[PATCH 5.12 266/296] cxgb4: avoid accessing registers when clearing filters

[Greg Kroah-Hartman]

From: Raju Rangoju <rajur@xxxxxxxxxxx>

[ Upstream commit 88c380df84fbd03f9b137c2b9d0a44b9f2f553b0 ]

Hardware register having the server TID base can contain
invalid values when adapter is in bad state (for example,
due to AER fatal error). Reading these invalid values in the
register can lead to out-of-bound memory access. So, fix
by using the saved server TID base when clearing filters.

Fixes: b1a79360ee86 ("cxgb4: Delete all hash and TCAM filters before resource cleanup")
Signed-off-by: Raju Rangoju <rajur@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
index bde8494215c4..e664e05b9f02 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
@@ -1042,7 +1042,7 @@ void clear_all_filters(struct adapter *adapter)
 				cxgb4_del_filter(dev, f->tid, &f->fs);
 		}
 
-		sb = t4_read_reg(adapter, LE_DB_SRVR_START_INDEX_A);
+		sb = adapter->tids.stid_base;
 		for (i = 0; i < sb; i++) {
 			f = (struct filter_entry *)adapter->tids.tid_tab[i];
 
-- 
2.30.2