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authorTakashi Iwai <tiwai@suse.de>2022-07-04 14:14:04 +0200
committerTakashi Iwai <tiwai@suse.de>2022-07-04 14:14:04 +0200
commitdd84cfff3cc3b79c9d616f85bd1178df135cbd1a (patch)
treecd02e30a78211bed4f1270877b705a079d4bd364 /mm/util.c
parentALSA: usb-audio: Add quirk for Fiero SC-01 (fw v1.0.0) (diff)
parentASoC: madera: Fix event generation for rate controls (diff)
downloadwireguard-linux-dd84cfff3cc3b79c9d616f85bd1178df135cbd1a.tar.xz
wireguard-linux-dd84cfff3cc3b79c9d616f85bd1178df135cbd1a.zip
Merge tag 'asoc-fix-v5.19-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v5.19 A collection of fixes for v5.19, quite large but nothing major - a good chunk of it is more stuff that was identified by mixer-test regarding event generation.
Diffstat (limited to 'mm/util.c')
-rw-r--r--mm/util.c46
1 files changed, 43 insertions, 3 deletions
diff --git a/mm/util.c b/mm/util.c
index 54e5e761a9a9..0837570c9225 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -27,6 +27,7 @@
#include <linux/uaccess.h>
#include "internal.h"
+#include "swap.h"
/**
* kfree_const - conditionally free memory
@@ -343,8 +344,40 @@ unsigned long randomize_stack_top(unsigned long stack_top)
#endif
}
+/**
+ * randomize_page - Generate a random, page aligned address
+ * @start: The smallest acceptable address the caller will take.
+ * @range: The size of the area, starting at @start, within which the
+ * random address must fall.
+ *
+ * If @start + @range would overflow, @range is capped.
+ *
+ * NOTE: Historical use of randomize_range, which this replaces, presumed that
+ * @start was already page aligned. We now align it regardless.
+ *
+ * Return: A page aligned address within [start, start + range). On error,
+ * @start is returned.
+ */
+unsigned long randomize_page(unsigned long start, unsigned long range)
+{
+ if (!PAGE_ALIGNED(start)) {
+ range -= PAGE_ALIGN(start) - start;
+ start = PAGE_ALIGN(start);
+ }
+
+ if (start > ULONG_MAX - range)
+ range = ULONG_MAX - start;
+
+ range >>= PAGE_SHIFT;
+
+ if (range == 0)
+ return start;
+
+ return start + (get_random_long() % range << PAGE_SHIFT);
+}
+
#ifdef CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
-unsigned long arch_randomize_brk(struct mm_struct *mm)
+unsigned long __weak arch_randomize_brk(struct mm_struct *mm)
{
/* Is the current task 32bit ? */
if (!IS_ENABLED(CONFIG_64BIT) || is_compat_task())
@@ -592,8 +625,15 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
return NULL;
}
- return __vmalloc_node(size, 1, flags, node,
- __builtin_return_address(0));
+ /*
+ * kvmalloc() can always use VM_ALLOW_HUGE_VMAP,
+ * since the callers already cannot assume anything
+ * about the resulting pointer, and cannot play
+ * protection games.
+ */
+ return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
+ flags, PAGE_KERNEL, VM_ALLOW_HUGE_VMAP,
+ node, __builtin_return_address(0));
}
EXPORT_SYMBOL(kvmalloc_node);