Dump (leak) info using utrace(2) and compile the code always in

except for bootblocks. This way we have built-in leak detecction
always (if enable by malloc flags). See man pages for details.

2 files changed, 199 insertions, 148 deletions

diff --git a/src/lib/libc/stdlib/malloc.3 b/src/lib/libc/stdlib/malloc.3
index b35b9220f6..e69e7c065f 100644
--- a/src/lib/libc/stdlib/malloc.3
+++ b/src/lib/libc/stdlib/malloc.3
@@ -30,9 +30,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: malloc.3,v 1.130 2023/04/01 18:47:51 otto Exp $
+.\"     $OpenBSD: malloc.3,v 1.131 2023/04/16 19:46:17 otto Exp $
 .\"
-.Dd $Mdocdate: April 1 2023 $
+.Dd $Mdocdate: April 16 2023 $
 .Dt MALLOC 3
 .Os
 .Sh NAME
@@ -284,12 +284,17 @@ If it has been corrupted, the process is aborted.
 .It Cm D
 .Dq Dump .
 .Fn malloc
-will dump statistics to the file
-.Pa ./malloc.out ,
-if it already exists,
+will dump a leak report using
+.Xr utrace 2
 at exit.
-This option requires the library to have been compiled with -DMALLOC_STATS in
-order to have any effect.
+To record the dump:
+.Pp
+.Dl $ MALLOC_OPTIONS=D ktrace -tu program ...
+.Pp
+To view the leak report:
+.Pp
+.Dl $ kdump -u malloc ...
+.Pp
 .It Cm F
 .Dq Freecheck .
 Enable more extensive double free and use after free detection.
@@ -340,6 +345,11 @@ Enable all options suitable for security auditing.
 Enable use after free protection for larger allocations.
 Unused pages on the freelist are read and write protected to
 cause a segmentation fault upon access.
+.It Cm V
+.Dq Verbose .
+Use with
+.Cm D
+to get a verbose dump of malloc's internal state.
 .It Cm X
 .Dq xmalloc .
 Rather than return failure,
diff --git a/src/lib/libc/stdlib/malloc.c b/src/lib/libc/stdlib/malloc.c
index 0df1fe3e4a..a661b9d252 100644
--- a/src/lib/libc/stdlib/malloc.c
+++ b/src/lib/libc/stdlib/malloc.c
@@ -1,6 +1,6 @@
-/*      $OpenBSD: malloc.c,v 1.280 2023/04/05 06:25:38 otto Exp $       */
+/*      $OpenBSD: malloc.c,v 1.281 2023/04/16 19:46:17 otto Exp $       */
 /*
- * Copyright (c) 2008, 2010, 2011, 2016 Otto Moerbeek <otto@drijf.net>
+ * Copyright (c) 2008, 2010, 2011, 2016, 2023 Otto Moerbeek <otto@drijf.net>
  * Copyright (c) 2012 Matthew Dempsky <matthew@openbsd.org>
  * Copyright (c) 2008 Damien Miller <djm@openbsd.org>
  * Copyright (c) 2000 Poul-Henning Kamp <phk@FreeBSD.org>
@@ -23,7 +23,9 @@
  * can buy me a beer in return. Poul-Henning Kamp
  */
 
-/* #define MALLOC_STATS */
+#ifndef MALLOC_SMALL
+#define MALLOC_STATS
+#endif
 
 #include <sys/types.h>
 #include <sys/queue.h>
@@ -39,8 +41,10 @@
 #include <unistd.h>
 
 #ifdef MALLOC_STATS
+#include <sys/types.h>
 #include <sys/tree.h>
-#include <fcntl.h>
+#include <sys/ktrace.h>
+#include <dlfcn.h>
 #endif
 
 #include "thread_private.h"
@@ -224,11 +228,16 @@ struct malloc_readonly {
         u_int   junk_loc;               /* variation in location of junk */
         size_t  malloc_guard;           /* use guard pages after allocations? */
 #ifdef MALLOC_STATS
-        int     malloc_stats;           /* dump statistics at end */
+        int     malloc_stats;           /* dump leak report at end */
+        int     malloc_verbose;         /* dump verbose statistics at end */
+#define DO_STATS        mopts.malloc_stats
+#else
+#define DO_STATS        0
 #endif
         u_int32_t malloc_canary;        /* Matched against ones in pool */
 };
 
