From 6bb1d52f0554f687ef27de46c0b9daac9d256d60 Mon Sep 17 00:00:00 2001

From: Lennart Poettering <lennart@poettering.net>

Date: Wed, 10 Oct 2018 11:34:30 +0200

Subject: [PATCH] tree-wide: various ubsan zero size memory fixes

Fixes: #10346

(cherry picked from commit 65f95765d05ddcd9e5849b68c379afa7e87d1248)

Resolves: #1683319

---

 src/basic/bitmap.c        | 2 +-

 src/basic/util.h          | 8 +++++++-

 src/test/test-hexdecoct.c | 2 +-

 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/basic/bitmap.c b/src/basic/bitmap.c

index c17c6a7a02..a4cd6451b0 100644

--- a/src/basic/bitmap.c

+++ b/src/basic/bitmap.c

@@ -206,7 +206,7 @@ bool bitmap_equal(Bitmap *a, Bitmap *b) {

                 return true;

         common_n_bitmaps = MIN(a->n_bitmaps, b->n_bitmaps);

-        if (memcmp(a->bitmaps, b->bitmaps, sizeof(uint64_t) * common_n_bitmaps) != 0)

+        if (memcmp_safe(a->bitmaps, b->bitmaps, sizeof(uint64_t) * common_n_bitmaps) != 0)

                 return false;

         c = a->n_bitmaps > b->n_bitmaps ? a : b;

diff --git a/src/basic/util.h b/src/basic/util.h

index b68ef25ed8..4659a21b06 100644

--- a/src/basic/util.h

+++ b/src/basic/util.h

@@ -134,7 +134,13 @@ static inline int memcmp_safe(const void *s1, const void *s2, size_t n) {

 int on_ac_power(void);

-#define memzero(x,l) (memset((x), 0, (l)))

+#define memzero(x,l)                                            \

+        ({                                                      \

+                size_t _l_ = (l);                               \

+                void *_x_ = (x);                                \

+                _l_ == 0 ? _x_ : memset(_x_, 0, _l_);           \

+        })

+

 #define zero(x) (memzero(&(x), sizeof(x)))

 static inline void *mempset(void *s, int c, size_t n) {

diff --git a/src/test/test-hexdecoct.c b/src/test/test-hexdecoct.c

index da9f3008bb..a972ddcef7 100644

--- a/src/test/test-hexdecoct.c

+++ b/src/test/test-hexdecoct.c

@@ -84,7 +84,7 @@ static void test_unhexmem_one(const char *s, size_t l, int retval) {

                         l = strlen(s);

                 assert_se(hex = hexmem(mem, len));

-                answer = strndupa(s, l);

+                answer = strndupa(s ?: "", l);

                 assert_se(streq(delete_chars(answer, WHITESPACE), hex));

         }

 }