diff options
Diffstat (limited to 'core/nvram-format.c')
| -rw-r--r-- | core/nvram-format.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/core/nvram-format.c b/core/nvram-format.c index 227147e..b98aee1 100644 --- a/core/nvram-format.c +++ b/core/nvram-format.c @@ -208,12 +208,27 @@ static const char *find_next_key(const char *start, const char *end) */ const char *nvram_query(const char *key) { - const char *part_end = (const char *) skiboot_part_hdr + - skiboot_part_hdr->len * 16 - 1; - const char *start = (const char *) skiboot_part_hdr + - sizeof(*skiboot_part_hdr); + const char *part_end, *start; int key_len = strlen(key); + /* + * The running OS can modify the NVRAM as it pleases so we need to be + * a little paranoid and check that it's ok before we try parse it. + * + * NB: nvram_validate() can update skiboot_part_hdr + */ + if (!nvram_validate()) { + prerror("NVRAM: Look up for '%s' failed due to bad format!\n", + key); + return NULL; + } + + part_end = (const char *) skiboot_part_hdr + + skiboot_part_hdr->len * 16 - 1; + + start = (const char *) skiboot_part_hdr + + sizeof(*skiboot_part_hdr); + if (!key_len) { prlog(PR_WARNING, "NVRAM: search key is empty!\n"); return NULL; |