From 768db4f5ca93d4dad1f5104e1a3676c40ad85a55 Mon Sep 17 00:00:00 2001 From: Jacob Garber Date: Tue, 25 Jun 2019 11:59:59 -0600 Subject: libpayload/libc: Correct strlcat return value The documented return value for strlcat is horribly wrong, as is the return value itself. It should not return the number of appended bytes, but rather the length of the concatenated string. From the man page: The strlcpy() and strlcat() functions return the total length of the string they tried to create. For strlcpy() that means the length of src. For strlcat() that means the initial length of dst plus the length of src. While this may seem somewhat confusing, it was done to make truncation detection simple. This change is more likely to fix existing code than break it, since anyone who uses the return value of strlcat will almost certainly rely on the standard behaviour rather than investigate coreboot's source code to see that we have a quirky version. Change-Id: I4421305af85bce88d12d6fdc2eea6807ccdcf449 Signed-off-by: Jacob Garber Reviewed-on: https://review.coreboot.org/c/coreboot/+/33787 Tested-by: build bot (Jenkins) Reviewed-by: Julius Werner --- payloads/libpayload/libc/string.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'payloads') diff --git a/payloads/libpayload/libc/string.c b/payloads/libpayload/libc/string.c index 6c257cbdaa..9a5a1ea4c1 100644 --- a/payloads/libpayload/libc/string.c +++ b/payloads/libpayload/libc/string.c @@ -249,7 +249,7 @@ char *strncat(char *d, const char *s, size_t n) * @param d The destination string. * @param s The source string. * @param n d will have at most n-1 characters (plus NUL) after invocation. - * @return A pointer to the destination string. + * @return The total length of the concatenated string. */ size_t strlcat(char *d, const char *s, size_t n) { @@ -264,7 +264,7 @@ size_t strlcat(char *d, const char *s, size_t n) p[i] = s[i]; p[i] = '\0'; - return max; + return sl + dl; } /** -- cgit v1.2.3