ipmi: fix oob access due to uninit smi_msg type

We're hitting OOB accesses in handle_ipmb_direct_rcv_rsp() (memcpy of
size -1) after user space generates a message. Looks like the message
is incorrectly assumed to be of the new IPMB type, because type is never
set and message is allocated with kmalloc() not kzalloc().

Fixes: 059747c245f0 ("ipmi: Add support for IPMB direct messages")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Message-Id: <20211124210323.1950976-1-kuba@kernel.org>
Signed-off-by: Corey Minyard <cminyard@mvista.com>

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index a2ec0171363a6b7505566bf3740d700f9f26d037..7d7df17d8b3d13bb4fee00e46574361111f904df 100644 (file)
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -5033,6 +5033,7 @@ struct ipmi_smi_msg *ipmi_alloc_smi_msg(void)
        if (rv) {
                rv->done = free_smi_msg;
                rv->user_data = NULL;
+               rv->type = IPMI_SMI_MSG_TYPE_NORMAL;
                atomic_inc(&smi_msg_inuse_count);
        }
        return rv;