---

yaml --- r: 138494 b: refs/heads/master c: 912f9ee h: refs/heads/master v: v3
git-mirror · Feb 23, 2009 · a1a0e01 · a1a0e01
1 parent 02313e7
commit a1a0e01
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Showing 3 changed files with 27 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d839088caec6891a5070f0b1ce61031e458533a9
+refs/heads/master: 912f9ee21c836081e3c96dfe61025841ebeb95da
diff --git a/trunk/arch/powerpc/include/asm/elf.h b/trunk/arch/powerpc/include/asm/elf.h
@@ -276,6 +276,9 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
 	(0x7ff >> (PAGE_SHIFT - 12)) : \
 	(0x3ffff >> (PAGE_SHIFT - 12)))
 
+extern unsigned long arch_randomize_brk(struct mm_struct *mm);
+#define arch_randomize_brk arch_randomize_brk
+
 #endif /* __KERNEL__ */
 
 /*

diff --git a/trunk/arch/powerpc/kernel/process.c b/trunk/arch/powerpc/kernel/process.c
@@ -1147,3 +1147,26 @@ unsigned long arch_align_stack(unsigned long sp)
 		sp -= get_random_int() & ~PAGE_MASK;
 	return sp & ~0xf;
 }
+
+static inline unsigned long brk_rnd(void)
+{
+        unsigned long rnd = 0;
+
+	/* 8MB for 32bit, 1GB for 64bit */
+	if (is_32bit_task())
+		rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT)));
+	else
+		rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT)));
+
+	return rnd << PAGE_SHIFT;
+}
+
+unsigned long arch_randomize_brk(struct mm_struct *mm)
+{
+	unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
+
+	if (ret < mm->brk)
+		return mm->brk;
+
+	return ret;
+}