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author | Hugh Dickins <hughd@google.com> | 2017-06-19 20:32:47 +0200 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2017-07-02 17:12:47 +0100 |
commit | 640c7dfdc7c723143b1ce42f5569ec8565cbbde7 (patch) | |
tree | af206a581973d0a7521dad75faecbe9f20d48818 /arch | |
parent | 641fbf5980efa6a6a2d820344eb03959e29afb6f (diff) | |
download | linux-stable-640c7dfdc7c723143b1ce42f5569ec8565cbbde7.tar.gz linux-stable-640c7dfdc7c723143b1ce42f5569ec8565cbbde7.tar.bz2 linux-stable-640c7dfdc7c723143b1ce42f5569ec8565cbbde7.zip |
mm: larger stack guard gap, between vmas
commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream.
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.
This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.
Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.
One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications. For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).
Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.
Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Hugh Dickins: Backported to 3.2]
[bwh: Fix more instances of vma->vm_start in sparc64 impl. of
arch_get_unmapped_area_topdown() and generic impl. of
hugetlb_get_unmapped_area()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/alpha/kernel/osf_sys.c | 2 | ||||
-rw-r--r-- | arch/arm/mm/mmap.c | 12 | ||||
-rw-r--r-- | arch/frv/mm/elf-fdpic.c | 6 | ||||
-rw-r--r-- | arch/ia64/kernel/sys_ia64.c | 18 | ||||
-rw-r--r-- | arch/ia64/mm/hugetlbpage.c | 4 | ||||
-rw-r--r-- | arch/mips/mm/mmap.c | 19 | ||||
-rw-r--r-- | arch/parisc/kernel/sys_parisc.c | 40 | ||||
-rw-r--r-- | arch/powerpc/mm/slice.c | 24 | ||||
-rw-r--r-- | arch/sh/mm/mmap.c | 29 | ||||
-rw-r--r-- | arch/sparc/kernel/sys_sparc_32.c | 2 | ||||
-rw-r--r-- | arch/sparc/kernel/sys_sparc_64.c | 30 | ||||
-rw-r--r-- | arch/sparc/mm/hugetlbpage.c | 27 | ||||
-rw-r--r-- | arch/tile/mm/hugetlbpage.c | 26 | ||||
-rw-r--r-- | arch/x86/kernel/sys_x86_64.c | 29 | ||||
-rw-r--r-- | arch/x86/mm/hugetlbpage.c | 24 |
15 files changed, 179 insertions, 113 deletions
diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 01e8715e26d9..b9abe5bb437b 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -1147,7 +1147,7 @@ arch_get_unmapped_area_1(unsigned long addr, unsigned long len, /* At this point: (!vma || addr < vma->vm_end). */ if (limit - len < addr) return -ENOMEM; - if (!vma || addr + len <= vma->vm_start) + if (!vma || addr + len <= vm_start_gap(vma)) return addr; addr = vma->vm_end; vma = vma->vm_next; diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index 44b628e4d6ea..4497b5ef688e 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -30,7 +30,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - unsigned long start_addr; + unsigned long start_addr, vm_start; int do_align = 0; int aliasing = cache_is_vipt_aliasing(); @@ -62,7 +62,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } if (len > mm->cached_hole_size) { @@ -96,15 +96,17 @@ full_search: } return -ENOMEM; } - if (!vma || addr + len <= vma->vm_start) { + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || addr + len <= vm_start) { /* * Remember the place where we stopped the search: */ mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = vma->vm_end; if (do_align) addr = COLOUR_ALIGN(addr, pgoff); diff --git a/arch/frv/mm/elf-fdpic.c b/arch/frv/mm/elf-fdpic.c index 385fd30b142f..96eca58b9679 100644 --- a/arch/frv/mm/elf-fdpic.c +++ b/arch/frv/mm/elf-fdpic.c @@ -74,7 +74,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi addr = PAGE_ALIGN(addr); vma = find_vma(current->mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) goto success; } @@ -89,7 +89,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi for (; vma; vma = vma->vm_next) { if (addr > limit) break; - if (addr + len <= vma->vm_start) + if (addr + len <= vm_start_gap(vma)) goto success; addr = vma->vm_end; } @@ -104,7 +104,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi for (; vma; vma = vma->vm_next) { if (addr > limit) break; - if (addr + len <= vma->vm_start) + if (addr + len <= vm_start_gap(vma)) goto success; addr = vma->vm_end; } diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c index 609d50056a6c..77c0aff5aaf0 100644 --- a/arch/ia64/kernel/sys_ia64.c +++ b/arch/ia64/kernel/sys_ia64.c @@ -27,7 +27,8 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len