redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

mm/fremap.c: fix oops on error path

Browse source 
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>
This commit is contained in:
Andrew Morton 2013-03-13 14:59:43 -07:00 committed by Linus Torvalds
parent c8615d3716
commit 6d7825b10d
1 changed files with 4 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
mm/fremap.c
View file

@ -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