shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-10 12:57:06 +09:00
Code Issues Packages Projects Releases Wiki Activity

aio: check for multiplication overflow in do_io_submit

Browse Source 
commit 75e1c70fc3 upstream.

Tavis Ormandy pointed out that do_io_submit does not do proper bounds
checking on the passed-in iocb array:

       if (unlikely(nr < 0))
               return -EINVAL;

       if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(iocbpp)))))
               return -EFAULT;                      ^^^^^^^^^^^^^^^^^^

The attached patch checks for overflow, and if it is detected, the
number of iocbs submitted is scaled down to a number that will fit in
the long.  This is an ok thing to do, as sys_io_submit is documented as
returning the number of iocbs submitted, so callers should handle a
return value of less than the 'nr' argument passed in.

Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jeff Moyer
2010-09-10 14:16:00 -07:00
committed by Greg Kroah-Hartman
parent 61e0ce1b36
commit 02e33709e1
1 changed files with 3 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
fs/aio.c
View File

@@ -1639,6 +1639,9 @@ SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr,
if (unlikely(nr < 0))
return -EINVAL;
if (unlikely(nr > LONG_MAX/sizeof(*iocbpp)))
nr = LONG_MAX/sizeof(*iocbpp);
if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(*iocbpp)))))
return -EFAULT;