Patch set updated for coreboot: broadwell/me: Fix out-of-bounds array access error

[Evan Lojewski]

Evan Lojewski ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/14409

-gerrit

commit 556352b3cfe284cded8b32190f76763a3978110e
Author: Evan Lojewski 
Date:   Mon Apr 18 20:19:03 2016 -0600

broadwell/me: Fix out-of-bounds array access error

Fix an issue where a broadwell machine without the ME
    installed could result in an invalid status code being
    reported. For certain values, this would result in the
    intel_me_status function never returning. Fix has been
    tested on a samus board w and w/o the ME blob installed.

Change-Id: I96667d3b89393f161e4d4efe0544efac98367e6c
    Signed-off-by: Evan Lojewski 
---
 src/soc/intel/broadwell/me_status.c | 50 +++++++++++++++++++++++++++----------
 1 file changed, 37 insertions(+), 13 deletions(-)

diff --git a/src/soc/intel/broadwell/me_status.c b/src/soc/intel/broadwell/me_status.c
index b98be70..819e94c 100644
--- a/src/soc/intel/broadwell/me_status.c
+++ b/src/soc/intel/broadwell/me_status.c
@@ -23,6 +23,12 @@
 #include <soc/me.h>
 #include <delay.h>

+#define ARRAY_TO_ELEMENT(__array__, __index__, __default__) \
+	(((__index__) < ARRAY_SIZE((__array__))) ? \
+		(__array__)[(__index__)] : \
+		(__default__))
+
+
 static inline void me_read_dword_ptr(void *ptr, int offset)
 {
    u32 dword = pci_read_config32(PCH_DEV_ME, offset);
@@ -225,23 +231,37 @@ void intel_me_status(void)
    printk(BIOS_DEBUG, "ME: Update In Progress      : %s\n",
           hfs->update_in_progress ? "YES" : "NO");
    printk(BIOS_DEBUG, "ME: Current Working State   : %s\n",
-	       me_cws_values[hfs->working_state]);
+	       ARRAY_TO_ELEMENT(me_cws_values,
+				hfs->working_state,
+				"Unknown (OOB)"));
    printk(BIOS_DEBUG, "ME: Current Operation State : %s\n",
-	       me_opstate_values[hfs->operation_state]);
+	       ARRAY_TO_ELEMENT(me_opstate_values,
+				hfs->operation_state,
+				"Unknown (OOB)"));
    printk(BIOS_DEBUG, "ME: Current Operation Mode  : %s\n",
-	       me_opmode_values[hfs->operation_mode]);
+	       ARRAY_TO_ELEMENT(me_opmode_values,
+				hfs->operation_mode,
+				"Unknown (OOB)"));
    printk(BIOS_DEBUG, "ME: Error Code              : %s\n",
-	       me_error_values[hfs->error_code]);
+	       ARRAY_TO_ELEMENT(me_error_values,
+				hfs->error_code,
+				"Unknown (OOB)"));
    printk(BIOS_DEBUG, "ME: Progress Phase          : %s\n",
-	       me_progress_values[hfs2->progress_code]);
+	       ARRAY_TO_ELEMENT(me_progress_values,
+				hfs2->progress_code,
+				"Unknown (OOB)"));
    printk(BIOS_DEBUG, "ME: Power Management Event  : %s\n",
-	       me_pmevent_values[hfs2->current_pmevent]);
+	       ARRAY_TO_ELEMENT(me_pmevent_values,
+				hfs2->current_pmevent,
+				"Unknown (OOB)"));

printk(BIOS_DEBUG, "ME: Progress Phase State    : ");
    switch (hfs2->progress_code) {
    case ME_HFS2_PHASE_ROM:		/* ROM Phase */
    	printk(BIOS_DEBUG, "%s",
-		       me_progress_rom_values[hfs2->current_state]);
+		       ARRAY_TO_ELEMENT(me_progress_rom_values,
+					hfs2->current_state,
+					"Unknown (OOB)"));
    	break;

case ME_HFS2_PHASE_UKERNEL:	/* uKernel Phase */
@@ -249,19 +269,23 @@ void intel_me_status(void)
    	break;

case ME_HFS2_PHASE_BUP:		/* Bringup Phase */
-		if (hfs2->current_state < ARRAY_SIZE(me_progress_bup_values)
-		    && me_progress_bup_values[hfs2->current_state])
+		if (ARRAY_TO_ELEMENT(me_progress_bup_values,
+					hfs2->current_state, NULL))
    		printk(BIOS_DEBUG, "%s",
-			       me_progress_bup_values[hfs2->current_state]);
+			       ARRAY_TO_ELEMENT(me_progress_bup_values,
+						hfs2->current_state,
+						NULL));
    	else
    		printk(BIOS_DEBUG, "0x%02x", hfs2->current_state);
    	break;

case ME_HFS2_PHASE_POLICY:	/* Policy Module Phase */
-		if (hfs2->current_state < ARRAY_SIZE(me_progress_policy_values)
-		    && me_progress_policy_values[hfs2->current_state])
+		if (ARRAY_TO_ELEMENT(me_progress_policy_values,
+					hfs2->current_state, NULL))
    		printk(BIOS_DEBUG, "%s",
-			       me_progress_policy_values[hfs2->current_state]);
+			       ARRAY_TO_ELEMENT(me_progress_policy_values,
+						hfs2->current_state,
+						NULL));
    	else
    		printk(BIOS_DEBUG, "0x%02x", hfs2->current_state);
    	break;