[PATCH 11/17] libfcoe: Handle duplicate critical descriptors

Robert Love
2010-06-11T23:44:26Z

From: Bhanu Prakash Gollapudi <bprakash@broadcom.com>

As per FC-BB-5 rev 2, section 7.8.6.2, malformed FIP frame shall be
discarded. Drop discovery adv, ELS and CLV's with duplicate critical
descriptors.

[Resending after incorporating Joe's review comments]

Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
---
drivers/scsi/fcoe/libfcoe.c | 41 +++++++++++++++++++++++++++++++++++++++++
1 files changed, 41 insertions(+), 0 deletions(-)

diff --git a/drivers/scsi/fcoe/libfcoe.c b/drivers/scsi/fcoe/libfcoe.c
index 27c21ca..db7185c 100644
--- a/drivers/scsi/fcoe/libfcoe.c
+++ b/drivers/scsi/fcoe/libfcoe.c
@@ -640,6 +640,7 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
unsigned long t;
size_t rlen;
size_t dlen;
+ u32 desc_mask;

memset(fcf, 0, sizeof(*fcf));
fcf->fka_period = msecs_to_jiffies(FCOE_CTLR_DEF_FKA);
@@ -647,6 +648,12 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
fiph = (struct fip_header *)skb->data;
fcf->flags = ntohs(fiph->fip_flags);

+ /*
+ * mask of required descriptors. validating each one clears its bit.
+ */
+ desc_mask = BIT(FIP_DT_PRI) | BIT(FIP_DT_MAC) | BIT(FIP_DT_NAME) |
+ BIT(FIP_DT_FAB) | BIT(FIP_DT_FKA);
+
rlen = ntohs(fiph->fip_dl_len) * 4;
if (rlen + sizeof(*fiph) > skb->len)
return -EINVAL;
@@ -656,11 +663,19 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
dlen = desc->fip_dlen * FIP_BPW;
if (dlen < sizeof(*desc) || dlen > rlen)
return -EINVAL;
+ /* Drop Adv if there are duplicate critical descriptors */
+ if ((desc->fip_dtype < 32) &&
+ !(desc_mask & 1U << desc->fip_dtype)) {
+ LIBFCOE_FIP_DBG(fip, "Duplicate Critical "
+ "Descriptors in FIP adv\n");
+ return -EINVAL;
+ }
switch (desc->fip_dtype) {
case FIP_DT_PRI:
if (dlen != sizeof(struct fip_pri_desc))
goto len_err;
fcf->pri = ((struct fip_pri_desc *)desc)->fd_pri;
+ desc_mask &= ~BIT(FIP_DT_PRI);
break;
case FIP_DT_MAC:
if (dlen != sizeof(struct fip_mac_desc))
@@ -673,12 +688,14 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
"in FIP adv\n");
return -EINVAL;
}
+ desc_mask &= ~BIT(FIP_DT_MAC);
break;
case FIP_DT_NAME:
if (dlen != sizeof(struct fip_wwn_desc))
goto len_err;
wwn = (struct fip_wwn_desc *)desc;
fcf->switch_name = get_unaligned_be64(&wwn->fd_wwn);
+ desc_mask &= ~BIT(FIP_DT_NAME);
break;
case FIP_DT_FAB:
if (dlen != sizeof(struct fip_fab_desc))
@@ -687,6 +704,7 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
fcf->fabric_name = get_unaligned_be64(&fab->fd_wwn);
fcf->vfid = ntohs(fab->fd_vfid);
fcf->fc_map = ntoh24(fab->fd_map);
+ desc_mask &= ~BIT(FIP_DT_FAB);
break;
case FIP_DT_FKA:
if (dlen != sizeof(struct fip_fka_desc))
@@ -697,6 +715,7 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
t = ntohl(fka->fd_fka_period);
if (t >= FCOE_CTLR_MIN_FKA)
fcf->fka_period = msecs_to_jiffies(t);
+ desc_mask &= ~BIT(FIP_DT_FKA);
break;
case FIP_DT_MAP_OUI:
case FIP_DT_FCOE_SIZE:
@@ -719,6 +738,11 @@ static int fcoe_ctlr_parse_adv(struct fcoe_ctlr *fip,
return -EINVAL;
if (!fcf->switch_name || !fcf->fabric_name)
return -EINVAL;
+ if (desc_mask) {
+ LIBFCOE_FIP_DBG(fip, "adv missing descriptors mask %x\n",
+ desc_mask);
+ return -EINVAL;
+ }
return 0;

len_err:
@@ -847,6 +871,7 @@ static void fcoe_ctlr_recv_els(struct fcoe_ctlr *fip, struct sk_buff *skb)
size_t els_len = 0;
size_t rlen;
size_t dlen;
+ u32 dupl_desc = 0;

fiph = (struct fip_header *)skb->data;
sub = fiph->fip_subcode;
@@ -862,6 +887,15 @@ static void fcoe_ctlr_recv_els(struct fcoe_ctlr *fip, struct sk_buff *skb)
dlen = desc->fip_dlen * FIP_BPW;
if (dlen < sizeof(*desc) || dlen > rlen)
goto drop;
+ /* Drop ELS if there are duplicate critical descriptors */
+ if (desc->fip_dtype < 32) {
+ if (dupl_desc & 1U << desc->fip_dtype) {
+ LIBFCOE_FIP_DBG(fip, "Duplicate Critical "
+ "Descriptors in FIP ELS\n");
+ goto drop;
+ }
+ dupl_desc |= (1 << desc->fip_dtype);
+ }
switch (desc->fip_dtype) {
case FIP_DT_MAC:
if (dlen != sizeof(struct fip_mac_desc))
@@ -973,6 +1007,13 @@ static void fcoe_ctlr_recv_clr_vlink(struct fcoe_ctlr *fip,
dlen = desc->fip_dlen * FIP_BPW;
if (dlen > rlen)
return;
+ /* Drop CVL if there are duplicate critical descriptors */
+ if ((desc->fip_dtype < 32) &&
+ !(desc_mask & 1U << desc->fip_dtype)) {
+ LIBFCOE_FIP_DBG(fip, "Duplicate Critical "
+ "Descriptors in FIP CVL\n");
+ return;
+ }
switch (desc->fip_dtype) {
case FIP_DT_MAC:
mp = (struct fip_mac_desc *)desc;