blob: f6888277b197b7d717179e7c2fb53e9014bd71bf [file] [log] [blame]
From: Arnd Bergmann <arnd@arndb.de>
Subject: test_hexdump: avoid string truncation warning
Date: Tue, 9 Apr 2024 16:00:54 +0200
gcc can warn when a string is too long to fit into the strncpy()
destination buffer, as it is here depending on the function arguments:
inlined from 'test_hexdump_prepare_test.constprop' at /home/arnd/arm-soc/lib/test_hexdump.c:116:3:
include/linux/fortify-string.h:108:33: error: '__builtin_strncpy' output truncated copying between 0 and 32 bytes from a string of length 32 [-Werror=stringop-truncation]
108 | #define __underlying_strncpy __builtin_strncpy
| ^
include/linux/fortify-string.h:187:16: note: in expansion of macro '__underlying_strncpy'
187 | return __underlying_strncpy(p, q, size);
| ^~~~~~~~~~~~~~~~~~~~
The intention here is to copy exactly 'l' bytes without any padding or
NUL-termination, so the most logical change is to use memcpy(), just as
a previous change adapted the other output from strncpy() to memcpy().
Link: https://lkml.kernel.org/r/20240409140059.3806717-2-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Justin Stitt <justinstitt@google.com>
Cc: Alexey Starikovskiy <astarikovskiy@suse.de>
Cc: Bob Moore <robert.moore@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Len Brown <lenb@kernel.org>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Richard Russon (FlatCap)" <ldm@flatcap.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
lib/test_hexdump.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/lib/test_hexdump.c~test_hexdump-avoid-string-truncation-warning
+++ a/lib/test_hexdump.c
@@ -113,7 +113,7 @@ static void __init test_hexdump_prepare_
*p++ = ' ';
} while (p < test + rs * 2 + rs / gs + 1);
- strncpy(p, data_a, l);
+ memcpy(p, data_a, l);
p += l;
}
_