diff options
| author |   H Hartley Sweeten <hsweeten@visionengravers.com> | 2015-04-20 11:49:04 -0700 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-04-30 17:15:59 +0200 |
| commit | b3ab6fbfd8625232c54d70e29f7274118726ba45 (patch) | |
| tree | 0fba04198fc5c44d0005a8a7ee4129a75151f06c | |
| parent | Staging: comedi: daqboard2000.c fixed trailing whitespace (diff) | |
staging: comedi: comedi_bond: fix 'b_mask' calc in bonding_dio_insn_bits()
'b_chans' may be a valud up to 32. 'b_mask' is an unsigned int and a left shift of
more than 31 bits has undefined behavior. Fix the calc so it works correctly with
a 'b_chans' of 32..
Reported-by: coverity (CID 1192244)
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/comedi/drivers/comedi_bond.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/staging/comedi/drivers/comedi_bond.c b/drivers/staging/comedi/drivers/comedi_bond.c index 96db0c2686a1..50b76eccb7d7 100644 --- a/drivers/staging/comedi/drivers/comedi_bond.c +++ b/drivers/staging/comedi/drivers/comedi_bond.c @@ -101,7 +101,8 @@ static int bonding_dio_insn_bits(struct comedi_device *dev, b_chans = bdev->nchans - base_chan; if (b_chans > n_left) b_chans = n_left; - b_mask = (1U << b_chans) - 1; + b_mask = (b_chans < 32) ? ((1 << b_chans) - 1) + : 0xffffffff; b_write_mask = (write_mask >> n_done) & b_mask; b_data_bits = (data_bits >> n_done) & b_mask; /* Read/Write the new digital lines. */ |