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authorHelge Deller <deller@gmx.de>2016-10-16 00:02:27 +0200
committerHelge Deller <deller@gmx.de>2016-12-12 22:21:21 +0100
commit18d98a79382cbe5a7569788d5b7b18e7015506f2 (patch)
treebf5d3b90523528747e7a5d67bc9086c288a94ad5 /arch/parisc
parent69973b830859bc6529a7a0468ba0d80ee5117826 (diff)
parisc: Enable KASLR
Add missing code for userspace executable address randomization, e.g. applications compiled with the gcc -pie option. Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc')
-rw-r--r--arch/parisc/Kconfig1
-rw-r--r--arch/parisc/include/asm/elf.h7
-rw-r--r--arch/parisc/kernel/process.c6
-rw-r--r--arch/parisc/kernel/sys_parisc.c18
4 files changed, 14 insertions, 18 deletions
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index a14b86587013..3a71f38cdc05 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -7,6 +7,7 @@ config PARISC
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_SYSCALL_TRACEPOINTS
select ARCH_WANT_FRAME_POINTERS
+ select ARCH_HAS_ELF_RANDOMIZE
select RTC_CLASS
select RTC_DRV_GENERIC
select INIT_ALL_POSSIBLE
diff --git a/arch/parisc/include/asm/elf.h b/arch/parisc/include/asm/elf.h
index 78c9fd32c554..a6b2a421571e 100644
--- a/arch/parisc/include/asm/elf.h
+++ b/arch/parisc/include/asm/elf.h
@@ -348,9 +348,10 @@ struct pt_regs; /* forward declaration... */
#define ELF_HWCAP 0
-#define STACK_RND_MASK (is_32bit_task() ? \
- 0x7ff >> (PAGE_SHIFT - 12) : \
- 0x3ffff >> (PAGE_SHIFT - 12))
+/* Masks for stack and mmap randomization */
+#define BRK_RND_MASK (is_32bit_task() ? 0x07ffUL : 0x3ffffUL)
+#define MMAP_RND_MASK (is_32bit_task() ? 0x1fffUL : 0x3ffffUL)
+#define STACK_RND_MASK MMAP_RND_MASK
struct mm_struct;
extern unsigned long arch_randomize_brk(struct mm_struct *);
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
index 40639439d8b3..ea6603ee8d24 100644
--- a/arch/parisc/kernel/process.c
+++ b/arch/parisc/kernel/process.c
@@ -276,11 +276,7 @@ void *dereference_function_descriptor(void *ptr)
static inline unsigned long brk_rnd(void)
{
- /* 8MB for 32bit, 1GB for 64bit */
- if (is_32bit_task())
- return (get_random_int() & 0x7ffUL) << PAGE_SHIFT;
- else
- return (get_random_int() & 0x3ffffUL) << PAGE_SHIFT;
+ return (get_random_int() & BRK_RND_MASK) << PAGE_SHIFT;
}
unsigned long arch_randomize_brk(struct mm_struct *mm)
diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index 0a393a04e891..a81e177cac7b 100644
--- a/arch/parisc/kernel/sys_parisc.c
+++ b/arch/parisc/kernel/sys_parisc.c
@@ -225,19 +225,17 @@ static unsigned long mmap_rnd(void)
{
unsigned long rnd = 0;
- /*
- * 8 bits of randomness in 32bit mmaps, 20 address space bits
- * 28 bits of randomness in 64bit mmaps, 40 address space bits
- */
- if (current->flags & PF_RANDOMIZE) {
- if (is_32bit_task())
- rnd = get_random_int() % (1<<8);
- else
- rnd = get_random_int() % (1<<28);
- }
+ if (current->flags & PF_RANDOMIZE)
+ rnd = get_random_int() & MMAP_RND_MASK;
+
return rnd << PAGE_SHIFT;
}
+unsigned long arch_mmap_rnd(void)
+{
+ return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
+}
+
static unsigned long mmap_legacy_base(void)
{
return TASK_UNMAPPED_BASE + mmap_rnd();