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FAILED: patch "[PATCH] powerpc/eeh: Null check uses of eeh_pe_bus_get" failed to apply to 4.4-stable tree

PATCH [email protected] 1 participant 1 message Oct 26, 2016

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Stable branch PowerPC PCI enhanced error handling (eeh) for PowerPC
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The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

Quoted 1 line

From 04fec21c06e35b169a83e75a84a015ab4606bf5e Mon Sep 17 00:00:00 2001

From: Russell Currey <[email protected]>
Date: Mon, 12 Sep 2016 14:17:22 +1000
Subject: [PATCH] powerpc/eeh: Null check uses of eeh_pe_bus_get

eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE. Some callers don't check this, and can cause a null pointer dereference under certain circumstances.

Fix this by checking NULL everywhere eeh_pe_bus_get() is called.

Fixes 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event")
Cc [email protected] # v3.11+
Signed-off-by Russell Currey <[email protected]>
Reviewed-by Andrew Donnellan <[email protected]>
Signed-off-by Michael Ellerman <[email protected]>
arch/powerpc/kernel/eeh_driver.c +8 -0
index 5f36e8a70daa..29aa8d1ce273 100644
@@ -994,6 +994,14 @@ static void eeh_handle_special_event(void)
 				/* Notify all devices to be down */
 				eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
 				bus = eeh_pe_bus_get(phb_pe);
+				if (!bus) {
+					pr_err("%s: Cannot find PCI bus for "
+					       "PHB#%d-PE#%x\n",
+					       __func__,
+					       pe->phb->global_number,
+					       pe->addr);
+					break;
+				}
 				eeh_pe_dev_traverse(pe,
 					eeh_report_failure, NULL);
 				pci_hp_remove_devices(bus);
arch/powerpc/platforms/powernv/eeh-powernv.c +5 -0
index 86544ea85dc3..cb08e6aaf9bd 100644
@@ -1091,6 +1091,11 @@ static int pnv_eeh_reset(struct eeh_pe *pe, int option)
 	}
 
 	bus = eeh_pe_bus_get(pe);
+	if (!bus) {
+		pr_err("%s: Cannot find PCI bus for PHB#%d-PE#%x\n",
+			__func__, pe->phb->global_number, pe->addr);
+		return -EIO;
+	}
 	if (pe->type & EEH_PE_VF)
 		return pnv_eeh_reset_vf_pe(pe, option);