diff options
| author | Andrew Morton <akpm@linux-foundation.org> | 2013-03-13 14:59:43 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-03-13 15:21:47 -0700 |
| commit | 6d7825b10dbeafd60627cd04291fb10ec2b5b973 (patch) | |
| tree | 665fe65bbb0f931dc5d89596c0c12d2569638ea3 | |
| parent | c8615d3716fe327c2540cf514a34b227dc9b39e8 (diff) | |
mm/fremap.c: fix oops on error path
If find_vma() fails, sys_remap_file_pages() will dereference `vma', which
contains NULL. Fix it by checking the pointer.
(We could alternatively check for err==0, but this seems more direct)
(The vm_flags change is to squish a bogus used-uninitialised warning
without adding extra code).
Reported-by: Tommi Rantala <tt.rantala@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/fremap.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/fremap.c b/mm/fremap.c index 0cd4c11488e..6a8da7ee85f 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -163,7 +163,8 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, * and that the remapped range is valid and fully within * the single existing vma. */ - if (!vma || !(vma->vm_flags & VM_SHARED)) + vm_flags = vma->vm_flags; + if (!vma || !(vm_flags & VM_SHARED)) goto out; if (!vma->vm_ops || !vma->vm_ops->remap_pages) @@ -254,7 +255,8 @@ get_write_lock: */ out: - vm_flags = vma->vm_flags; + if (vma) + vm_flags = vma->vm_flags; if (likely(!has_write_lock)) up_read(&mm->mmap_sem); else |