diff options
Diffstat (limited to 'src/common/crypto.c')
| -rw-r--r-- | src/common/crypto.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/src/common/crypto.c b/src/common/crypto.c index f4e86683d9..43bf5bd6b6 100644 --- a/src/common/crypto.c +++ b/src/common/crypto.c @@ -3056,6 +3056,7 @@ secret_to_key(char *key_out, size_t key_out_len, const char *secret, /** * Destroy the <b>sz</b> bytes of data stored at <b>mem</b>, setting them to * the value <b>byte</b>. + * If <b>mem</b> is NULL or <b>sz</b> is zero, nothing happens. * * This function is preferable to memset, since many compilers will happily * optimize out memset() when they can convince themselves that the data being @@ -3073,6 +3074,15 @@ secret_to_key(char *key_out, size_t key_out_len, const char *secret, void memwipe(void *mem, uint8_t byte, size_t sz) { + if (sz == 0) { + return; + } + /* If sz is nonzero, then mem must not be NULL. */ + tor_assert(mem != NULL); + + /* Data this large is likely to be an underflow. */ + tor_assert(sz < SIZE_T_CEILING); + /* Because whole-program-optimization exists, we may not be able to just * have this function call "memset". A smart compiler could inline it, then * eliminate dead memsets, and declare itself to be clever. */ |