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Upstream-Status: Backport 3.4.0
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
---
From 493574ad1f4f56dd63097a652b87c25c507ce99c Mon Sep 17 00:00:00 2001
From: Etienne Carriere <etienne.carriere@linaro.org>
Date: Fri, 21 Dec 2018 15:36:00 +0100
Subject: [PATCH] xtest: prevent unexpected build warning with strncpy
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
This change modifies adbg_run.c to prevent a false positive
warning reported by GCC 8.2 on usage of strncpy():
build/optee_test/host/xtest/adbg/src/adbg_run.c: In function ‘Do_ADBG_AppendToSuite’:
build/optee_test/host/xtest/adbg/src/adbg_run.c:103:3: error: ‘strncpy’ specified bound depends on the length of the source argument [-Werror=stringop-overflow=]
strncpy(p, Source_p->SuiteID_p, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
build/optee_test/host/xtest/adbg/src/adbg_run.c:88:9: note: length computed here
size = strlen(Source_p->SuiteID_p);
^~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
From [1]:
Using strncpy Safely
In general, it is not possible to avoid string truncation by strncpy
except by sizing the destination to be at least a byte larger than
the length of the source string. With that approach, however, using
strncpy becomes unnecessary and the function can be avoided in favor
of other APIs such as strcpy or (less preferably) memcpy. Much has
been written about the problems with strncpy and we recommend to
avoid it whenever possible. It is, however, worth keeping in mind
that unlike other standard string-handling functions, strncpy always
writes exactly as many characters as specified by the third argument;
if the source string is shorter, the function fills the remaining
bytes with NULs.
This change prefers using a snprintf() as used in the alternate
instruction block of the strncpy() call.
[1] https://developers.redhat.com/blog/2018/05/24/detecting-string-truncation-with-gcc-8/
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Simon Hughes <simon.hughes@arm.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
---
host/xtest/adbg/src/adbg_run.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/host/xtest/adbg/src/adbg_run.c b/host/xtest/adbg/src/adbg_run.c
index 406e429..2739db5 100644
--- a/host/xtest/adbg/src/adbg_run.c
+++ b/host/xtest/adbg/src/adbg_run.c
@@ -100,7 +100,7 @@ int Do_ADBG_AppendToSuite(
snprintf(p, size, "%s+%s", Dest_p->SuiteID_p,
Source_p->SuiteID_p);
else
- strncpy(p, Source_p->SuiteID_p, size);
+ snprintf(p, size, "%s", Source_p->SuiteID_p);
free((void *)Dest_p->SuiteID_p);
Dest_p->SuiteID_p = p;
--
2.7.4
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