linux-kernel - [PATCH v3 06/21] x86/kaslr: Drop redundant cur_entry from __process_mem

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Date:   Tue, 28 Jul 2020 18:57:07 -0400
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Kees Cook <keescook@...omium.org>, x86@...nel.org
Cc:     linux-kernel@...r.kernel.org
Subject: [PATCH v3 06/21] x86/kaslr: Drop redundant cur_entry from __process_mem_region

cur_entry is only used as cur_entry.start + cur_entry.size, which is
always equal to end.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
---
 arch/x86/boot/compressed/kaslr.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 848346fc0dbb..f2454eef5790 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -624,7 +624,6 @@ static void __process_mem_region(struct mem_vector *entry,
 {
 	struct mem_vector region, overlap;
 	unsigned long start_orig, end;
-	struct mem_vector cur_entry;
 
 	/* Ignore entries entirely below our minimum. */
 	if (entry->start + entry->size < minimum)
@@ -634,11 +633,9 @@ static void __process_mem_region(struct mem_vector *entry,
 	end = min(entry->size + entry->start, mem_limit);
 	if (entry->start >= end)
 		return;
-	cur_entry.start = entry->start;
-	cur_entry.size = end - entry->start;
 
-	region.start = cur_entry.start;
-	region.size = cur_entry.size;
+	region.start = entry->start;
+	region.size = end - entry->start;
 
 	/* Give up if slot area array is full. */
 	while (slot_area_index < MAX_SLOT_AREA) {
@@ -652,7 +649,7 @@ static void __process_mem_region(struct mem_vector *entry,
 		region.start = ALIGN(region.start, CONFIG_PHYSICAL_ALIGN);
 
 		/* Did we raise the address above the passed in memory entry? */
-		if (region.start > cur_entry.start + cur_entry.size)
+		if (region.start > end)
 			return;
 
 		/* Reduce size by any delta from the original address. */
-- 
2.26.2