+
 /* This object is mapped PROT_READ after initialisation to prevent tampering */
 static union {
         struct malloc_readonly mopts;
@@ -243,15 +252,11 @@ static __dead void wrterror(struct dir_info *d, char *msg, ...)
     __attribute__((__format__ (printf, 2, 3)));
 
 #ifdef MALLOC_STATS
-void malloc_dump(int, int, struct dir_info *);
+void malloc_dump(void);
 PROTO_NORMAL(malloc_dump);
-void malloc_gdump(int);
-PROTO_NORMAL(malloc_gdump);
 static void malloc_exit(void);
-#define CALLER  __builtin_return_address(0)
-#else
-#define CALLER  NULL
 #endif
+#define CALLER  (DO_STATS ? __builtin_return_address(0) : NULL)
 
 /* low bits of r->p determine size: 0 means >= page size and r->size holding
  * real size, otherwise low bits is the bucket + 1
@@ -318,9 +323,9 @@ wrterror(struct dir_info *d, char *msg, ...)
         dprintf(STDERR_FILENO, "\n");
 
 #ifdef MALLOC_STATS
-        if (mopts.malloc_stats)
-                malloc_gdump(STDERR_FILENO);
-#endif /* MALLOC_STATS */
+        if (DO_STATS && mopts.malloc_verbose)
+                malloc_dump();
+#endif
 
         errno = saved_errno;
 
@@ -416,6 +421,14 @@ omalloc_parseopt(char opt)
         case 'U':
                 mopts.malloc_freeunmap = 1;
                 break;
+#ifdef MALLOC_STATS
+        case 'v':
+                mopts.malloc_verbose = 0;
+                break;
+        case 'V':
+                mopts.malloc_verbose = 1;
+                break;
+#endif /* MALLOC_STATS */
         case 'x':
                 mopts.malloc_xmalloc = 0;
                 break;
@@ -486,11 +499,11 @@ omalloc_init(void)
         }
 
 #ifdef MALLOC_STATS
-        if (mopts.malloc_stats && (atexit(malloc_exit) == -1)) {
+        if (DO_STATS && (atexit(malloc_exit) == -1)) {
                 dprintf(STDERR_FILENO, "malloc() warning: atexit(2) failed."
                     " Will not be able to dump stats on exit\n");
         }
-#endif /* MALLOC_STATS */
+#endif
 
         while ((mopts.malloc_canary = arc4random()) == 0)
                 ;
@@ -596,9 +609,7 @@ insert(struct dir_info *d, void *p, size_t sz, void *f)
         }
         d->r[index].p = p;
         d->r[index].size = sz;
-#ifdef MALLOC_STATS
-        d->r[index].f = f;
-#endif
+        STATS_SETF(&d->r[index], f);
         d->regions_free--;
         return 0;
 }
@@ -1104,12 +1115,10 @@ malloc_bytes(struct dir_info *d, size_t size, void *f)
                 }
         }
 found:
-#ifdef MALLOC_STATS
-        if (i == 0 && k == 0) {
+        if (i == 0 && k == 0 && DO_STATS) {
                 struct region_info *r = find(d, bp->page);
-                r->f = f;
+                STATS_SETF(r, f);
         }
-#endif
 
         *lp ^= 1 << k;
 
@@ -1193,6 +1202,9 @@ free_bytes(struct dir_info *d, struct region_info *r, void *ptr)
         info = (struct chunk_info *)r->size;
         chunknum = find_chunknum(d, info, ptr, 0);
 
+        if (chunknum == 0)
+                STATS_SETF(r, NULL);
+
         info->bits[chunknum / MALLOC_BITS] |= 1U << (chunknum % MALLOC_BITS);
         info->free++;
 
@@ -1214,7 +1226,7 @@ free_bytes(struct dir_info *d, struct region_info *r, void *ptr)
         unmap(d, info->page, MALLOC_PAGESIZE, 0);
 
         delete(d, r);
-                mp = &d->chunk_info_list[info->bucket];
+        mp = &d->chunk_info_list[info->bucket];
         LIST_INSERT_HEAD(mp, info, entries);
 }
 
@@ -1694,9 +1706,11 @@ orealloc(struct dir_info **argpool, void *p, size_t newsz, void *f)
         r = findpool(p, *argpool, &pool, &saved_function);
 
