sparc64: Replace all non-returning strlcpy with strscpy

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] KSPP#89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230530163001.985256-1-azeemshaikh38@gmail.com

Author: azeemshaikh38

arch/sparc/kernel/ioport.c

@@ -191,7 +191,7 @@ static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
 		tack += sizeof (struct resource);
 	}
 
-	strlcpy(tack, name, XNMLN+1);
+	strscpy(tack, name, XNMLN+1);
 	res->name = tack;
 
 	va = _sparc_ioremap(res, busno, phys, size);

arch/sparc/kernel/setup_32.c

@@ -302,7 +302,7 @@ void __init setup_arch(char **cmdline_p)
 
 	/* Initialize PROM console and command line. */
 	*cmdline_p = prom_getbootargs();
-	strlcpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
+	strscpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
 	parse_early_param();
 
 	boot_flags_init(*cmdline_p);

arch/sparc/kernel/setup_64.c

@@ -636,7 +636,7 @@ void __init setup_arch(char **cmdline_p)
 {
 	/* Initialize PROM console and command line. */
 	*cmdline_p = prom_getbootargs();
-	strlcpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
+	strscpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
 	parse_early_param();
 
 	boot_flags_init(*cmdline_p);

arch/sparc/prom/bootstr_32.c

@@ -52,7 +52,7 @@ prom_getbootargs(void)
 		 * V3 PROM cannot supply as with more than 128 bytes
 		 * of an argument. But a smart bootstrap loader can.
 		 */
-		strlcpy(barg_buf, *romvec->pv_v2bootargs.bootargs, sizeof(barg_buf));
+		strscpy(barg_buf, *romvec->pv_v2bootargs.bootargs, sizeof(barg_buf));
 		break;
 	default:
 		break;