File libxc-bitmap-longs.patch of Package xen.30823

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File libxc-bitmap-longs.patch of Package xen.30823

From: Olaf Hering <olaf@aepfle.de>
Date: Wed, 9 Dec 2020 16:22:14 +0100
Subject: bitmap longs

tools: allocate bitmaps in units of unsigned long

Allocate enough memory so that the returned pointer can be safely
accessed as an array of unsigned long.

The actual bitmap size in units of bytes, as returned by bitmap_size,
remains unchanged.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 tools/libxc/xc_bitops.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Index: xen-4.14.0-testing/tools/libxc/xc_bitops.h
===================================================================
--- xen-4.14.0-testing.orig/tools/libxc/xc_bitops.h
+++ xen-4.14.0-testing/tools/libxc/xc_bitops.h
@@ -21,7 +21,10 @@ static inline unsigned long bitmap_size(
 
 static inline void *bitmap_alloc(unsigned long nr_bits)
 {
-    return calloc(1, bitmap_size(nr_bits));
+    unsigned long longs;
+
+    longs = (nr_bits + BITS_PER_LONG - 1) / BITS_PER_LONG;
+    return calloc(longs, sizeof(unsigned long));
 }
 
 static inline void bitmap_set(void *addr, unsigned long nr_bits)

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File libxc-bitmap-longs.patch of Package xen.30823

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