[PATCH 4.4 08/56] staging/rts5208: Fix read overflow in memcpy

From: Greg Kroah-Hartman
Date: Mon Sep 17 2018 - 18:43:48 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Daniel Micay <danielmicay@xxxxxxxxx>

commit 88a5b39b69ab1828fd4130e2baadd184109cea69 upstream.

Noticed by FORTIFY_SOURCE, this swaps memcpy() for strncpy() to zero-value
fill the end of the buffer instead of over-reading a string from .rodata.

Signed-off-by: Daniel Micay <danielmicay@xxxxxxxxx>
[kees: wrote commit log]
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Wayne Porter <wporter82@xxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>

---
drivers/staging/rts5208/rtsx_scsi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/staging/rts5208/rtsx_scsi.c
+++ b/drivers/staging/rts5208/rtsx_scsi.c
@@ -536,7 +536,7 @@ static int inquiry(struct scsi_cmnd *srb

if (sendbytes > 8) {
memcpy(buf, inquiry_buf, 8);
- memcpy(buf + 8, inquiry_string, sendbytes - 8);
+ strncpy(buf + 8, inquiry_string, sendbytes - 8);
if (pro_formatter_flag) {
/* Additional Length */
buf[4] = 0x33;