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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 23:49:17 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 23:49:17 (GMT)
commit1dcf58d6e6e6eb7ec10e9abc56887b040205b06f (patch)
treec03e7a25ef13eea62f1547914a76e5c68f3f4c28 /arch/powerpc/mm/mmap.c
parent80dcc31fbe55932ac9204daee5f2ebc0c49b6da3 (diff)
parente4b0db72be2487bae0e3251c22f82c104f7c1cfd (diff)
downloadlinux-1dcf58d6e6e6eb7ec10e9abc56887b040205b06f.tar.xz
Merge branch 'akpm' (patches from Andrew)
Merge first patchbomb from Andrew Morton: - arch/sh updates - ocfs2 updates - kernel/watchdog feature - about half of mm/ * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits) Documentation: update arch list in the 'memtest' entry Kconfig: memtest: update number of test patterns up to 17 arm: add support for memtest arm64: add support for memtest memtest: use phys_addr_t for physical addresses mm: move memtest under mm mm, hugetlb: abort __get_user_pages if current has been oom killed mm, mempool: do not allow atomic resizing memcg: print cgroup information when system panics due to panic_on_oom mm: numa: remove migrate_ratelimited mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE mm: split ET_DYN ASLR from mmap ASLR s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE mm: expose arch_mmap_rnd when available s390: standardize mmap_rnd() usage powerpc: standardize mmap_rnd() usage mips: extract logic for mmap_rnd() arm64: standardize mmap_rnd() usage x86: standardize mmap_rnd() usage arm: factor out mmap ASLR into mmap_rnd ...
Diffstat (limited to 'arch/powerpc/mm/mmap.c')
-rw-r--r--arch/powerpc/mm/mmap.c28
1 files changed, 16 insertions, 12 deletions
diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c
index cb8bdbe..0f0502e 100644
--- a/arch/powerpc/mm/mmap.c
+++ b/arch/powerpc/mm/mmap.c
@@ -53,21 +53,20 @@ static inline int mmap_is_legacy(void)
return sysctl_legacy_va_layout;
}
-static unsigned long mmap_rnd(void)
+unsigned long arch_mmap_rnd(void)
{
- unsigned long rnd = 0;
+ unsigned long rnd;
+
+ /* 8MB for 32bit, 1GB for 64bit */
+ if (is_32bit_task())
+ rnd = (unsigned long)get_random_int() % (1<<(23-PAGE_SHIFT));
+ else
+ rnd = (unsigned long)get_random_int() % (1<<(30-PAGE_SHIFT));
- if (current->flags & PF_RANDOMIZE) {
- /* 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;
}
-static inline unsigned long mmap_base(void)
+static inline unsigned long mmap_base(unsigned long rnd)
{
unsigned long gap = rlimit(RLIMIT_STACK);
@@ -76,7 +75,7 @@ static inline unsigned long mmap_base(void)
else if (gap > MAX_GAP)
gap = MAX_GAP;
- return PAGE_ALIGN(TASK_SIZE - gap - mmap_rnd());
+ return PAGE_ALIGN(TASK_SIZE - gap - rnd);
}
/*
@@ -85,6 +84,11 @@ static inline unsigned long mmap_base(void)
*/
void arch_pick_mmap_layout(struct mm_struct *mm)
{
+ unsigned long random_factor = 0UL;
+
+ if (current->flags & PF_RANDOMIZE)
+ random_factor = arch_mmap_rnd();
+
/*
* Fall back to the standard layout if the personality
* bit is set, or if the expected stack growth is unlimited:
@@ -93,7 +97,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
mm->mmap_base = TASK_UNMAPPED_BASE;
mm->get_unmapped_area = arch_get_unmapped_area;
} else {
- mm->mmap_base = mmap_base();
+ mm->mmap_base = mmap_base(random_factor);
mm->get_unmapped_area = arch_get_unmapped_area_topdown;
}
}