Fix problem with brk(). Thanks to Paull Mackerras for the patch.

Added a regression test for it.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@2619

diff --git a/coregrind/vg_syscalls.c b/coregrind/vg_syscalls.c
index 0d87da856e2ac55de928e271c59a3704c4908bd2..c279aaee39ca787b902fe4c8cdeea31e685e1b31 100644 (file)
--- a/coregrind/vg_syscalls.c
+++ b/coregrind/vg_syscalls.c
@@ -900,6 +900,8 @@ static Addr do_brk(Addr newbrk)
    Addr ret = VG_(brk_limit);
    static const Bool debug = False;
    Segment *seg;
+   Addr current, newaddr;
+
 
    if (debug)
       VG_(printf)("do_brk: brk_base=%p brk_limit=%p newbrk=%p\n",
@@ -922,9 +924,9 @@ static Addr do_brk(Addr newbrk)
    if (seg != NULL && newbrk > seg->addr)
       return VG_(brk_limit);
 
-   if (PGROUNDDN(newbrk) != PGROUNDDN(VG_(brk_limit))) {
-      Addr current = PGROUNDUP(VG_(brk_limit));
-      Addr newaddr = PGROUNDUP(newbrk);
+   current = PGROUNDUP(VG_(brk_limit));
+   newaddr = PGROUNDUP(newbrk);
+   if (newaddr != current) {
 
       /* new brk in a new page - fix the mappings */
       if (newbrk > VG_(brk_limit)) {

diff --git a/memcheck/tests/Makefile.am b/memcheck/tests/Makefile.am
index 4d3035ed3ba10b029b051d982ad21364c2f55b22..a8fccb8c5520b057ce4330ad2bf62bde7b94f1ae 100644 (file)
--- a/memcheck/tests/Makefile.am
+++ b/memcheck/tests/Makefile.am
@@ -18,6 +18,7 @@ EXTRA_DIST = $(noinst_SCRIPTS) \
        badloop.stderr.exp badloop.vgtest \
        badrw.stderr.exp badrw.vgtest \
        brk.stderr.exp brk.vgtest \
+       brk2.stderr.exp brk2.vgtest \
        buflen_check.stderr.exp buflen_check.vgtest \
        clientperm.stderr.exp \
        clientperm.stdout.exp clientperm.vgtest \
@@ -77,7 +78,7 @@ EXTRA_DIST = $(noinst_SCRIPTS) \
        zeropage.stderr.exp zeropage.vgtest
 
 check_PROGRAMS = \
-       badaddrvalue badfree badjump badloop badrw brk buflen_check \
+       badaddrvalue badfree badjump badloop badrw brk brk2 buflen_check \
        clientperm custom_alloc \
        doublefree error_counts errs1 exitprog execve execve2 \
        fpeflags fprw fwrite inits inline \
@@ -100,6 +101,7 @@ badjump_SOURCES     = badjump.c
 badloop_SOURCES        = badloop.c
 badrw_SOURCES          = badrw.c
 brk_SOURCES            = brk.c
+brk2_SOURCES           = brk2.c
 buflen_check_SOURCES   = buflen_check.c
 clientperm_SOURCES     = clientperm.c
 custom_alloc_SOURCES   = custom_alloc.c

diff --git a/memcheck/tests/brk2.c b/memcheck/tests/brk2.c
new file mode 100644 (file)
index 0000000..3a88133
--- /dev/null
+++ b/memcheck/tests/brk2.c
@@ -0,0 +1,25 @@
+#include <stdio.h>
+#include <unistd.h>
+
+#define MAX 3000
+
+// At one time, this was causing a seg fault within Valgrind -- it was when
+// extending the brk segment onto a new page.  Fixed in vg_syscalls.c 1.129.
+
+int main () {
+  char* ptr;
+  int i;
+
+  for (i=0; i<MAX; i++) {
+    ptr = sbrk(1);
+
+    if (ptr == (void*)-1) {
+      printf ("sbrk() failed!\n");
+      return 0;
+    }
+
+    *ptr = 0;
+  }
+
+  return 0;
+} 

diff --git a/memcheck/tests/brk2.stderr.exp b/memcheck/tests/brk2.stderr.exp
new file mode 100644 (file)
index 0000000..c4aa6f0
--- /dev/null
+++ b/memcheck/tests/brk2.stderr.exp
@@ -0,0 +1,7 @@
+
+
+ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
+malloc/free: in use at exit: 0 bytes in 0 blocks.
+malloc/free: 0 allocs, 0 frees, 0 bytes allocated.
+For a detailed leak analysis,  rerun with: --leak-check=yes
+For counts of detected errors, rerun with: -v

diff --git a/memcheck/tests/brk2.vgtest b/memcheck/tests/brk2.vgtest
new file mode 100644 (file)
index 0000000..951b3fa
--- /dev/null
+++ b/memcheck/tests/brk2.vgtest
@@ -0,0 +1 @@
+prog: brk2