summaryrefslogtreecommitdiff
path: root/stdio-common/tst-sscanf.c
diff options
context:
space:
mode:
authorPaul Pluzhnikov <ppluzhnikov@google.com>2015-02-06 00:30:42 -0500
committerCarlos O'Donell <carlos@systemhalted.org>2015-02-06 00:34:51 -0500
commit5bd80bfe9ca0d955bfbbc002781bc7b01b6bcb06 (patch)
treea77a8efbf88a4eed15cfefe4e5d570d380985c1c /stdio-common/tst-sscanf.c
parent04cb913ddf67ac90da274dd32b6ceafd57ca36ca (diff)
downloadglibc-5bd80bfe9ca0d955bfbbc002781bc7b01b6bcb06.tar.gz
CVE-2015-1472: wscanf allocates too little memory
BZ #16618 Under certain conditions wscanf can allocate too little memory for the to-be-scanned arguments and overflow the allocated buffer. The implementation now correctly computes the required buffer size when using malloc. A regression test was added to tst-sscanf.
Diffstat (limited to 'stdio-common/tst-sscanf.c')
-rw-r--r--stdio-common/tst-sscanf.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/stdio-common/tst-sscanf.c b/stdio-common/tst-sscanf.c
index aece3f2f29..8a2eb9e39c 100644
--- a/stdio-common/tst-sscanf.c
+++ b/stdio-common/tst-sscanf.c
@@ -233,5 +233,38 @@ main (void)
}
}
+ /* BZ #16618
+ The test will segfault during SSCANF if the buffer overflow
+ is not fixed. The size of `s` is such that it forces the use
+ of malloc internally and this triggers the incorrect computation.
+ Thus the value for SIZE is arbitrariy high enough that malloc
+ is used. */
+ {
+#define SIZE 131072
+ CHAR *s = malloc ((SIZE + 1) * sizeof (*s));
+ if (s == NULL)
+ abort ();
+ for (size_t i = 0; i < SIZE; i++)
+ s[i] = L('0');
+ s[SIZE] = L('\0');
+ int i = 42;
+ /* Scan multi-digit zero into `i`. */
+ if (SSCANF (s, L("%d"), &i) != 1)
+ {
+ printf ("FAIL: bug16618: SSCANF did not read one input item.\n");
+ result = 1;
+ }
+ if (i != 0)
+ {
+ printf ("FAIL: bug16618: Value of `i` was not zero as expected.\n");
+ result = 1;
+ }
+ free (s);
+ if (result != 1)
+ printf ("PASS: bug16618: Did not crash.\n");
+#undef SIZE
+ }
+
+
return result;
}