dev-lang/python: fix unaligned memory access

Thanks to Rolf Eike Beer for the patches. Closes: https://bugs.gentoo.org/636400 Package-Manager: Portage-2.3.24, Repoman-2.3.6_p81
johu · Apr 19, 2018 · 0d123a4 · 0d123a4
1 parent 9bd7b7a
commit 0d123a4
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diff --git a/dev-lang/python/files/python-3.5.5-hash-unaligned.patch b/dev-lang/python/files/python-3.5.5-hash-unaligned.patch
@@ -0,0 +1,43 @@
+The hash implementation casts the input pointer to uint64_t* and directly reads
+from this, which may cause unaligned accesses. Use memcpy() instead so this code
+will not crash with SIGBUS on sparc.
+
+--- a/Python/pyhash.c	2017-11-29 10:21:20.283094068 +0100
++++ b/Python/pyhash.c	2017-11-29 10:24:26.733087813 +0100
+@@ -372,7 +372,7 @@ siphash24(const void *src, Py_ssize_t sr
+     PY_UINT64_T k0 = _le64toh(_Py_HashSecret.siphash.k0);
+     PY_UINT64_T k1 = _le64toh(_Py_HashSecret.siphash.k1);
+     PY_UINT64_T b = (PY_UINT64_T)src_sz << 56;
+-    const PY_UINT64_T *in = (PY_UINT64_T*)src;
++    const PY_UINT8_T *in = (PY_UINT8_T*)src;
+
+     PY_UINT64_T v0 = k0 ^ 0x736f6d6570736575ULL;
+     PY_UINT64_T v1 = k1 ^ 0x646f72616e646f6dULL;
+@@ -381,12 +381,14 @@ siphash24(const void *src, Py_ssize_t sr
+
+     PY_UINT64_T t;
+     PY_UINT8_T *pt;
+-    PY_UINT8_T *m;
++    const PY_UINT8_T *m;
+
+     while (src_sz >= 8) {
+-        PY_UINT64_T mi = _le64toh(*in);
+-        in += 1;
+-        src_sz -= 8;
++        PY_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;
+@@ -394,7 +396,7 @@ siphash24(const void *src, Py_ssize_t sr
+
+     t = 0;
+     pt = (PY_UINT8_T *)&t;
+-    m = (PY_UINT8_T *)in;
++    m = in;
+     switch (src_sz) {
+         case 7: pt[6] = m[6];
+         case 6: pt[5] = m[5];
diff --git a/dev-lang/python/files/python-3.6.5-hash-unaligned.patch b/dev-lang/python/files/python-3.6.5-hash-unaligned.patch
@@ -0,0 +1,42 @@
+The hash implementation casts the input pointer to uint64_t* and directly reads
+from this, which may cause unaligned accesses. Use memcpy() instead so this code
+will not crash with SIGBUS on sparc.
+
+--- a/Python/pyhash.c	2017-11-29 10:21:20.283094068 +0100
++++ b/Python/pyhash.c	2017-11-29 10:24:26.733087813 +0100
+@@ -369,7 +369,7 @@
+     uint64_t k0 = _le64toh(_Py_HashSecret.siphash.k0);
+     uint64_t k1 = _le64toh(_Py_HashSecret.siphash.k1);
+     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;
+@@ -378,11 +378,13 @@
+
+     uint64_t t;
+     uint8_t *pt;
+-    uint8_t *m;
++    const 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);
+@@ -391,7 +393,7 @@
+
+     t = 0;
+     pt = (uint8_t *)&t;
+-    m = (uint8_t *)in;
++    m = in;
+     switch (src_sz) {
+         case 7: pt[6] = m[6]; /* fall through */
+         case 6: pt[5] = m[5]; /* fall through */
diff --git a/dev-lang/python/python-3.4.8.ebuild b/dev-lang/python/python-3.4.8.ebuild
@@ -74,6 +74,7 @@ src_prepare() {
 	epatch "${FILESDIR}/${PN}-3.4.5-cross.patch"
 	epatch "${FILESDIR}/3.4-getentropy-linux.patch"
 	epatch "${FILESDIR}/3.6-disable-nis.patch"
+	epatch "${FILESDIR}/python-3.5.5-hash-unaligned.patch"
 
 	epatch_user
 

diff --git a/dev-lang/python/python-3.5.5.ebuild b/dev-lang/python/python-3.5.5.ebuild
@@ -75,6 +75,7 @@ src_prepare() {
 	epatch "${FILESDIR}/${PN}-3.5-distutils-OO-build.patch"
 	epatch "${FILESDIR}/3.6-disable-nis.patch"
 	epatch "${FILESDIR}/python-3.5.5-libressl-compatibility.patch"
+	epatch "${FILESDIR}/python-3.5.5-hash-unaligned.patch"
 
 	epatch_user
 

diff --git a/dev-lang/python/python-3.6.5.ebuild b/dev-lang/python/python-3.6.5.ebuild
@@ -69,6 +69,7 @@ src_prepare() {
 		"${FILESDIR}/${PN}-3.5-distutils-OO-build.patch"
 		"${FILESDIR}/3.6.5-disable-nis.patch"
 		"${FILESDIR}/python-3.6.5-libressl-compatibility.patch"
+		"${FILESDIR}/python-3.6.5-hash-unaligned.patch"
 	)
 
 	default