From ffabe4b59ef414b92894cf5b40e4e1e59eaac011 Mon Sep 17 00:00:00 2001 From: dcashman Date: Wed, 24 Feb 2016 13:31:22 -0800 Subject: BACKPORT: FROMLIST: mm: ASLR: use get_random_long() (cherry picked from commit https://lkml.org/lkml/2016/2/4/833) Replace calls to get_random_int() followed by a cast to (unsigned long) with calls to get_random_long(). Also address shifting bug which, in case of x86 removed entropy mask for mmap_rnd_bits values > 31 bits. Bug: 26963541 Signed-off-by: Daniel Cashman Signed-off-by: Daniel Cashman Change-Id: Ie577b21a0678cf4b21eae06bddd8ccb27cbe70ff --- arch/arm64/mm/mmap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c index 8af07b65e..8f6bcc3f4 100644 --- a/arch/arm64/mm/mmap.c +++ b/arch/arm64/mm/mmap.c @@ -54,10 +54,10 @@ static unsigned long mmap_rnd(void) if (current->flags & PF_RANDOMIZE) { #ifdef CONFIG_COMPAT if (test_thread_flag(TIF_32BIT)) - rnd = (unsigned long)get_random_int() & ((1 << mmap_rnd_compat_bits) - 1); + rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1); else #endif - rnd = (unsigned long)get_random_int() & ((1 << mmap_rnd_bits) - 1); + rnd = get_random_long() & ((1UL << mmap_rnd_bits) - 1); } return rnd << PAGE_SHIFT; } -- cgit v1.2.3