[procps-ng] - Avoid segfaults when reading zero bytes - file2str (#951391)

[Jaromír Cápík]

commit 61e5068603aa005811e271c8198c4e3c44c3b6c8
Author: Jaromir Capik <jcapik at redhat.com>
Date:   Tue Apr 16 17:18:25 2013 +0200

    - Avoid segfaults when reading zero bytes - file2str (#951391)

 ...ps-ng-3.3.7-segv-file2str-read-zero-bytes.patch |   41 ++++++++++++++++++++
 procps-ng.spec                                     |    7 +++-
 2 files changed, 47 insertions(+), 1 deletions(-)
---
diff --git a/procps-ng-3.3.7-segv-file2str-read-zero-bytes.patch b/procps-ng-3.3.7-segv-file2str-read-zero-bytes.patch
new file mode 100644
index 0000000..3cfad63
--- /dev/null
+++ b/procps-ng-3.3.7-segv-file2str-read-zero-bytes.patch
@@ -0,0 +1,41 @@
+diff --git a/proc/readproc.c b/proc/readproc.c
+--- procps-ng-3.3.7.orig/proc/readproc.c	2013-03-25 11:50:21.000000000 +0100
++++ procps-ng-3.3.7/proc/readproc.c	2013-03-26 17:50:54.860228114 +0100
+@@ -534,28 +534,32 @@
+ 
+ static int file2str(const char *directory, const char *what, struct utlbuf_s *ub) {
+  #define readMAX  4096
+- #define buffMIN (tot_read + num + 1)  // +1 for the '\0' delimiter
++ #define buffMIN (tot_read + num + 1)       // +1 for the '\0' delimiter
++ #define buffGRW (30 + (buffMIN * 5) / 4)   // grow by more than 25%
+     char path[PROCPATHLEN], chunk[readMAX];
+-    int fd, num, tot_read = 0;
++    int fd, num, eof = 0, tot_read = 0;
+ 
+     /* on first use we preallocate a buffer of minimum size to emulate
+        former 'local static' behavior -- even if this read fails, that
+-       buffer will likely soon be used for another sudirectory anyway */
++       buffer will likely soon be used for another subdirectory anyway */
+     if (ub->buf) ub->buf[0] = '\0';
+     else ub->buf = xcalloc((ub->siz = readMAX));
+     sprintf(path, "%s/%s", directory, what);
+     if (-1 == (fd = open(path, O_RDONLY, 0))) return -1;
+-    while (0 < (num = read(fd, chunk, readMAX))) {
++    while (!eof && 0 < (num = read(fd, chunk, readMAX))) {
+         if (ub->siz < buffMIN)
+-            ub->buf = xrealloc(ub->buf, (ub->siz = buffMIN));
++            ub->buf = xrealloc(ub->buf, (ub->siz = buffGRW));
+         memcpy(ub->buf + tot_read, chunk, num);
+         tot_read += num;
++        eof = (num < readMAX);
+     };
+     ub->buf[tot_read] = '\0';
+     close(fd);
++    if (unlikely(tot_read < 1)) return -1;
+     return tot_read;
+  #undef readMAX
+  #undef buffMIN
++ #undef buffGRW
+ }
+ 
+ static char** file2strvec(const char* directory, const char* what) {
diff --git a/procps-ng.spec b/procps-ng.spec
index 1220890..3ceab9f 100644
--- a/procps-ng.spec
+++ b/procps-ng.spec
@@ -3,7 +3,7 @@
 Summary: System and process monitoring utilities
 Name: procps-ng
 Version: 3.3.7
-Release: 2%{?dist}
+Release: 3%{?dist}
 License: GPLv2+ and LGPLv2+
 Group: Applications/System
 URL: https://sourceforge.net/projects/procps-ng/
@@ -11,6 +11,7 @@ URL: https://sourceforge.net/projects/procps-ng/
 Source: http://downloads.sourceforge.net/%{name}/%{name}-%{version}.tar.xz
 
 Patch0: procps-ng-3.3.7-testsuite-reverting-bogus-commit-unix-exp.patch
+Patch1: procps-ng-3.3.7-segv-file2str-read-zero-bytes.patch
 
 Requires(post): /sbin/ldconfig
 Requires(postun): /sbin/ldconfig
@@ -67,6 +68,7 @@ System and process monitoring utilities development headers
 %setup -q -n %{name}-%{version}
 
 %patch0 -p1
+%patch1 -p1
 
 %build
 # The following stuff is needed for git archives only
@@ -129,6 +131,9 @@ mkdir -p %{buildroot}%{_sysconfdir}/sysctl.d
 %{_includedir}/proc
 
 %changelog
+* Tue Apr 16 2013 Jaromir Capik <jcapik at redhat.com> - 3.3.7-3
+- Avoid segfaults when reading zero bytes - file2str (#951391)
+
 * Mon Apr 15 2013 Jaromir Capik <jcapik at redhat.com> - 3.3.7-2
 - Moving libprocps.pc to the devel subpackage (#951726)