shred: don't infloop upon negative size

* src/shred.c (main): With the preceding change, shred -s-2 FILE
would write 64KB blocks forever -- or until disk full. This change
makes shred reject a negative size.
* tests/misc/shred-negative.sh: New file.
* tests/local.mk (all_tests): Add it.

diff --git a/src/shred.c b/src/shred.c
index f4347e002a18741b547596b60095695684a791d6..bd88e383170ffe509b3c8e0b30faeb5f71ad1468 100644 (file)
--- a/src/shred.c
+++ b/src/shred.c
@@ -1256,8 +1256,8 @@ main (int argc, char **argv)
 
         case 's':
           {
-            intmax_t tmp;
-            if ((xstrtoimax (optarg, NULL, 0, &tmp, "cbBkKMGTPEZY0")
+            uintmax_t tmp;
+            if ((xstrtoumax (optarg, NULL, 0, &tmp, "cbBkKMGTPEZY0")
                  != LONGINT_OK)
                 || OFF_T_MAX < tmp)
               {

diff --git a/tests/local.mk b/tests/local.mk
index 5286bfb342b16282bb10e669c8dda1dec5f0a363..cd7da5b2fd2ab27f62f075421ba3c7b08573bca9 100644 (file)
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -313,6 +313,7 @@ all_tests =                                 \
   tests/misc/sha384sum.pl                      \
   tests/misc/sha512sum.pl                      \
   tests/misc/shred-exact.sh                    \
+  tests/misc/shred-negative.sh                 \
   tests/misc/shred-passes.sh                   \
   tests/misc/shred-remove.sh                   \
   tests/misc/shuf.sh                           \

diff --git a/tests/misc/shred-negative.sh b/tests/misc/shred-negative.sh
new file mode 100755 (executable)
index 0000000..86cbf3e
--- /dev/null
+++ b/tests/misc/shred-negative.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+# Exercise shred -s-3 FILE
+
+# Copyright (C) 2014 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ shred
+
+echo 'shred: -2: invalid file size' > exp || framework_failure_
+echo 1234 > f || framework_failure_
+
+shred -s-2 f 2>err && fail=1
+compare exp err || fail=1
+
+Exit $fail