From: Kees Cook keescook@chromium.org
[ Upstream commit 0668716506ca66f90d395f36ccdaebc3e0e84801 ]
Avoid potential use-after-free condition under memory pressure. If the kzalloc() fails, q_vector will be freed but left in the original adapter->q_vector[v_idx] array position.
Cc: Jesse Brandeburg jesse.brandeburg@intel.com Cc: Tony Nguyen anthony.l.nguyen@intel.com Cc: "David S. Miller" davem@davemloft.net Cc: Eric Dumazet edumazet@google.com Cc: Jakub Kicinski kuba@kernel.org Cc: Paolo Abeni pabeni@redhat.com Cc: intel-wired-lan@lists.osuosl.org Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook keescook@chromium.org Reviewed-by: Michael J. Ruhl michael.j.ruhl@intel.com Reviewed-by: Jacob Keller jacob.e.keller@intel.com Tested-by: Gurucharan gurucharanx.g@intel.com (A Contingent worker at Intel) Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igb/igb_main.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 473158c09f1d..24a6ae19ad8e 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -1202,8 +1202,12 @@ static int igb_alloc_q_vector(struct igb_adapter *adapter, if (!q_vector) { q_vector = kzalloc(size, GFP_KERNEL); } else if (size > ksize(q_vector)) { - kfree_rcu(q_vector, rcu); - q_vector = kzalloc(size, GFP_KERNEL); + struct igb_q_vector *new_q_vector; + + new_q_vector = kzalloc(size, GFP_KERNEL); + if (new_q_vector) + kfree_rcu(q_vector, rcu); + q_vector = new_q_vector; } else { memset(q_vector, 0, size); }