Commit 8790cc29 authored by Thorsten Blum's avatar Thorsten Blum Committed by Daniel Thompson (RISCstar)
Browse files

kdb: Replace deprecated strcpy() with memmove() in vkdb_printf() 

strcpy() is deprecated and its behavior is undefined when the source and
destination buffers overlap. Use memmove() instead to avoid any
undefined behavior.

Adjust comments for clarity.

Link: https://github.com/KSPP/linux/issues/88


Fixes: 5d5314d6 ("kdb: core for kgdb back end (1 of 2)")
Reviewed-by: default avatarDouglas Anderson <dianders@chromium.org>
Signed-off-by: default avatarThorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: default avatarDaniel Thompson (RISCstar) <danielt@kernel.org>
parent d4be3238

kernel/debug/kdb/kdb_io.c

+8 −6
Original line number Diff line number Diff line
@@ -714,8 +714,8 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap) 
		 * it, depending on the results of the search.

		 */

		cp++;	 	     /* to byte after the newline */

		replaced_byte = *cp; /* remember what/where it was */

		cphold = cp;

		replaced_byte = *cp; /* remember what it was */

		cphold = cp;	     /* remember where it was */

		*cp = '\0';	     /* end the string for our search */



		/*
@@ -732,8 +732,9 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap) 
			 * Shift the buffer left.

			 */

			*cphold = replaced_byte;

			strcpy(kdb_buffer, cphold);

			len = strlen(kdb_buffer);

			len = strlen(cphold);

			/* Use memmove() because the buffers overlap */

			memmove(kdb_buffer, cphold, len + 1);

			next_avail = kdb_buffer + len;

			size_avail = sizeof(kdb_buffer) - len;

			goto kdb_print_out;
@@ -872,8 +873,9 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap) 
	 */

	if (kdb_grepping_flag && !suspend_grep) {

		*cphold = replaced_byte;

		strcpy(kdb_buffer, cphold);

		len = strlen(kdb_buffer);

		len = strlen(cphold);

		/* Use memmove() because the buffers overlap */

		memmove(kdb_buffer, cphold, len + 1);

		next_avail = kdb_buffer + len;

		size_avail = sizeof(kdb_buffer) - len;

	}