[RFC PATCH v2 2/2] Architecture defined limit on memory region random shift.

Ilya Smith
2018-03-22T16:36:38Z

Signed-off-by: Ilya Smith <blackzert@gmail.com>
---
arch/alpha/kernel/osf_sys.c | 1 +
arch/arc/mm/mmap.c | 1 +
arch/arm/mm/mmap.c | 2 ++
arch/frv/mm/elf-fdpic.c | 1 +
arch/ia64/kernel/sys_ia64.c | 1 +
arch/ia64/mm/hugetlbpage.c | 1 +
arch/metag/mm/hugetlbpage.c | 1 +
arch/mips/mm/mmap.c | 1 +
arch/parisc/kernel/sys_parisc.c | 2 ++
arch/powerpc/mm/hugetlbpage-radix.c | 1 +
arch/powerpc/mm/mmap.c | 2 ++
arch/powerpc/mm/slice.c | 2 ++
arch/s390/mm/mmap.c | 2 ++
arch/sh/mm/mmap.c | 2 ++
arch/sparc/kernel/sys_sparc_32.c | 1 +
arch/sparc/kernel/sys_sparc_64.c | 2 ++
arch/sparc/mm/hugetlbpage.c | 2 ++
arch/tile/mm/hugetlbpage.c | 2 ++
arch/x86/kernel/sys_x86_64.c | 4 ++++
arch/x86/mm/hugetlbpage.c | 4 ++++
fs/hugetlbfs/inode.c | 1 +
include/linux/mm.h | 1 +
mm/mmap.c | 3 ++-
23 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index fa1a392..0ab9f31 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -1301,6 +1301,7 @@ arch_get_unmapped_area_1(unsigned long addr, unsigned long len,
info.high_limit = limit;
info.align_mask = 0;
info.align_offset = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

diff --git a/arch/arc/mm/mmap.c b/arch/arc/mm/mmap.c
index 2e13683..45225fc 100644
--- a/arch/arc/mm/mmap.c
+++ b/arch/arc/mm/mmap.c
@@ -75,5 +75,6 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.high_limit = TASK_SIZE;
info.align_mask = do_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}
diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index eb1de66..1eb660c 100644
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -101,6 +101,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.high_limit = TASK_SIZE;
info.align_mask = do_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

@@ -152,6 +153,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
info.high_limit = mm->mmap_base;
info.align_mask = do_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

/*
diff --git a/arch/frv/mm/elf-fdpic.c b/arch/frv/mm/elf-fdpic.c
index 46aa289..a2ce2ce 100644
--- a/arch/frv/mm/elf-fdpic.c
+++ b/arch/frv/mm/elf-fdpic.c
@@ -86,6 +86,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
info.high_limit = (current->mm->start_stack - 0x00200000);
info.align_mask = 0;
info.align_offset = 0;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);
if (!(addr & ~PAGE_MASK))
goto success;
diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
index 085adfc..15fa4fb 100644
--- a/arch/ia64/kernel/sys_ia64.c
+++ b/arch/ia64/kernel/sys_ia64.c
@@ -64,6 +64,7 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
info.high_limit = TASK_SIZE;
info.align_mask = align_mask;
info.align_offset = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c
index d16e419..ec7822d 100644
--- a/arch/ia64/mm/hugetlbpage.c
+++ b/arch/ia64/mm/hugetlbpage.c
@@ -162,6 +162,7 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, u
info.high_limit = HPAGE_REGION_BASE + RGN_MAP_LIMIT;
info.align_mask = PAGE_MASK & (HPAGE_SIZE - 1);
info.align_offset = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

diff --git a/arch/metag/mm/hugetlbpage.c b/arch/metag/mm/hugetlbpage.c
index 012ee4c..babd325 100644
--- a/arch/metag/mm/hugetlbpage.c
+++ b/arch/metag/mm/hugetlbpage.c
@@ -191,6 +191,7 @@ hugetlb_get_unmapped_area_new_pmd(unsigned long len)
info.high_limit = TASK_SIZE;
info.align_mask = PAGE_MASK & HUGEPT_MASK;
info.align_offset = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c
index 33d3251..5a3d384 100644
--- a/arch/mips/mm/mmap.c
+++ b/arch/mips/mm/mmap.c
@@ -122,6 +122,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp,
info.flags = 0;
info.low_limit = mm->mmap_base;
info.high_limit = TASK_SIZE;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index 378a754..abf4b05 100644
--- a/arch/parisc/kernel/sys_parisc.c
+++ b/arch/parisc/kernel/sys_parisc.c
@@ -130,6 +130,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.high_limit = mmap_upper_limit();
info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
info.align_offset = shared_align_offset(last_mmap, pgoff);
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

found_addr:
@@ -192,6 +193,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
info.high_limit = mm->mmap_base;
info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
info.align_offset = shared_align_offset(last_mmap, pgoff);
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);
if (!(addr & ~PAGE_MASK))
goto found_addr;
diff --git a/arch/powerpc/mm/hugetlbpage-radix.c b/arch/powerpc/mm/hugetlbpage-radix.c
index 2486bee..1d61a88 100644
--- a/arch/powerpc/mm/hugetlbpage-radix.c
+++ b/arch/powerpc/mm/hugetlbpage-radix.c
@@ -87,6 +87,7 @@ radix__hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = 0;

return vm_unmapped_area(&info);
}
diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c
index d503f34..7fe98c7 100644
--- a/arch/powerpc/mm/mmap.c
+++ b/arch/powerpc/mm/mmap.c
@@ -136,6 +136,7 @@ radix__arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.low_limit = mm->mmap_base;
info.high_limit = high_limit;
info.align_mask = 0;
+ info.random_shift = 0;

