Bluetooth: Fix false-positive "uninitialized" compiler warning

Some gcc versions don't seem to be able to properly track the flow of
the smp_cmd_pairing_random() function and end up causing the following
types of (false-positive) warnings:

 smp.c:1995:6: warning: ‘nb’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
 smp.c:1995:6: warning: ‘na’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
       ^
 smp.c:1995:6: warning: ‘pkbx’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
       ^
 smp.c:1995:6: warning: ‘pkax’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);

This patch fixes the issue by moving the pkax/pkbx and na/nb
initialization earlier in the function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Johan Hedberg 2014-12-03 16:26:37 +02:00 committed by Marcel Holtmann
parent 7f376cd6dc
commit 580039e838

View file

@ -1947,6 +1947,18 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
if (!test_bit(SMP_FLAG_SC, &smp->flags))
return smp_random(smp);
if (hcon->out) {
pkax = smp->local_pk;
pkbx = smp->remote_pk;
na = smp->prnd;
nb = smp->rrnd;
} else {
pkax = smp->remote_pk;
pkbx = smp->local_pk;
na = smp->rrnd;
nb = smp->prnd;
}
if (smp->method == REQ_OOB) {
if (!hcon->out)
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
@ -1969,20 +1981,10 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
if (memcmp(smp->pcnf, cfm, 16))
return SMP_CONFIRM_FAILED;
pkax = smp->local_pk;
pkbx = smp->remote_pk;
na = smp->prnd;
nb = smp->rrnd;
} else {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
smp->prnd);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
pkax = smp->remote_pk;
pkbx = smp->local_pk;
na = smp->rrnd;
nb = smp->prnd;
}
mackey_and_ltk: