diff options
| -rw-r--r-- | Misc/NEWS.d/next/Core and Builtins/2018-04-25-20-44-42.bpo-28055.f49kfC.rst | 1 | ||||
| -rw-r--r-- | Python/pyhash.c | 26 |
2 files changed, 14 insertions, 13 deletions
diff --git a/Misc/NEWS.d/next/Core and Builtins/2018-04-25-20-44-42.bpo-28055.f49kfC.rst b/Misc/NEWS.d/next/Core and Builtins/2018-04-25-20-44-42.bpo-28055.f49kfC.rst new file mode 100644 index 0000000..c7d8499 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2018-04-25-20-44-42.bpo-28055.f49kfC.rst @@ -0,0 +1 @@ +Fix unaligned accesses in siphash24(). Patch by Rolf Eike Beer. diff --git a/Python/pyhash.c b/Python/pyhash.c index 9e6e594..6fc12fd 100644 --- a/Python/pyhash.c +++ b/Python/pyhash.c @@ -366,7 +366,7 @@ static PyHash_FuncDef PyHash_Func = {fnv, "fnv", 8 * SIZEOF_PY_HASH_T, static uint64_t siphash24(uint64_t k0, uint64_t k1, const void *src, Py_ssize_t src_sz) { uint64_t b = (uint64_t)src_sz << 56; - const uint64_t *in = (uint64_t*)src; + const uint8_t *in = (uint8_t*)src; uint64_t v0 = k0 ^ 0x736f6d6570736575ULL; uint64_t v1 = k1 ^ 0x646f72616e646f6dULL; @@ -375,12 +375,13 @@ siphash24(uint64_t k0, uint64_t k1, const void *src, Py_ssize_t src_sz) { uint64_t t; uint8_t *pt; - uint8_t *m; while (src_sz >= 8) { - uint64_t mi = _le64toh(*in); - in += 1; - src_sz -= 8; + uint64_t mi; + memcpy(&mi, in, sizeof(mi)); + mi = _le64toh(mi); + in += sizeof(mi); + src_sz -= sizeof(mi); v3 ^= mi; DOUBLE_ROUND(v0,v1,v2,v3); v0 ^= mi; @@ -388,15 +389,14 @@ siphash24(uint64_t k0, uint64_t k1, const void *src, Py_ssize_t src_sz) { t = 0; pt = (uint8_t *)&t; - m = (uint8_t *)in; switch (src_sz) { - case 7: pt[6] = m[6]; /* fall through */ - case 6: pt[5] = m[5]; /* fall through */ - case 5: pt[4] = m[4]; /* fall through */ - case 4: memcpy(pt, m, sizeof(uint32_t)); break; - case 3: pt[2] = m[2]; /* fall through */ - case 2: pt[1] = m[1]; /* fall through */ - case 1: pt[0] = m[0]; /* fall through */ + case 7: pt[6] = in[6]; /* fall through */ + case 6: pt[5] = in[5]; /* fall through */ + case 5: pt[4] = in[4]; /* fall through */ + case 4: memcpy(pt, in, sizeof(uint32_t)); break; + case 3: pt[2] = in[2]; /* fall through */ + case 2: pt[1] = in[1]; /* fall through */ + case 1: pt[0] = in[0]; /* fall through */ } b |= _le64toh(t); |