[PATCH 5.2 001/137] cxgb4:Fix out-of-bounds MSI-X info array access

From: Greg Kroah-Hartman
Date: Sun Oct 06 2019 - 13:57:51 EST


From: Vishal Kulkarni <vishal@xxxxxxxxxxx>

[ Upstream commit 6b517374f4ea5a3c6e307e1219ec5f35d42e6d00 ]

When fetching free MSI-X vectors for ULDs, check for the error code
before accessing MSI-X info array. Otherwise, an out-of-bounds access is
attempted, which results in kernel panic.

Fixes: 94cdb8bb993a ("cxgb4: Add support for dynamic allocation of resources for ULD")
Signed-off-by: Shahjada Abul Husain <shahjada@xxxxxxxxxxx>
Signed-off-by: Vishal Kulkarni <vishal@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
@@ -137,13 +137,12 @@ static int uldrx_handler(struct sge_rspq
static int alloc_uld_rxqs(struct adapter *adap,
struct sge_uld_rxq_info *rxq_info, bool lro)
{
- struct sge *s = &adap->sge;
unsigned int nq = rxq_info->nrxq + rxq_info->nciq;
+ int i, err, msi_idx, que_idx = 0, bmap_idx = 0;
struct sge_ofld_rxq *q = rxq_info->uldrxq;
unsigned short *ids = rxq_info->rspq_id;
- unsigned int bmap_idx = 0;
+ struct sge *s = &adap->sge;
unsigned int per_chan;
- int i, err, msi_idx, que_idx = 0;

per_chan = rxq_info->nrxq / adap->params.nports;

@@ -161,6 +160,10 @@ static int alloc_uld_rxqs(struct adapter

if (msi_idx >= 0) {
bmap_idx = get_msix_idx_from_bmap(adap);
+ if (bmap_idx < 0) {
+ err = -ENOSPC;
+ goto freeout;
+ }
msi_idx = adap->msix_info_ulds[bmap_idx].idx;
}
err = t4_sge_alloc_rxq(adap, &q->rspq, false,