long map_shared = (flags & MAP_SHARED); unsigned long start_addr, align_mask = PAGE_SIZE - 1; struct mm_struct *mm = current->mm; - struct vm_area_struct *vma; + struct vm_area_struct *vma, *prev; + unsigned long prev_end; if (len > RGN_MAP_LIMIT) return -ENOMEM; @@ -58,7 +59,17 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len full_search: start_addr = addr = (addr + align_mask) & ~align_mask; - for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { + for (vma = find_vma_prev(mm, addr, &prev); ; prev = vma, + vma = vma->vm_next) { + if (prev) { + prev_end = vm_end_gap(prev); + if (addr < prev_end) { + addr = (prev_end + align_mask) & ~align_mask; + /* If vma already violates gap, forget it */ + if (vma && addr > vma->vm_start) + addr = vma->vm_start; + } + } /* At this point: (!vma || addr < vma->vm_end). */ if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) { if (start_addr != TASK_UNMAPPED_BASE) { @@ -68,12 +79,11 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len } return -ENOMEM; } - if (!vma || addr + len <= vma->vm_start) { + if (!vma || addr + len <= vm_start_gap(vma)) { /* Remember the address where we stopped this search: */ mm->free_area_cache = addr + len; return addr; } - addr = (vma->vm_end + align_mask) & ~align_mask; } } diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c index 5ca674b74737..66a1ec0a2467 100644 --- a/arch/ia64/mm/hugetlbpage.c +++ b/arch/ia64/mm/hugetlbpage.c @@ -171,9 +171,9 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, u /* At this point: (!vmm || addr < vmm->vm_end). */ if (REGION_OFFSET(addr) + len > RGN_MAP_LIMIT) return -ENOMEM; - if (!vmm || (addr + len) <= vmm->vm_start) + if (!vmm || (addr + len) <= vm_start_gap(vmm)) return addr; - addr = ALIGN(vmm->vm_end, HPAGE_SIZE); + addr = ALIGN(vm_end_gap(vmm), HPAGE_SIZE); } } diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index 302d779d5b0d..a79ddcfec1c7 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -70,6 +70,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, struct mm_struct *mm = current->mm; struct vm_area_struct *vma; unsigned long addr = addr0; + unsigned long vm_start; int do_color_align; if (unlikely(len > TASK_SIZE)) @@ -103,7 +104,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -118,7 +119,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, /* At this point: (!vma || addr < vma->vm_end). */ if (TASK_SIZE - len < addr) return -ENOMEM; - if (!vma || addr + len <= vma->vm_start) + if (!vma || addr + len <= vm_start_gap(vma)) return addr; addr = vma->vm_end; if (do_color_align) @@ -145,7 +146,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, /* make sure it can fit in the remaining address space */ if (likely(addr > len)) { vma = find_vma(mm, addr - len); - if (!vma || addr <= vma->vm_start) { + if (!vma || addr <= vm_start_gap(vma)) { /* cache the address as a hint for next time */ return mm->free_area_cache = addr - len; } @@ -165,20 +166,22 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, * return with success: */ vma = find_vma(mm, addr); - if (likely(!vma || addr + len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* cache the address as a hint for next time */ return mm->free_area_cache = addr; } /* remember the largest hole we saw so far */ - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; /* try just below the current vma->vm_start */ - addr = vma->vm_start - len; + addr = vm_start - len; if (do_color_align) addr = COLOUR_ALIGN_DOWN(addr, pgoff); - } while (likely(len < vma->vm_start)); + } while (likely(len < vm_start)); bottomup: /* diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c index 7ea75d14aa65..1d4ac8d7cdd4 100644 --- a/arch/parisc/kernel/sys_parisc.c +++ b/arch/parisc/kernel/sys_parisc.c @@ -35,17 +35,27 @@ static unsigned long get_unshared_area(unsigned long addr, unsigned long len) { - struct vm_area_struct *vma; + struct vm_area_struct *vma, *prev; + unsigned long prev_end; addr = PAGE_ALIGN(addr); - for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) { + for (vma = find_vma_prev(current->mm, addr, &prev); ; prev = vma, + vma = vma->vm_next) { + if (prev) { + prev_end = vm_end_gap(prev); + if (addr < prev_end) { + addr = prev_end; + /* If vma already violates gap, forget it */ + if (vma && addr > vma->vm_start) + addr = vma->vm_start; + } + } /* At this point: (!vma || addr < vma->vm_end). */ if (TASK_SIZE - len < addr) return -ENOMEM; - if (!vma || addr + len <= vma->vm_start) + if (!vma || addr + len <= vm_start_gap(vma)) return addr; - addr = vma->vm_end; } } @@ -70,22 +80,32 @@ static int get_offset(struct address_space *mapping) static unsigned long get_shared_area(struct address_space *mapping, unsigned long addr, unsigned long len, unsigned long pgoff) { - struct vm_area_struct *vma; + struct vm_area_struct *vma, *prev; + unsigned long prev_end; int offset = mapping ? get_offset(mapping) : 0; offset = (offset + (pgoff << PAGE_SHIFT)) & 0x3FF000; addr = DCACHE_ALIGN(addr - offset) + offset; - for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) { + for (vma = find_vma_prev(current->mm, addr, &prev); ; prev = vma, + vma = vma->vm_next) { + if (prev) { + prev_end = vm_end_gap(prev); + if (addr < prev_end) { + addr = DCACHE_ALIGN(prev_end - offset) + offset; + if (addr < prev_end) /* handle wraparound */ + return -ENOMEM; + /* If vma already violates gap, forget it */ + if (vma && addr > vma->vm_start) + addr = vma->vm_start; + } + } /* At this point: (!vma || addr < vma->vm_end). */ if (TASK_SIZE - len < addr) return -ENOMEM; - if (!vma || addr + len <= vma->vm_start) + if (!vma || addr + len <= vm_start_gap(vma)) return addr; - addr = DCACHE_ALIGN(vma->vm_end - offset) + offset; - if (addr < vma->vm_end) /* handle wraparound */ - return -ENOMEM; } } diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index 73709f7ce92c..57654c9b70f8 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -98,7 +98,7 @@ static int slice_area_is_free(struct mm_struct *mm, unsigned long addr, if ((mm->task_size - len) < addr) return 0; vma = find_vma(mm, addr); - return (!vma || (addr + len) <= vma->vm_start); + return (!vma || (addr + len) <= vm_start_gap(vma)); } static int slice_low_has_vma(struct mm_struct *mm, unsigned long slice) @@ -227,7 +227,7 @@ static unsigned long slice_find_area_bottomup(struct mm_struct *mm, int psize, int use_cache) { struct vm_area_struct *vma; - unsigned long start_addr, addr; + unsigned long start_addr, addr, vm_start; struct slice_mask mask; int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT); @@ -256,7 +256,9 @@ full_search: addr = _ALIGN_UP(addr + 1, 1ul << SLICE_HIGH_SHIFT); continue; } - if (!vma || addr + len <= vma->vm_start) { + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || addr + len <= vm_start) { /* * Remember the place where we stopped the search: */ @@ -264,8 +266,8 @@ full_search: mm->free_area_cache = addr + len; return addr; } - if (use_cache && (addr + mm->cached_hole_size) < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (use_cache && (addr + mm->cached_hole_size) < vm_start) + mm->cached_hole_size = vm_start - addr; addr = vma->vm_end; } @@ -284,7 +286,7 @@ static unsigned long slice_find_area_topdown(struct mm_struct *mm, int psize, int use_cache) { struct vm_area_struct *vma; - unsigned long addr; + unsigned long addr, vm_start; struct slice_mask mask; int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT); @@ -336,7 +338,9 @@ static unsigned long slice_find_area_topdown(struct mm_struct *mm, * return with success: */ vma = find_vma(mm, addr); - if (!vma || (addr + len) <= vma->vm_start) { + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || (addr + len) <= vm_start) { /* remember the address as a hint for next time */ if (use_cache) mm->free_area_cache = addr; @@ -344,11 +348,11 @@ static unsigned long slice_find_area_topdown(struct mm_struct *mm, } /* remember the largest hole we saw so far */ - if (use_cache && (addr + mm->cached_hole_size) < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (use_cache && (addr + mm->cached_hole_size) < vm_start) + mm->cached_hole_size = vm_start - addr; /* try just below the current vma->vm_start */ - addr = vma->vm_start; + addr = vm_start; } /* diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c index afeb710ec5c3..22eff46d8ef5 100644 --- a/arch/sh/mm/mmap.c +++ b/arch/sh/mm/mmap.c @@ -47,7 +47,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - unsigned long start_addr; + unsigned long start_addr, vm_start; int do_colour_align; if (flags & MAP_FIXED) { @@ -75,7 +75,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -106,15 +106,17 @@ full_search: } return -ENOMEM; } - if (likely(!vma || addr + len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* * Remember the place where we stopped the search: */ mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = vma->vm_end; if (do_colour_align) @@ -130,6 +132,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, struct vm_area_struct *vma; struct mm_struct *mm = current->mm; unsigned long addr = addr0; + unsigned long vm_start; int do_colour_align; if (flags & MAP_FIXED) { @@ -158,7 +161,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -179,7 +182,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, /* make sure it can fit in the remaining address space */ if (likely(addr > len)) { vma = find_vma(mm, addr-len); - if (!vma || addr <= vma->vm_start) { + if (!vma || addr <= vm_start_gap(vma)) { /* remember the address as a hint for next time */ return (mm->free_area_cache = addr-len); } @@ -199,20 +202,22 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, * return with success: */ vma = find_vma(mm, addr); - if (likely(!vma || addr+len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* remember the address as a hint for next time */ return (mm->free_area_cache = addr); } /* remember the largest hole we saw so far */ - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; /* try just below the current vma->vm_start */ - addr = vma->vm_start-len; + addr = vm_start-len; if (do_colour_align) addr = COLOUR_ALIGN_DOWN(addr, pgoff); - } while (likely(len < vma->vm_start)); + } while (likely(len < vm_start)); bottomup: /* diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c index 42b282fa6112..eeae89bada55 100644 --- a/arch/sparc/kernel/sys_sparc_32.c +++ b/arch/sparc/kernel/sys_sparc_32.c @@ -71,7 +71,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi } if (TASK_SIZE - PAGE_SIZE - len < addr) return -ENOMEM; - if (!vmm || addr + len <= vmm->vm_start) + if (!vmm || addr + len <= vm_start_gap(vmm)) return addr; addr = vmm->vm_end; if (flags & MAP_SHARED) diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index a062fe9a4e49..39f49991575e 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -117,7 +117,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi struct mm_struct *mm = current->mm; struct vm_area_struct * vma; unsigned long task_size = TASK_SIZE; - unsigned long start_addr; + unsigned long start_addr, vm_start; int do_color_align; if (flags & MAP_FIXED) { @@ -147,7 +147,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi vma = find_vma(mm, addr); if (task_size - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -181,15 +181,17 @@ full_search: } return -ENOMEM; } - if (likely(!vma || addr + len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* * Remember the place where we stopped the search: */ mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = vma->vm_end; if (do_color_align) @@ -205,7 +207,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, struct vm_area_struct *vma; struct mm_struct *mm = current->mm; unsigned long task_size = STACK_TOP32; - unsigned long addr = addr0; + unsigned long addr = addr0, vm_start; int do_color_align; /* This should only ever run for 32-bit processes. */ @@ -237,7 +239,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, vma = find_vma(mm, addr); if (task_size - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -258,7 +260,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, /* make sure it can fit in the remaining address space */ if (likely(addr > len)) { vma = find_vma(mm, addr-len); - if (!vma || addr <= vma->vm_start) { + if (!vma || addr <= vm_start_gap(vma)) { /* remember the address as a hint for next time */ return (mm->free_area_cache = addr-len); } @@ -278,20 +280,22 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, * return with success: */ vma = find_vma(mm, addr); - if (likely(!vma || addr+len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* remember the address as a hint for next time */ return (mm->free_area_cache = addr); } /* remember the largest hole we saw so far */ - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; /* try just below the current vma->vm_start */ - addr = vma->vm_start-len; + addr = vm_start - len; if (do_color_align) addr = COLOUR_ALIGN_DOWN(addr, pgoff); - } while (likely(len < vma->vm_start)); + } while (likely(len < vm_start)); bottomup: /* diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c index 07e14535375c..e13e85dbfcd9 100644 --- a/arch/sparc/mm/hugetlbpage.c +++ b/arch/sparc/mm/hugetlbpage.c @@ -33,7 +33,7 