         REALSIZE(oldsz, r);
-        if (mopts.chunk_canaries && oldsz <= MALLOC_MAXCHUNK) {
-                info = (struct chunk_info *)r->size;
-                chunknum = find_chunknum(pool, info, p, 0);
+        if (oldsz <= MALLOC_MAXCHUNK) {
+                if (DO_STATS || mopts.chunk_canaries) {
+                        info = (struct chunk_info *)r->size;
+                        chunknum = find_chunknum(pool, info, p, 0);
+                }
         }
 
         goldsz = oldsz;
@@ -1808,7 +1822,8 @@ orealloc(struct dir_info **argpool, void *p, size_t newsz, void *f)
                         info->bits[info->offset + chunknum] = newsz;
                         fill_canary(p, newsz, B2SIZE(info->bucket));
                 }
-                STATS_SETF(r, f);
+                if (DO_STATS && chunknum == 0)
+                        STATS_SETF(r, f);
                 ret = p;
         } else if (newsz != oldsz || forced) {
                 /* create new allocation */
@@ -1825,7 +1840,8 @@ orealloc(struct dir_info **argpool, void *p, size_t newsz, void *f)
                 /* oldsz == newsz */
                 if (newsz != 0)
                         wrterror(pool, "realloc internal inconsistency");
-                STATS_SETF(r, f);
+                if (DO_STATS && chunknum == 0)
+                        STATS_SETF(r, f);
                 ret = p;
         }
 done:
@@ -2225,6 +2241,35 @@ aligned_alloc(size_t alignment, size_t size)
 
 #ifdef MALLOC_STATS
 
+static void
+ulog(const char *format, ...)
+{
+        va_list ap;
+        static char* buf;
+        static size_t filled;
+        int len;
+
+        if (buf == NULL)
+                buf = MMAP(KTR_USER_MAXLEN, 0);
+        if (buf == MAP_FAILED)
+                return;
+
+        va_start(ap, format);
+        len = vsnprintf(buf + filled, KTR_USER_MAXLEN - filled, format, ap);
+        va_end(ap);
+        if (len < 0)
+                return;
+        if (len > KTR_USER_MAXLEN - filled)
+                len = KTR_USER_MAXLEN - filled;
+        filled += len;
+        if (filled > 0) {
+                if (filled == KTR_USER_MAXLEN || buf[filled - 1] == '\n') {
+                        utrace("malloc", buf, filled);
+                        filled = 0;
+                }
+        }
+}
+
 struct malloc_leak {
         void *f;
         size_t total_size;
@@ -2242,12 +2287,12 @@ leakcmp(const struct leaknode *e1, const struct leaknode *e2)
         return e1->d.f < e2->d.f ? -1 : e1->d.f > e2->d.f;
 }
 
-static RBT_HEAD(leaktree, leaknode) leakhead;
+RBT_HEAD(leaktree, leaknode);
 RBT_PROTOTYPE(leaktree, leaknode, entry, leakcmp);
 RBT_GENERATE(leaktree, leaknode, entry, leakcmp);
 
 static void
-putleakinfo(void *f, size_t sz, int cnt)
+putleakinfo(struct leaktree *leaks, void *f, size_t sz, int cnt)
 {
         struct leaknode key, *p;
         static struct leaknode *page;
@@ -2257,7 +2302,7 @@ putleakinfo(void *f, size_t sz, int cnt)
                 return;
 
         key.d.f = f;
-        p = RBT_FIND(leaktree, &leakhead, &key);
+        p = RBT_FIND(leaktree, leaks, &key);
         if (p == NULL) {
                 if (page == NULL ||
                     used >= MALLOC_PAGESIZE / sizeof(struct leaknode)) {
@@ -2270,72 +2315,75 @@ putleakinfo(void *f, size_t sz, int cnt)
                 p->d.f = f;
                 p->d.total_size = sz * cnt;
                 p->d.count = cnt;
-                RBT_INSERT(leaktree, &leakhead, p);
+                RBT_INSERT(leaktree, leaks, p);
         } else {
                 p->d.total_size += sz * cnt;
                 p->d.count += cnt;
         }
 }
 
