From 85e3f1adcb9d49300b0a943bb93f9604be375bfb Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 10 Nov 2017 04:27:39 +1100 Subject: powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation Radix VA space allocations test addresses against mm->task_size which is 512TB, even in cases where the intention is to limit allocation to below 128TB. This results in mmap with a hint address below 128TB but address + length above 128TB succeeding when it should fail (as hash does after the previous patch). Set the high address limit to be considered up front, and base subsequent allocation checks on that consistently. Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Nicholas Piggin Reviewed-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/mm/mmap.c | 55 ++++++++++++++++++++++++++++++-------------------- 1 file changed, 33 insertions(+), 22 deletions(-) (limited to 'arch/powerpc/mm/mmap.c') diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c index 5d78b193fec4..6d476a7b5611 100644 --- a/arch/powerpc/mm/mmap.c +++ b/arch/powerpc/mm/mmap.c @@ -106,22 +106,32 @@ radix__arch_get_unmapped_area(struct file *filp, unsigned long addr, { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; + int fixed = (flags & MAP_FIXED); + unsigned long high_limit; struct vm_unmapped_area_info info; + high_limit = DEFAULT_MAP_WINDOW; + if (addr >= high_limit || (fixed && (addr + len > high_limit))) + high_limit = TASK_SIZE; + + if (len > high_limit) + return -ENOMEM; + if (fixed) { + if (addr > high_limit - len) + return -ENOMEM; + } + if (unlikely(addr > mm->context.addr_limit && mm->context.addr_limit != TASK_SIZE)) mm->context.addr_limit = TASK_SIZE; - if (len > mm->task_size - mmap_min_addr) - return -ENOMEM; - - if (flags & MAP_FIXED) + if (fixed) return addr; if (addr) { addr = PAGE_ALIGN(addr); vma = find_vma(mm, addr); - if (mm->task_size - len >= addr && addr >= mmap_min_addr && + if (high_limit - len >= addr && addr >= mmap_min_addr && (!vma || addr + len <= vm_start_gap(vma))) return addr; } @@ -129,13 +139,9 @@ radix__arch_get_unmapped_area(struct file *filp, unsigned long addr, info.flags = 0; info.length = len; info.low_limit = mm->mmap_base; + info.high_limit = high_limit; info.align_mask = 0; - if (unlikely(addr > DEFAULT_MAP_WINDOW)) - info.high_limit = mm->context.addr_limit; - else - info.high_limit = DEFAULT_MAP_WINDOW; - return vm_unmapped_area(&info); } @@ -149,37 +155,42 @@ radix__arch_get_unmapped_area_topdown(struct file *filp, struct vm_area_struct *vma; struct mm_struct *mm = current->mm; unsigned long addr = addr0; + int fixed = (flags & MAP_FIXED); + unsigned long high_limit; struct vm_unmapped_area_info info; + high_limit = DEFAULT_MAP_WINDOW; + if (addr >= high_limit || (fixed && (addr + len > high_limit))) + high_limit = TASK_SIZE; + + if (len > high_limit) + return -ENOMEM; + if (fixed) { + if (addr > high_limit - len) + return -ENOMEM; + } + if (unlikely(addr > mm->context.addr_limit && mm->context.addr_limit != TASK_SIZE)) mm->context.addr_limit = TASK_SIZE; - /* requested length too big for entire address space */ - if (len > mm->task_size - mmap_min_addr) - return -ENOMEM; - - if (flags & MAP_FIXED) + if (fixed) return addr; - /* requesting a specific address */ if (addr) { addr = PAGE_ALIGN(addr); vma = find_vma(mm, addr); - if (mm->task_size - len >= addr && addr >= mmap_min_addr && - (!vma || addr + len <= vm_start_gap(vma))) + if (high_limit - len >= addr && addr >= mmap_min_addr && + (!vma || addr + len <= vm_start_gap(vma))) return addr; } info.flags = VM_UNMAPPED_AREA_TOPDOWN; info.length = len; info.low_limit = max(PAGE_SIZE, mmap_min_addr); - info.high_limit = mm->mmap_base; + info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW); info.align_mask = 0; - if (addr > DEFAULT_MAP_WINDOW) - info.high_limit += mm->context.addr_limit - DEFAULT_MAP_WINDOW; - addr = vm_unmapped_area(&info); if (!(addr & ~PAGE_MASK)) return addr; -- cgit v1.2.3-58-ga151