From b0f55f2a1a295c364be012e82dbab079a2454006 Mon Sep 17 00:00:00 2001
From: Joern Rennecke <joern.rennecke@embecosm.com>
Date: Sat, 24 Aug 2013 12:03:06 +0530
Subject: [PATCH] ARC: [lib] strchr breakage in Big-endian configuration
For a search buffer, 2 byte aligned, strchr() was returning pointer
outside of buffer (buf - 1)
------------->8----------------
// Input buffer (default 4 byte aigned)
char *buffer = "1AA_";
// actual search start (to mimick 2 byte alignment)
char *current_line = &(buffer[2]);
// Character to search for
char c = 'A';
char *c_pos = strchr(current_line, c);
printf("%s\n", c_pos) --> 'AA_' as oppose to 'A_'
------------->8----------------
Reported-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Debugged-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Cc: <stable@vger.kernel.org> # [3.9 and 3.10]
Cc: Noam Camus <noamc@ezchip.com>
Signed-off-by: Joern Rennecke <joern.rennecke@embecosm.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
arch/arc/lib/strchr-700.S | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/arch/arc/lib/strchr-700.S b/arch/arc/lib/strchr-700.S
index 99c10475d477..9c548c7cf001 100644
--- a/arch/arc/lib/strchr-700.S
+++ b/arch/arc/lib/strchr-700.S
@@ -39,9 +39,18 @@ ARC_ENTRY strchr
ld.a r2,[r0,4]
sub r12,r6,r7
bic r12,r12,r6
+#ifdef __LITTLE_ENDIAN__
and r7,r12,r4
breq r7,0,.Loop ; For speed, we want this branch to be unaligned.
b .Lfound_char ; Likewise this one.
+#else
+ and r12,r12,r4
+ breq r12,0,.Loop ; For speed, we want this branch to be unaligned.
+ lsr_s r12,r12,7
+ bic r2,r7,r6
+ b.d .Lfound_char_b
+ and_s r2,r2,r12
+#endif
; /* We require this code address to be unaligned for speed... */
.Laligned:
ld_s r2,[r0]
@@ -95,6 +104,7 @@ ARC_ENTRY strchr
lsr r7,r7,7
bic r2,r7,r6
+.Lfound_char_b:
norm r2,r2
sub_s r0,r0,4
asr_s r2,r2,3