-static struct malloc_leak *malloc_leaks;
-
 static void
-dump_leaks(int fd)
+dump_leaks(struct leaktree *leaks)
 {
         struct leaknode *p;
-        unsigned int i = 0;
-
-        dprintf(fd, "Leak report\n");
-        dprintf(fd, "                 f     sum      #    avg\n");
-        /* XXX only one page of summary */
-        if (malloc_leaks == NULL)
-                malloc_leaks = MMAP(MALLOC_PAGESIZE, 0);
-        if (malloc_leaks != MAP_FAILED)
-                memset(malloc_leaks, 0, MALLOC_PAGESIZE);
-        RBT_FOREACH(p, leaktree, &leakhead) {
-                dprintf(fd, "%18p %7zu %6u %6zu\n", p->d.f,
-                    p->d.total_size, p->d.count, p->d.total_size / p->d.count);
-                if (malloc_leaks == MAP_FAILED ||
-                    i >= MALLOC_PAGESIZE / sizeof(struct malloc_leak))
-                        continue;
-                malloc_leaks[i].f = p->d.f;
-                malloc_leaks[i].total_size = p->d.total_size;
-                malloc_leaks[i].count = p->d.count;
-                i++;
+
+        ulog("Leak report:\n");
+        ulog("                 f     sum      #    avg\n");
+
+        RBT_FOREACH(p, leaktree, leaks) {
+                Dl_info info;
+                const char *caller = p->d.f;
+                const char *object = ".";
+
+                if (caller != NULL) {
+                        if (dladdr(p->d.f, &info) != 0) {
+                                caller -= (uintptr_t)info.dli_fbase;
+                                object = info.dli_fname;
+                        }
+                }
+                ulog("%18p %7zu %6u %6zu addr2line -e %s %p\n",
+                    p->d.f, p->d.total_size, p->d.count,
+                    p->d.total_size / p->d.count,
+                    object, caller);
         }
 }
 
 static void
-dump_chunk(int fd, struct chunk_info *p, void *f, int fromfreelist)
+dump_chunk(struct leaktree* leaks, struct chunk_info *p, void *f,
+    int fromfreelist)
 {
         while (p != NULL) {
-                dprintf(fd, "chunk %18p %18p %4zu %d/%d\n",
-                    p->page, ((p->bits[0] & 1) ? NULL : f),
-                    B2SIZE(p->bucket), p->free, p->total);
+                if (mopts.malloc_verbose)
+                        ulog("chunk %18p %18p %4zu %d/%d\n",
+                            p->page, ((p->bits[0] & 1) ? NULL : f),
+                            B2SIZE(p->bucket), p->free, p->total);
                 if (!fromfreelist) {
                         size_t sz =  B2SIZE(p->bucket);
                         if (p->bits[0] & 1)
-                                putleakinfo(NULL, sz, p->total - p->free);
+                                putleakinfo(leaks, NULL, sz, p->total -
+                                    p->free);
                         else {
-                                putleakinfo(f, sz, 1);
-                                putleakinfo(NULL, sz,
+                                putleakinfo(leaks, f, sz, 1);
+                                putleakinfo(leaks, NULL, sz,
                                     p->total - p->free - 1);
                         }
                         break;
                 }
                 p = LIST_NEXT(p, entries);
-                if (p != NULL)
-                        dprintf(fd, "        ");
+                if (mopts.malloc_verbose && p != NULL)
+                        ulog("       ->");
         }
 }
 
 static void
-dump_free_chunk_info(int fd, struct dir_info *d)
+dump_free_chunk_info(struct dir_info *d, struct leaktree *leaks)
 {
         int i, j, count;
         struct chunk_info *p;
 
-        dprintf(fd, "Free chunk structs:\n");
+        ulog("Free chunk structs:\n");
+        ulog("Bkt) #CI                     page"
+            "                  f size free/n\n");
         for (i = 0; i <= BUCKETS; i++) {
                 count = 0;
                 LIST_FOREACH(p, &d->chunk_info_list[i], entries)
@@ -2345,99 +2393,100 @@ dump_free_chunk_info(int fd, struct dir_info *d)
                         if (p == NULL && count == 0)
                                 continue;
                         if (j == 0)
-                                dprintf(fd, "%3d) %3d ", i, count);
+                                ulog("%3d) %3d ", i, count);
                         else
-                                dprintf(fd, "         ");
+                                ulog("         ");
                         if (p != NULL)
-                                dump_chunk(fd, p, NULL, 1);
+                                dump_chunk(leaks, p, NULL, 1);
                         else
-                                dprintf(fd, "\n");
+                                ulog(".\n");
                 }
         }
 
 }
 
 static void
-dump_free_page_info(int fd, struct dir_info *d)
+dump_free_page_info(struct dir_info *d)
 {
         struct smallcache *cache;
         size_t i, total = 0;
 
