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yaml --- r: 23793 b: refs/heads/master c: 913bd90 h: refs/heads/master i: 23791: c4aeae3 v: v3
git-mirror · Mar 25, 2006 · da85df9 · da85df9
1 parent 4a69f84
commit da85df9
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Showing 3 changed files with 14 additions and 5 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: dca99a38bccceda9e079d4c95abefbd9028605fe
+refs/heads/master: 913bd906019514579b3c7ec5ab9c463e89207a57
diff --git a/trunk/fs/binfmt_elf.c b/trunk/fs/binfmt_elf.c
@@ -500,17 +500,22 @@ static unsigned long load_aout_interp(struct exec * interp_ex,
 #define INTERPRETER_AOUT 1
 #define INTERPRETER_ELF 2
 
+#ifndef STACK_RND_MASK
+#define STACK_RND_MASK 0x7ff		/* with 4K pages 8MB of VA */
+#endif
 
 static unsigned long randomize_stack_top(unsigned long stack_top)
 {
 	unsigned int random_variable = 0;
 
-	if (current->flags & PF_RANDOMIZE)
-		random_variable = get_random_int() % (8*1024*1024);
+	if (current->flags & PF_RANDOMIZE) {
+		random_variable = get_random_int() & STACK_RND_MASK;
+		random_variable <<= PAGE_SHIFT;
+	}
 #ifdef CONFIG_STACK_GROWSUP
-	return PAGE_ALIGN(stack_top + random_variable);
+	return PAGE_ALIGN(stack_top) + random_variable;
 #else
-	return PAGE_ALIGN(stack_top - random_variable);
+	return PAGE_ALIGN(stack_top) - random_variable;
 #endif
 }
 

diff --git a/trunk/include/asm-x86_64/elf.h b/trunk/include/asm-x86_64/elf.h
@@ -8,6 +8,7 @@
 #include <asm/ptrace.h>
 #include <asm/user.h>
 #include <asm/processor.h>
+#include <asm/compat.h>
 
 /* x86-64 relocation types */
 #define R_X86_64_NONE		0	/* No reloc */
@@ -157,6 +158,9 @@ extern int dump_task_fpu (struct task_struct *, elf_fpregset_t *);
 #define ELF_CORE_COPY_TASK_REGS(tsk, elf_regs) dump_task_regs(tsk, elf_regs)
 #define ELF_CORE_COPY_FPREGS(tsk, elf_fpregs) dump_task_fpu(tsk, elf_fpregs)
 
+/* 1GB for 64bit, 8MB for 32bit */
+#define STACK_RND_MASK (is_compat_task() ? 0x7ff : 0x3fffff)
+
 #endif
 
 #endif