return vm_unmapped_area(&info);
}
@@ -180,6 +181,7 @@ radix__arch_get_unmapped_area_topdown(struct file *filp,
info.low_limit = max(PAGE_SIZE, mmap_min_addr);
info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
info.align_mask = 0;
+ info.random_shift = 0;

addr = vm_unmapped_area(&info);
if (!(addr & ~PAGE_MASK))
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 23ec2c5..2005845 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -284,6 +284,7 @@ static unsigned long slice_find_area_bottomup(struct mm_struct *mm,
info.length = len;
info.align_mask = PAGE_MASK & ((1ul << pshift) - 1);
info.align_offset = 0;
+ info.random_shift = 0;

addr = TASK_UNMAPPED_BASE;
/*
@@ -330,6 +331,7 @@ static unsigned long slice_find_area_topdown(struct mm_struct *mm,
info.length = len;
info.align_mask = PAGE_MASK & ((1ul << pshift) - 1);
info.align_offset = 0;
+ info.random_shift = 0;

addr = mm->mmap_base;
/*
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 831bdcf..141823f 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -95,6 +95,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.length = len;
info.low_limit = mm->mmap_base;
info.high_limit = TASK_SIZE;
+ info.random_shift = 0;
if (filp || (flags & MAP_SHARED))
info.align_mask = MMAP_ALIGN_MASK << PAGE_SHIFT;
else
@@ -146,6 +147,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
info.length = len;
info.low_limit = max(PAGE_SIZE, mmap_min_addr);
info.high_limit = mm->mmap_base;
+ info.random_shift = 0;
if (filp || (flags & MAP_SHARED))
info.align_mask = MMAP_ALIGN_MASK << PAGE_SHIFT;
else
diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c
index 6a1a129..d9206c2 100644
--- a/arch/sh/mm/mmap.c
+++ b/arch/sh/mm/mmap.c
@@ -74,6 +74,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.high_limit = TASK_SIZE;
info.align_mask = do_colour_align ? (PAGE_MASK & shm_align_mask) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

@@ -124,6 +125,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
info.high_limit = mm->mmap_base;
info.align_mask = do_colour_align ? (PAGE_MASK & shm_align_mask) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

/*
diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c
index 990703b7..af664ba3 100644
--- a/arch/sparc/kernel/sys_sparc_32.c
+++ b/arch/sparc/kernel/sys_sparc_32.c
@@ -66,6 +66,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
info.align_mask = (flags & MAP_SHARED) ?
(PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index 55416db..3d12e3d 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -131,6 +131,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
info.high_limit = min(task_size, VA_EXCLUDE_START);
info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
@@ -194,6 +195,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
info.high_limit = mm->mmap_base;
info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

/*
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index 0112d69..6d0c032 100644
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -43,6 +43,7 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
info.high_limit = min(task_size, VA_EXCLUDE_START);
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
@@ -75,6 +76,7 @@ hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
info.high_limit = mm->mmap_base;
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

/*
diff --git a/arch/tile/mm/hugetlbpage.c b/arch/tile/mm/hugetlbpage.c
index 0986d42..2b3a9b6 100644
--- a/arch/tile/mm/hugetlbpage.c
+++ b/arch/tile/mm/hugetlbpage.c
@@ -176,6 +176,7 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
info.high_limit = TASK_SIZE;
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}

@@ -193,6 +194,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
info.high_limit = current->mm->mmap_base;
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = 0;
addr = vm_unmapped_area(&info);

/*
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index 676774b..0eda047 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -163,6 +163,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.high_limit = end;
info.align_mask = 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = in_compat_syscall() ?
+ 256 : 0x1000000;
if (filp) {
info.align_mask = get_align_mask();
info.align_offset += get_align_bits();
@@ -224,6 +226,8 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,

info.align_mask = 0;
info.align_offset = pgoff << PAGE_SHIFT;
+ info.random_shift = in_compat_syscall() ?
+ 256 : 0x1000000;
if (filp) {
info.align_mask = get_align_mask();
info.align_offset += get_align_bits();
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 00b2966..f4f6436 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -97,6 +97,8 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,

info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = in_compat_syscall() ?
+ 256 : 0x1000000;
return vm_unmapped_area(&info);
}

@@ -121,6 +123,8 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,

info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = in_compat_syscall() ?
+ 256 : 0x1000000;
addr = vm_unmapped_area(&info);

/*
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 8fe1b0a..83e962e 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -200,6 +200,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
info.high_limit = TASK_SIZE;
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}
#endif
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c716257..f869e6d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2252,6 +2252,7 @@ struct vm_unmapped_area_info {
unsigned long high_limit;
unsigned long align_mask;
unsigned long align_offset;
+ unsigned long random_shift;
};

#ifndef CONFIG_MMU
diff --git a/mm/mmap.c b/mm/mmap.c
index ba9cebb..425fa09 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1938,7 +1938,7 @@ unsigned long unmapped_area_random(struct vm_unmapped_area_info *info)
if (gap_end == gap_start)
return gap_start;
addr = entropy[1] % (min((gap_end - gap_start) >> PAGE_SHIFT,
- 0x10000UL));
+ info->random_shift));
addr = gap_end - (addr << PAGE_SHIFT);
addr += (info->align_offset - addr) & info->align_mask;
return addr;
@@ -2186,6 +2186,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
info.low_limit = mm->mmap_base;
info.high_limit = TASK_SIZE;
info.align_mask = 0;
+ info.random_shift = 0;
return vm_unmapped_area(&info);
}
#endif
--
2.7.4