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-rw-r--r--ChangeLog8
-rw-r--r--string/test-memchr.c6
-rw-r--r--sysdeps/i386/i686/multiarch/memchr-sse2.S2
3 files changed, 15 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index 24908d0e21..71e72722ad 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2017-03-29  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
+
+	[BZ# 21182]
+	* string/test-memchr.c (do_test): Add BZ#21182 checks for address
+	near end of a page.
+	* sysdeps/i386/i686/multiarch/memchr-sse2.S (__memchr): Fix
+	overflow calculation.
+
 2017-03-28  Steve Ellcey  <sellcey@caviumnetworks.com>
 
 	* benchtests/bench-memcpy-random.c (TEST_NAME): Change to memcpy.
diff --git a/string/test-memchr.c b/string/test-memchr.c
index 2403c9242b..669e092e7d 100644
--- a/string/test-memchr.c
+++ b/string/test-memchr.c
@@ -210,6 +210,12 @@ test_main (void)
       do_test (0, i, i + 1, i + 1, 0);
     }
 
+  /* BZ#21182 - wrong overflow calculation for i686 implementation
+     with address near end of the page.  */
+  for (i = 2; i < 16; ++i)
+    /* page_size is in fact getpagesize() * 2.  */
+    do_test (page_size / 2 - i, i, i, 1, 0x9B);
+
   do_random_tests ();
   return ret;
 }
diff --git a/sysdeps/i386/i686/multiarch/memchr-sse2.S b/sysdeps/i386/i686/multiarch/memchr-sse2.S
index 910679cfc0..e41f324a77 100644
--- a/sysdeps/i386/i686/multiarch/memchr-sse2.S
+++ b/sysdeps/i386/i686/multiarch/memchr-sse2.S
@@ -117,7 +117,6 @@ L(crosscache):
 
 # ifndef USE_AS_RAWMEMCHR
 	jnz	L(match_case2_prolog1)
-	lea	-16(%edx), %edx
         /* Calculate the last acceptable address and check for possible
            addition overflow by using satured math:
            edx = ecx + edx
@@ -125,6 +124,7 @@ L(crosscache):
 	add	%ecx, %edx
 	sbb	%eax, %eax
 	or	%eax, %edx
+	sub	$16, %edx
 	jbe	L(return_null)
 	lea	16(%edi), %edi
 # else