diff options
Diffstat (limited to 'src/common/crypto.c')
| -rw-r--r-- | src/common/crypto.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/common/crypto.c b/src/common/crypto.c index 9cc5ee01fa..de4f9db94f 100644 --- a/src/common/crypto.c +++ b/src/common/crypto.c @@ -2939,6 +2939,7 @@ smartlist_shuffle(smartlist_t *sl) /** * 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 @@ -2956,6 +2957,13 @@ smartlist_shuffle(smartlist_t *sl) void memwipe(void *mem, uint8_t byte, size_t sz) { + if (mem == NULL || sz == 0) { + return; + } + + /* 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. */ |