[PATCH 5.10 100/142] iwlwifi: pcie: avoid potential PNVM leaks

[Greg Kroah-Hartman]

From: Johannes Berg <johannes.berg@xxxxxxxxx>

[ Upstream commit 34b9434cd0d425330a0467e767f8d047ef62964d ]

If we erroneously try to set the PNVM data again after it has
already been set, we could leak the old DMA memory. Avoid that
and warn, we shouldn't be doing this.

Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Fixes: 6972592850c0 ("iwlwifi: read and parse PNVM file")
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/iwlwifi.20210115130252.929c2d680429.I086b9490e6c005f3bcaa881b617e9f61908160f3@changeid
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
index 5512e3c630c31..eeb87cf5ee857 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
@@ -341,6 +341,9 @@ int iwl_trans_pcie_ctx_info_gen3_set_pnvm(struct iwl_trans *trans,
 		return ret;
 	}
 
+	if (WARN_ON(prph_sc_ctrl->pnvm_cfg.pnvm_size))
+		return -EBUSY;
+
 	prph_sc_ctrl->pnvm_cfg.pnvm_base_addr =
 		cpu_to_le64(trans_pcie->pnvm_dram.physical);
 	prph_sc_ctrl->pnvm_cfg.pnvm_size =
-- 
2.27.0