[media] firewire: firedtv-avc: fix more potential buffer overflow
"program_info_length" is user controlled and can go up to 4095. The
operand[] array has 509 bytes so we need to add a limit here to prevent
buffer overflows.
The " - 4" in the limit check is because we have 4 bytes more data to
add after the memcpy().
[mchehab@osg.samsung.com: as I merged the version 1 of the patch, I needed
to rebase to apply just the differences between v1 and v2]
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/firewire/firedtv-avc.c b/drivers/media/firewire/firedtv-avc.c
index ac17567..251a556 100644
--- a/drivers/media/firewire/firedtv-avc.c
+++ b/drivers/media/firewire/firedtv-avc.c
@@ -1157,7 +1157,7 @@
if (pmt_cmd_id != 1 && pmt_cmd_id != 4)
dev_err(fdtv->device,
"invalid pmt_cmd_id %d\n", pmt_cmd_id);
- if (program_info_length > sizeof(c->operand) - write_pos) {
+ if (program_info_length > sizeof(c->operand) - 4 - write_pos) {
ret = -EINVAL;
goto out;
}
@@ -1184,7 +1184,8 @@
dev_err(fdtv->device, "invalid pmt_cmd_id %d "
"at stream level\n", pmt_cmd_id);
- if (es_info_length > sizeof(c->operand) - write_pos) {
+ if (es_info_length > sizeof(c->operand) - 4 -
+ write_pos) {
ret = -EINVAL;
goto out;
}