diff options
| -rw-r--r-- | arch/alpha/include/uapi/asm/mman.h | 1 | ||||
| -rw-r--r-- | arch/mips/include/uapi/asm/mman.h | 1 | ||||
| -rw-r--r-- | arch/parisc/include/uapi/asm/mman.h | 1 | ||||
| -rw-r--r-- | arch/xtensa/include/uapi/asm/mman.h | 1 | ||||
| -rw-r--r-- | include/uapi/asm-generic/mman-common.h | 1 | ||||
| -rw-r--r-- | mm/mmap.c | 11 |
6 files changed, 16 insertions, 0 deletions
diff --git a/arch/alpha/include/uapi/asm/mman.h b/arch/alpha/include/uapi/asm/mman.h index 2dbdf59258d9..f9d4e6b6d4bd 100644 --- a/arch/alpha/include/uapi/asm/mman.h +++ b/arch/alpha/include/uapi/asm/mman.h @@ -32,6 +32,7 @@ #define MAP_NONBLOCK 0x40000 /* do not block on IO */ #define MAP_STACK 0x80000 /* give out an address that is best suited for process/thread stacks */ #define MAP_HUGETLB 0x100000 /* create a huge page mapping */ +#define MAP_FIXED_NOREPLACE 0x200000/* MAP_FIXED which doesn't unmap underlying mapping */ #define MS_ASYNC 1 /* sync memory asynchronously */ #define MS_SYNC 2 /* synchronous memory sync */ diff --git a/arch/mips/include/uapi/asm/mman.h b/arch/mips/include/uapi/asm/mman.h index 606e02ca4b6c..3035ca499cd8 100644 --- a/arch/mips/include/uapi/asm/mman.h +++ b/arch/mips/include/uapi/asm/mman.h @@ -50,6 +50,7 @@ #define MAP_NONBLOCK 0x20000 /* do not block on IO */ #define MAP_STACK 0x40000 /* give out an address that is best suited for process/thread stacks */ #define MAP_HUGETLB 0x80000 /* create a huge page mapping */ +#define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ /* * Flags for msync diff --git a/arch/parisc/include/uapi/asm/mman.h b/arch/parisc/include/uapi/asm/mman.h index a056a642bb31..870fbf8c7088 100644 --- a/arch/parisc/include/uapi/asm/mman.h +++ b/arch/parisc/include/uapi/asm/mman.h @@ -26,6 +26,7 @@ #define MAP_NONBLOCK 0x20000 /* do not block on IO */ #define MAP_STACK 0x40000 /* give out an address that is best suited for process/thread stacks */ #define MAP_HUGETLB 0x80000 /* create a huge page mapping */ +#define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ #define MS_SYNC 1 /* synchronous memory sync */ #define MS_ASYNC 2 /* sync memory asynchronously */ diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h index 3e9d01ada81f..58f29a9d895d 100644 --- a/arch/xtensa/include/uapi/asm/mman.h +++ b/arch/xtensa/include/uapi/asm/mman.h @@ -57,6 +57,7 @@ #define MAP_NONBLOCK 0x20000 /* do not block on IO */ #define MAP_STACK 0x40000 /* give out an address that is best suited for process/thread stacks */ #define MAP_HUGETLB 0x80000 /* create a huge page mapping */ +#define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */ #ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED # define MAP_UNINITIALIZED 0x4000000 /* For anonymous mmap, memory could be * uninitialized */ diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h index f8b134f5608f..4aa65a8d7e92 100644 --- a/include/uapi/asm-generic/mman-common.h +++ b/include/uapi/asm-generic/mman-common.h @@ -26,6 +26,7 @@ #else # define MAP_UNINITIALIZED 0x0 /* Don't support this flag */ #endif +#define MAP_FIXED_NOREPLACE 0x80000 /* MAP_FIXED which doesn't unmap underlying mapping */ /* * Flags for mlock diff --git a/mm/mmap.c b/mm/mmap.c index f2154fc2548b..188f195883b9 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1342,6 +1342,10 @@ unsigned long do_mmap(struct file *file, unsigned long addr, if (!(file && path_noexec(&file->f_path))) prot |= PROT_EXEC; + /* force arch specific MAP_FIXED handling in get_unmapped_area */ + if (flags & MAP_FIXED_NOREPLACE) + flags |= MAP_FIXED; + if (!(flags & MAP_FIXED)) addr = round_hint_to_min(addr); @@ -1365,6 +1369,13 @@ unsigned long do_mmap(struct file *file, unsigned long addr, if (offset_in_page(addr)) return addr; + if (flags & MAP_FIXED_NOREPLACE) { + struct vm_area_struct *vma = find_vma(mm, addr); + + if (vma && vma->vm_start <= addr) + return -EEXIST; + } + if (prot == PROT_EXEC) { pkey = execute_only_pkey(mm); if (pkey < 0) |