-        dprintf(fd, "Cached in small cache:\n");
+        ulog("Cached in small cache:\n");
         for (i = 0; i < MAX_SMALLCACHEABLE_SIZE; i++) {
                 cache = &d->smallcache[i];
                 if (cache->length != 0)
-                        dprintf(fd, "%zu(%u): %u = %zu\n", i + 1, cache->max,
+                        ulog("%zu(%u): %u = %zu\n", i + 1, cache->max,
                             cache->length, cache->length * (i + 1));
                 total += cache->length * (i + 1);
         }
 
-        dprintf(fd, "Cached in big cache: %zu/%zu\n", d->bigcache_used,
+        ulog("Cached in big cache: %zu/%zu\n", d->bigcache_used,
             d->bigcache_size);
         for (i = 0; i < d->bigcache_size; i++) {
                 if (d->bigcache[i].psize != 0)
-                        dprintf(fd, "%zu: %zu\n", i, d->bigcache[i].psize);
+                        ulog("%zu: %zu\n", i, d->bigcache[i].psize);
                 total += d->bigcache[i].psize;
         }
-        dprintf(fd, "Free pages cached: %zu\n", total);
+        ulog("Free pages cached: %zu\n", total);
 }
 
 static void
-malloc_dump1(int fd, int poolno, struct dir_info *d)
+malloc_dump1(int poolno, struct dir_info *d, struct leaktree *leaks)
 {
         size_t i, realsize;
 
-        dprintf(fd, "Malloc dir of %s pool %d at %p\n", __progname, poolno, d);
-        if (d == NULL)
-                return;
-        dprintf(fd, "MT=%d J=%d Fl=%x\n", d->malloc_mt, d->malloc_junk, d->mmap_flag);
-        dprintf(fd, "Region slots free %zu/%zu\n",
-                d->regions_free, d->regions_total);
-        dprintf(fd, "Finds %zu/%zu\n", d->finds, d->find_collisions);
-        dprintf(fd, "Inserts %zu/%zu\n", d->inserts, d->insert_collisions);
-        dprintf(fd, "Deletes %zu/%zu\n", d->deletes, d->delete_moves);
-        dprintf(fd, "Cheap reallocs %zu/%zu\n",
-            d->cheap_reallocs, d->cheap_realloc_tries);
-        dprintf(fd, "Other pool searches %zu/%zu\n",
-            d->other_pool, d->pool_searches);
-        dprintf(fd, "In use %zu\n", d->malloc_used);
-        dprintf(fd, "Guarded %zu\n", d->malloc_guarded);
-        dump_free_chunk_info(fd, d);
-        dump_free_page_info(fd, d);
-        dprintf(fd,
-            "slot)  hash d  type               page                  f "
-            "size [free/n]\n");
+        if (mopts.malloc_verbose) {
+                ulog("Malloc dir of %s pool %d at %p\n", __progname, poolno, d);
+                ulog("MT=%d J=%d Fl=%x\n", d->malloc_mt, d->malloc_junk,
+                    d->mmap_flag);
+                ulog("Region slots free %zu/%zu\n",
+                        d->regions_free, d->regions_total);
+                ulog("Finds %zu/%zu\n", d->finds, d->find_collisions);
+                ulog("Inserts %zu/%zu\n", d->inserts, d->insert_collisions);
+                ulog("Deletes %zu/%zu\n", d->deletes, d->delete_moves);
+                ulog("Cheap reallocs %zu/%zu\n",
+                    d->cheap_reallocs, d->cheap_realloc_tries);
+                ulog("Other pool searches %zu/%zu\n",
+                    d->other_pool, d->pool_searches);
+                ulog("In use %zu\n", d->malloc_used);
+                ulog("Guarded %zu\n", d->malloc_guarded);
+                dump_free_chunk_info(d, leaks);
+                dump_free_page_info(d);
+                ulog("Hash table:\n");
+                ulog("slot)  hash d  type               page                  "
+                    "f size [free/n]\n");
+        }
         for (i = 0; i < d->regions_total; i++) {
                 if (d->r[i].p != NULL) {
                         size_t h = hash(d->r[i].p) &
                             (d->regions_total - 1);
-                        dprintf(fd, "%4zx) #%4zx %zd ",
-                            i, h, h - i);
+                        if (mopts.malloc_verbose)
+                                ulog("%4zx) #%4zx %zd ",
+                                i, h, h - i);
                         REALSIZE(realsize, &d->r[i]);
                         if (realsize > MALLOC_MAXCHUNK) {
-                                putleakinfo(d->r[i].f, realsize, 1);
-                                dprintf(fd,
-                                    "pages %18p %18p %zu\n", d->r[i].p,
-                                    d->r[i].f, realsize);
+                                putleakinfo(leaks, d->r[i].f, realsize, 1);
+                                if (mopts.malloc_verbose)
+                                        ulog("pages %18p %18p %zu\n", d->r[i].p,
+                                        d->r[i].f, realsize);
                         } else
-                                dump_chunk(fd,
+                                dump_chunk(leaks,
                                     (struct chunk_info *)d->r[i].size,
                                     d->r[i].f, 0);
                 }
         }
-        dump_leaks(fd);
-        dprintf(fd, "\n");
+        if (mopts.malloc_verbose)
+                ulog("\n");
 }
 
