From 13cb9d50b1c92b1418d37536be76c3b00d85ab43 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. Signed-off-by: Daniel Cashman Signed-off-by: Daniel Cashman Bug: 27796957 Patchset: ASLR sysctl Change-Id: I5d6283f426337fc82ea7027a71cd13766db0d518 Signed-off-by: Kees Cook --- arch/arm/mm/mmap.c | 2 +- arch/arm64/mm/mmap.c | 4 ++-- arch/mips/mm/mmap.c | 4 ++-- arch/powerpc/kernel/process.c | 4 ++-- arch/powerpc/mm/mmap_64.c | 4 ++-- arch/sparc/kernel/sys_sparc_64.c | 2 +- arch/x86/mm/mmap.c | 6 +++--- 7 files changed, 13 insertions(+), 13 deletions(-) diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index 2761c861300..0a235811b06 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -175,7 +175,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm) if ((current->flags & PF_RANDOMIZE) && !(current->personality & ADDR_NO_RANDOMIZE)) - random_factor = (get_random_int() & ((1 << mmap_rnd_bits) - 1)) << PAGE_SHIFT; + random_factor = (get_random_long() & ((1UL << mmap_rnd_bits) - 1)) << PAGE_SHIFT; if (mmap_is_legacy()) { mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c index 8af07b65eec..83c3df2cb16 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; } diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index 7e5fe2790d8..358820ba62b 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -147,7 +147,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm) unsigned long random_factor = 0UL; if (current->flags & PF_RANDOMIZE) { - random_factor = get_random_int(); + random_factor = get_random_long(); random_factor = random_factor << PAGE_SHIFT; if (TASK_IS_32BIT_ADDR) random_factor &= 0xfffffful; @@ -168,7 +168,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm) static inline unsigned long brk_rnd(void) { - unsigned long rnd = get_random_int(); + unsigned long rnd = get_random_long(); rnd = rnd << PAGE_SHIFT; /* 8MB for 32bit, 256MB for 64bit */ diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index d55357ee902..47936dc128a 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1450,9 +1450,9 @@ static inline unsigned long brk_rnd(void) /* 8MB for 32bit, 1GB for 64bit */ if (is_32bit_task()) - rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT))); + rnd = (get_random_long() % (1UL<<(23-PAGE_SHIFT))); else - rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT))); + rnd = (get_random_long() % (1UL<<(30-PAGE_SHIFT))); return rnd << PAGE_SHIFT; } diff --git a/arch/powerpc/mm/mmap_64.c b/arch/powerpc/mm/mmap_64.c index 67a42ed0d2f..2803d90300a 100644 --- a/arch/powerpc/mm/mmap_64.c +++ b/arch/powerpc/mm/mmap_64.c @@ -60,9 +60,9 @@ static unsigned long mmap_rnd(void) if (current->flags & PF_RANDOMIZE) { /* 8MB for 32bit, 1GB for 64bit */ if (is_32bit_task()) - rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT))); + rnd = get_random_long() % (1<<(23-PAGE_SHIFT)); else - rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT))); + rnd = get_random_long() % (1UL<<(30-PAGE_SHIFT)); } return rnd << PAGE_SHIFT; } diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index be8db9bb787..e08d6124eb6 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -265,7 +265,7 @@ static unsigned long mmap_rnd(void) unsigned long rnd = 0UL; if (current->flags & PF_RANDOMIZE) { - unsigned long val = get_random_int(); + unsigned long val = get_random_long(); if (test_thread_flag(TIF_32BIT)) rnd = (val % (1UL << (23UL-PAGE_SHIFT))); else diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index 8ba10d84ed4..75b36cce24d 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -72,12 +72,12 @@ static unsigned long mmap_rnd(void) if (current->flags & PF_RANDOMIZE) { if (mmap_is_ia32()) #ifdef CONFIG_COMPAT - rnd = (unsigned long)get_random_int() & ((1 << mmap_rnd_compat_bits) - 1); + rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1); #else - rnd = (unsigned long)get_random_int() & ((1 << mmap_rnd_bits) - 1); + rnd = get_random_long() & ((1UL << mmap_rnd_bits) - 1); #endif else - 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