[U-Boot] [PATCH] lib: fix return codes when CONFIG_SYS_VSNPRINTF is enabled

[Darwin Rambo]

When CONFIG_SYS_VSNPRINTF is enabled, it protects print operations
such as sprintf, snprintf, vsnprintf, etc., from buffer overflows.
But vsnprintf_internal includes the terminating NULL character in
the calculation of number of characters written. This affects sprintf
and snprintf return values. Fix this issue by setting pointer 'str'
back to the location of the '\0'.

Signed-off-by: Darwin Rambo <drambo at broadcom.com>
Reviewed-by: Steve Rae <srae at broadcom.com>
---
 lib/vsprintf.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 82e5c13..60874da 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -750,6 +750,7 @@ repeat:
 		ADDCH(str, '\0');
 		if (str > end)
 			end[-1] = '\0';
+		--str;
 	}
 #else
 	*str = '\0';
-- 
1.7.9.5