kconfig index dcc525d4ede..1cae1edf6a9 100644 --- a/env/Kconfig +++ b/env/Kconfig @@ -614,6 +614,15 @@ config DELAY_ENVIRONMENT later by U-Boot code. With CONFIG_OF_CONTROL this is instead controlled by the value of /config/load-environment. +config ENV_APPEND + bool "Always append the environment with new data" + default n + help + If defined, the environment hash table is only ever appended with new + data, but the existing hash table can never be dropped and reloaded + with newly imported data. This may be used in combination with static + flags to e.g. to protect variables which must not be modified. + config ENV_ACCESS_IGNORE_FORCE bool "Block forced environment operations" default n diff --git a/env/env.c b/env/env.c index 2af2fae23cd..42c7d8155e1 100644 --- a/env/env.c +++ b/env/env.c @@ -201,7 +201,9 @@ int env_load(void) printf("OK\n"); gd->env_load_prio = prio; +#if !CONFIG_IS_ENABLED(ENV_APPEND) return 0; +#endif } else if (ret == -ENOMSG) { /* Handle "bad CRC" case */ if (best_prio == -1) diff --git a/lib/hashtable.c b/lib/hashtable.c index 7b6781bc354..ef834badc52 100644 --- a/lib/hashtable.c +++ b/lib/hashtable.c @@ -826,6 +826,10 @@ int himport_r(struct hsearch_data *htab, if (nvars) memcpy(localvars, vars, sizeof(vars[0]) * nvars); +#if CONFIG_IS_ENABLED(ENV_APPEND) + flag |= H_NOCLEAR; +#endif + if ((flag & H_NOCLEAR) == 0 && !nvars) { /* Destroy old hash table if one exists */ debug("Destroy Hash Table: %p table = %p\n", htab, |