From: Raphael Moreira Zinsly <rzinsly@linux.ibm.com>
To: libc-alpha@sourceware.org
Cc: murphyp@linux.ibm.com, Raphael Moreira Zinsly <rzinsly@linux.ibm.com>
Subject: [PATCH v9] string: test strncasecmp and strncpy near page boundaries
Date: Fri, 21 Aug 2020 12:10:22 -0300 [thread overview]
Message-ID: <20200821151022.12320-1-rzinsly@linux.ibm.com> (raw)
Changes since v8:
- Title reworded.
- Fixed spelling on commit message.
string/test-strncpy.c
- Removed unnecessary parenthesis.
- Changed 'n' to be maxoffset + (maxoffset - off2)
in order to always touch the s2 page boundary.
--- >8 ---
Add tests to check if strings placed at page boundaries are
handled correctly by strncasecmp and strncpy similar to tests
for strncmp and strnlen.
---
string/test-strncasecmp.c | 43 +++++++++++++++++++++++++++++++++++++++
string/test-strncpy.c | 35 +++++++++++++++++++++++++++++++
2 files changed, 78 insertions(+)
diff --git a/string/test-strncasecmp.c b/string/test-strncasecmp.c
index 6a9c27beae..502222ed1d 100644
--- a/string/test-strncasecmp.c
+++ b/string/test-strncasecmp.c
@@ -137,6 +137,48 @@ do_test (size_t align1, size_t align2, size_t n, size_t len, int max_char,
do_one_test (impl, s1, s2, n, exp_result);
}
+static void
+do_page_tests (void)
+{
+ char *s1, *s2;
+ int exp_result;
+ const size_t maxoffset = 64;
+
+ s1 = (char *) buf1 + BUF1PAGES * page_size - maxoffset;
+ memset (s1, 'a', maxoffset - 1);
+ s1[maxoffset - 1] = '\0';
+
+ s2 = (char *) buf2 + page_size - maxoffset;
+ memset (s2, 'a', maxoffset - 1);
+ s2[maxoffset - 1] = '\0';
+
+ /* At this point s1 and s2 point to distinct memory regions containing
+ "aa..." with size of 63 plus '\0'. Also, both strings are bounded to a
+ page with read/write access and the next page is protected with PROT_NONE
+ (meaning that any access outside of the page regions will trigger an
+ invalid memory access).
+
+ The loop checks for all possible offsets up to maxoffset for both
+ inputs with a size larger than the string (so memory access outside
+ the expected memory regions might trigger invalid access). */
+
+ for (size_t off1 = 0; off1 < maxoffset; off1++)
+ {
+ for (size_t off2 = 0; off2 < maxoffset; off2++)
+ {
+ exp_result = (off1 == off2)
+ ? 0
+ : off1 < off2
+ ? 'a'
+ : -'a';
+
+ FOR_EACH_IMPL (impl, 0)
+ check_result (impl, s1 + off1, s2 + off2, maxoffset + 1,
+ exp_result);
+ }
+ }
+}
+
static void
do_random_tests (void)
{
@@ -334,6 +376,7 @@ test_locale (const char *locale)
}
do_random_tests ();
+ do_page_tests ();
}
int
diff --git a/string/test-strncpy.c b/string/test-strncpy.c
index c978753ad8..e902c1764e 100644
--- a/string/test-strncpy.c
+++ b/string/test-strncpy.c
@@ -155,6 +155,40 @@ do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char)
do_one_test (impl, s2, s1, len, n);
}
+static void
+do_page_tests (void)
+{
+ CHAR *s1, *s2;
+ const size_t maxoffset = 64;
+
+ /* Put s1 at the maxoffset from the edge of buf1's last page. */
+ s1 = (CHAR *) buf1 + BUF1PAGES * page_size / sizeof(CHAR) - maxoffset;
+ /* s2 needs room to put a string with size of maxoffset + 1 at s2 +
+ (maxoffset - 1). */
+ s2 = (CHAR *) buf2 + page_size / sizeof(CHAR) - maxoffset * 2;
+
+ MEMSET (s1, 'a', maxoffset - 1);
+ s1[maxoffset - 1] = '\0';
+
+ /* Both strings are bounded to a page with read/write access and the next
+ page is protected with PROT_NONE (meaning that any access outside of the
+ page regions will trigger an invalid memory access).
+
+ The loop copies the string s1 for all possible offsets up to maxoffset
+ for both inputs with a size larger than s1 (so memory access outside the
+ expected memory regions might trigger invalid access). */
+
+ for (size_t off1 = 0; off1 < maxoffset; off1++)
+ {
+ for (size_t off2 = 0; off2 < maxoffset; off2++)
+ {
+ FOR_EACH_IMPL (impl, 0)
+ do_one_test (impl, s2 + off2, s1 + off1, maxoffset - off1 - 1,
+ maxoffset + (maxoffset - off2));
+ }
+ }
+}
+
static void
do_random_tests (void)
{
@@ -317,6 +351,7 @@ test_main (void)
}
do_random_tests ();
+ do_page_tests ();
return ret;
}
--
2.26.2
next reply other threads:[~2020-08-21 15:10 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-21 15:10 Raphael Moreira Zinsly [this message]
2020-08-24 21:31 ` Paul E Murphy
2020-08-25 19:45 ` Lucas A. M. Magalhaes
2020-08-26 20:58 ` Paul E Murphy
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