-void
-malloc_dump(int fd, int poolno, struct dir_info *pool)
+static void
+malloc_dump0(int poolno, struct dir_info *pool, struct leaktree *leaks)
 {
         int i;
         void *p;
         struct region_info *r;
-        int saved_errno = errno;
 
-        if (pool == NULL)
+        if (pool == NULL || pool->r == NULL)
                 return;
         for (i = 0; i < MALLOC_DELAYED_CHUNK_MASK + 1; i++) {
                 p = pool->delayed_chunks[i];
@@ -2449,52 +2498,44 @@ malloc_dump(int fd, int poolno, struct dir_info *pool)
                 free_bytes(pool, r, p);
                 pool->delayed_chunks[i] = NULL;
         }
-        /* XXX leak when run multiple times */
-        RBT_INIT(leaktree, &leakhead);
-        malloc_dump1(fd, poolno, pool);
-        errno = saved_errno;
+        malloc_dump1(poolno, pool, leaks);
 }
-DEF_WEAK(malloc_dump);
 
 void
-malloc_gdump(int fd)
+malloc_dump(void)
 {
         int i;
         int saved_errno = errno;
 
+        /* XXX leak when run multiple times */
+        struct leaktree leaks = RBT_INITIALIZER(&leaks);
+
         for (i = 0; i < mopts.malloc_mutexes; i++)
-                malloc_dump(fd, i, mopts.malloc_pool[i]);
+                malloc_dump0(i, mopts.malloc_pool[i], &leaks);
 
+        dump_leaks(&leaks);
+        ulog("\n");
         errno = saved_errno;
 }
-DEF_WEAK(malloc_gdump);
+DEF_WEAK(malloc_dump);
 
 static void
 malloc_exit(void)
 {
-        int save_errno = errno, fd;
-        unsigned i;
-
-        fd = open("malloc.out", O_RDWR|O_APPEND);
-        if (fd != -1) {
-                dprintf(fd, "******** Start dump %s *******\n", __progname);
-                dprintf(fd,
-                    "M=%u I=%d F=%d U=%d J=%d R=%d X=%d C=%d cache=%u "
-                    "G=%zu\n",
-                    mopts.malloc_mutexes,
-                    mopts.internal_funcs, mopts.malloc_freecheck,
-                    mopts.malloc_freeunmap, mopts.def_malloc_junk,
-                    mopts.malloc_realloc, mopts.malloc_xmalloc,
-                    mopts.chunk_canaries, mopts.def_maxcache,
-                    mopts.malloc_guard);
-
-                for (i = 0; i < mopts.malloc_mutexes; i++)
-                        malloc_dump(fd, i, mopts.malloc_pool[i]);
-                dprintf(fd, "******** End dump %s *******\n", __progname);
-                close(fd);
-        } else
-                dprintf(STDERR_FILENO,
-                    "malloc() warning: Couldn't dump stats\n");
+        int save_errno = errno;
+
+        ulog("******** Start dump %s *******\n", __progname);
+        ulog("M=%u I=%d F=%d U=%d J=%d R=%d X=%d C=%d cache=%u "
+            "G=%zu\n",
+            mopts.malloc_mutexes,
+            mopts.internal_funcs, mopts.malloc_freecheck,
+            mopts.malloc_freeunmap, mopts.def_malloc_junk,
+            mopts.malloc_realloc, mopts.malloc_xmalloc,
+            mopts.chunk_canaries, mopts.def_maxcache,
+            mopts.malloc_guard);
+
+        malloc_dump();
+        ulog("******** End dump %s *******\n", __progname);
         errno = save_errno;
 }