[patch 1/2 -next] cxgb4: potential shift wrapping bug
From: Dan Carpenter <hidden>
Date: 2014-10-02 10:20:53
Also in:
kernel-janitors
Subsystem:
cxgb4 ethernet driver (cxgb4), networking drivers, the rest · Maintainers:
Potnuri Bharat Teja, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
"cntxt_id" is an unsigned int but "udb" is a u64 so there is a potential shift wrapping bug here. Signed-off-by: Dan Carpenter <redacted>
diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c
index bb7851e..e8e90ce 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/sge.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c@@ -2258,7 +2258,7 @@ static u64 udb_address(struct adapter *adap, unsigned int cntxt_id, (QUEUESPERPAGEPF1 - QUEUESPERPAGEPF0) * adap->fn); udb_density = 1 << ((qpp >> s_qpp) & QUEUESPERPAGEPF0_MASK); qpshift = PAGE_SHIFT - ilog2(udb_density); - udb = cntxt_id << qpshift; + udb = (u64)cntxt_id << qpshift; udb &= PAGE_MASK; page = udb / PAGE_SIZE; udb += (cntxt_id - (page * udb_density)) * SGE_UDB_SIZE;