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp, struct mm_struct *mm = current->mm; struct vm_area_struct * vma; unsigned long task_size = TASK_SIZE; - unsigned long start_addr; + unsigned long start_addr, vm_start; if (test_thread_flag(TIF_32BIT)) task_size = STACK_TOP32; @@ -67,15 +67,17 @@ full_search: } return -ENOMEM; } - if (likely(!vma || addr + len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* * Remember the place where we stopped the search: */ mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = ALIGN(vma->vm_end, HPAGE_SIZE); } @@ -90,6 +92,7 @@ hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, struct vm_area_struct *vma; struct mm_struct *mm = current->mm; unsigned long addr = addr0; + unsigned long vm_start; /* This should only ever run for 32-bit processes. */ BUG_ON(!test_thread_flag(TIF_32BIT)); @@ -106,7 +109,7 @@ hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, /* make sure it can fit in the remaining address space */ if (likely(addr > len)) { vma = find_vma(mm, addr-len); - if (!vma || addr <= vma->vm_start) { + if (!vma || addr <= vm_start_gap(vma)) { /* remember the address as a hint for next time */ return (mm->free_area_cache = addr-len); } @@ -124,18 +127,20 @@ hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, * return with success: */ vma = find_vma(mm, addr); - if (likely(!vma || addr+len <= vma->vm_start)) { + if (vma) + vm_start = vm_start_gap(vma); + if (likely(!vma || addr + len <= vm_start)) { /* remember the address as a hint for next time */ return (mm->free_area_cache = addr); } /* remember the largest hole we saw so far */ - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; /* try just below the current vma->vm_start */ - addr = (vma->vm_start-len) & HPAGE_MASK; - } while (likely(len < vma->vm_start)); + addr = (vm_start - len) & HPAGE_MASK; + } while (likely(len < vm_start)); bottomup: /* @@ -182,7 +187,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, addr = ALIGN(addr, HPAGE_SIZE); vma = find_vma(mm, addr); if (task_size - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } if (mm->get_unmapped_area == arch_get_unmapped_area) diff --git a/arch/tile/mm/hugetlbpage.c b/arch/tile/mm/hugetlbpage.c index 42cfcba4e1ef..184e0339c056 100644 --- a/arch/tile/mm/hugetlbpage.c +++ b/arch/tile/mm/hugetlbpage.c @@ -159,7 +159,7 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file, struct hstate *h = hstate_file(file); struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - unsigned long start_addr; + unsigned long start_addr, vm_start; if (len > mm->cached_hole_size) { start_addr = mm->free_area_cache; @@ -185,12 +185,14 @@ full_search: } return -ENOMEM; } - if (!vma || addr + len <= vma->vm_start) { + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || addr + len <= vm_start) { mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = ALIGN(vma->vm_end, huge_page_size(h)); } } @@ -204,6 +206,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, struct vm_area_struct *vma, *prev_vma; unsigned long base = mm->mmap_base, addr = addr0; unsigned long largest_hole = mm->cached_hole_size; + unsigned long vm_start; int first_time = 1; /* don't allow allocations above current base */ @@ -234,9 +237,10 @@ try_again: /* * new region fits between prev_vma->vm_end and - * vma->vm_start, use it: + * vm_start, use it: */ - if (addr + len <= vma->vm_start && + vm_start = vm_start_gap(vma); + if (addr + len <= vm_start && (!prev_vma || (addr >= prev_vma->vm_end))) { /* remember the address as a hint for next time */ mm->cached_hole_size = largest_hole; @@ -251,13 +255,13 @@ try_again: } /* remember the largest hole we saw so far */ - if (addr + largest_hole < vma->vm_start) - largest_hole = vma->vm_start - addr; + if (addr + largest_hole < vm_start) + largest_hole = vm_start - addr; /* try just below the current vma->vm_start */ - addr = (vma->vm_start - len) & huge_page_mask(h); + addr = (vm_start - len) & huge_page_mask(h); - } while (len <= vma->vm_start); + } while (len <= vm_start); fail: /* @@ -312,7 +316,7 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, addr = ALIGN(addr, huge_page_size(h)); vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } if (current->mm->get_unmapped_area == arch_get_unmapped_area) diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index cdb2fc9235b7..0dbfff8e1a58 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -126,7 +126,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - unsigned long start_addr; + unsigned long start_addr, vm_start; unsigned long begin, end; if (flags & MAP_FIXED) @@ -141,7 +141,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, addr = PAGE_ALIGN(addr); vma = find_vma(mm, addr); if (end - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } if (((flags & MAP_32BIT) || test_thread_flag(TIF_IA32)) @@ -172,15 +172,17 @@ full_search: } return -ENOMEM; } - if (!vma || addr + len <= vma->vm_start) { + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || addr + len <= vm_start) { /* * Remember the place where we stopped the search: */ mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = vma->vm_end; addr = align_addr(addr, filp, 0); @@ -196,6 +198,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, struct vm_area_struct *vma; struct mm_struct *mm = current->mm; unsigned long addr = addr0; + unsigned long vm_start; /* requested length too big for entire address space */ if (len > TASK_SIZE) @@ -213,7 +216,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, addr = PAGE_ALIGN(addr); vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -232,7 +235,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, ALIGN_TOPDOWN); vma = find_vma(mm, tmp_addr); - if (!vma || tmp_addr + len <= vma->vm_start) + if (!vma || tmp_addr + len <= vm_start_gap(vma)) /* remember the address as a hint for next time */ return mm->free_area_cache = tmp_addr; } @@ -251,17 +254,19 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, * return with success: */ vma = find_vma(mm, addr); - if (!vma || addr+len <= vma->vm_start) + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || addr + len <= vm_start) /* remember the address as a hint for next time */ return mm->free_area_cache = addr; /* remember the largest hole we saw so far */ - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; /* try just below the current vma->vm_start */ - addr = vma->vm_start-len; - } while (len < vma->vm_start); + addr = vm_start - len; + } while (len < vm_start); bottomup: /* diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index df7d12c9af24..67b87605e223 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -277,7 +277,7 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file, struct hstate *h = hstate_file(file); struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - unsigned long start_addr; + unsigned long start_addr, vm_start; if (len > mm->cached_hole_size) { start_addr = mm->free_area_cache; @@ -303,12 +303,14 @@ full_search: } return -ENOMEM; } - if (!vma || addr + len <= vma->vm_start) { + if (vma) + vm_start = vm_start_gap(vma); + if (!vma || addr + len <= vm_start) { mm->free_area_cache = addr + len; return addr; } - if (addr + mm->cached_hole_size < vma->vm_start) - mm->cached_hole_size = vma->vm_start - addr; + if (addr + mm->cached_hole_size < vm_start) + mm->cached_hole_size = vm_start - addr; addr = ALIGN(vma->vm_end, huge_page_size(h)); } } @@ -322,6 +324,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, struct vm_area_struct *vma, *prev_vma; unsigned long base = mm->mmap_base, addr = addr0; unsigned long largest_hole = mm->cached_hole_size; + unsigned long vm_start; int first_time = 1; /* don't allow allocations above current base */ @@ -351,7 +354,8 @@ try_again: * new region fits between prev_vma->vm_end and * vma->vm_start, use it: */ - if (addr + len <= vma->vm_start && + vm_start = vm_start_gap(vma); + if (addr + len <= vm_start && (!prev_vma || (addr >= prev_vma->vm_end))) { /* remember the address as a hint for next time */ mm->cached_hole_size = largest_hole; @@ -365,12 +369,12 @@ try_again: } /* remember the largest hole we saw so far */ - if (addr + largest_hole < vma->vm_start) - largest_hole = vma->vm_start - addr; + if (addr + largest_hole < vm_start) + largest_hole = vm_start - addr; /* try just below the current vma->vm_start */ - addr = (vma->vm_start - len) & huge_page_mask(h); - } while (len <= vma->vm_start); + addr = (vm_start - len) & huge_page_mask(h); + } while (len <= vm_start); fail: /* @@ -426,7 +430,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, addr = ALIGN(addr, huge_page_size(h)); vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && - (!vma || addr + len <= vma->vm_start)) + (!vma || addr + len <= vm_start_gap(vma))) return addr; } if (mm->get_unmapped_area == arch_get_unmapped_area) |