This function is only used by elf_load(), and that is a static function
that doesn't need an exported symbol to invoke an internal function, so
un-EXPORT_SYMBOLS() it.

Also, the vm_flags parameter is unnecessary, as we only ever set VM_EXEC,
so simply make this parameter a boolean.

While we're here, clean up the mm.h definitions for the various vm_xxx()
helpers so we actually specify parameter names and elide the redundant
extern's.

Signed-off-by: Lorenzo Stoakes (Oracle) <[email protected]>
---
 fs/binfmt_elf.c    |  3 +--
 include/linux/mm.h | 12 ++++++------
 mm/mmap.c          |  8 ++------
 3 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index fb857faaf0d6..16a56b6b3f6c 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -453,14 +453,13 @@ static unsigned long elf_load(struct file *filep, 
unsigned long addr,
                zero_end = ELF_PAGEALIGN(zero_end);
 
                error = vm_brk_flags(zero_start, zero_end - zero_start,
-                                    prot & PROT_EXEC ? VM_EXEC : 0);
+                                    prot & PROT_EXEC);
                if (error)
                        map_addr = error;
        }
        return map_addr;
 }
 
-
 static unsigned long total_mapping_size(const struct elf_phdr *phdr, int nr)
 {
        elf_addr_t min_addr = -1;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5a287e58c1e6..2c16c744d49d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3985,12 +3985,12 @@ static inline void mm_populate(unsigned long addr, 
unsigned long len) {}
 #endif
 
 /* This takes the mm semaphore itself */
-extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned 
long);
-extern int vm_munmap(unsigned long, size_t);
-extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
-        unsigned long, unsigned long,
-        unsigned long, unsigned long);
-extern unsigned long __must_check vm_mmap_shadow_stack(unsigned long addr,
+int __must_check vm_brk_flags(unsigned long addr, unsigned long request, bool 
is_exec);
+int vm_munmap(unsigned long start, size_t len);
+unsigned long __must_check vm_mmap(struct file *file, unsigned long addr,
+               unsigned long len, unsigned long prot,
+               unsigned long flag, unsigned long offset);
+unsigned long __must_check vm_mmap_shadow_stack(unsigned long addr,
                unsigned long len, unsigned long flags);
 
 struct vm_unmapped_area_info {
diff --git a/mm/mmap.c b/mm/mmap.c
index 843160946aa5..2a0721e75988 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1201,8 +1201,9 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, 
unsigned long, size,
        return ret;
 }
 
-int vm_brk_flags(unsigned long addr, unsigned long request, vm_flags_t 
vm_flags)
+int vm_brk_flags(unsigned long addr, unsigned long request, bool is_exec)
 {
+       const vm_flags_t vm_flags = is_exec ? VM_EXEC : 0;
        struct mm_struct *mm = current->mm;
        struct vm_area_struct *vma = NULL;
        unsigned long len;
@@ -1217,10 +1218,6 @@ int vm_brk_flags(unsigned long addr, unsigned long 
request, vm_flags_t vm_flags)
        if (!len)
                return 0;
 
-       /* Until we need other flags, refuse anything except VM_EXEC. */
-       if ((vm_flags & (~VM_EXEC)) != 0)
-               return -EINVAL;
-
        if (mmap_write_lock_killable(mm))
                return -EINTR;
 
@@ -1246,7 +1243,6 @@ int vm_brk_flags(unsigned long addr, unsigned long 
request, vm_flags_t vm_flags)
        mmap_write_unlock(mm);
        return ret;
 }
-EXPORT_SYMBOL(vm_brk_flags);
 
 static
 unsigned long tear_down_vmas(struct mm_struct *mm, struct vma_iterator *vmi,
-- 
2.53.0


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