summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorIan Abbott <abbotti@mev.co.uk>2025-07-07 13:15:55 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-07-16 14:59:01 +0200
commitab705c8c35e18652abc6239c07cf3441f03e2cda (patch)
treef5a7aba3a4e34729dd234ee41ec94a31e95fdf2a
parent08ae4b20f5e82101d77326ecab9089e110f224cc (diff)
comedi: Fix some signed shift left operations
Correct some left shifts of the signed integer constant 1 by some unsigned number less than 32. Change the constant to 1U to avoid shifting a 1 into the sign bit. The corrected functions are comedi_dio_insn_config(), comedi_dio_update_state(), and __comedi_device_postconfig(). Fixes: e523c6c86232 ("staging: comedi: drivers: introduce comedi_dio_insn_config()") Fixes: 05e60b13a36b ("staging: comedi: drivers: introduce comedi_dio_update_state()") Fixes: 09567cb4373e ("staging: comedi: initialize subdevice s->io_bits in postconfig") Cc: stable@vger.kernel.org # 5.13+ Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Link: https://lore.kernel.org/r/20250707121555.65424-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/comedi/drivers.c14
1 files changed, 7 insertions, 7 deletions
diff --git a/drivers/comedi/drivers.c b/drivers/comedi/drivers.c
index 376130bfba8a..922fe20738ef 100644
--- a/drivers/comedi/drivers.c
+++ b/drivers/comedi/drivers.c
@@ -339,10 +339,10 @@ int comedi_dio_insn_config(struct comedi_device *dev,
unsigned int *data,
unsigned int mask)
{
- unsigned int chan_mask = 1 << CR_CHAN(insn->chanspec);
+ unsigned int chan = CR_CHAN(insn->chanspec);
- if (!mask)
- mask = chan_mask;
+ if (!mask && chan < 32)
+ mask = 1U << chan;
switch (data[0]) {
case INSN_CONFIG_DIO_INPUT:
@@ -382,7 +382,7 @@ EXPORT_SYMBOL_GPL(comedi_dio_insn_config);
unsigned int comedi_dio_update_state(struct comedi_subdevice *s,
unsigned int *data)
{
- unsigned int chanmask = (s->n_chan < 32) ? ((1 << s->n_chan) - 1)
+ unsigned int chanmask = (s->n_chan < 32) ? ((1U << s->n_chan) - 1)
: 0xffffffff;
unsigned int mask = data[0] & chanmask;
unsigned int bits = data[1];
@@ -625,8 +625,8 @@ static int insn_rw_emulate_bits(struct comedi_device *dev,
if (insn->insn == INSN_WRITE) {
if (!(s->subdev_flags & SDF_WRITABLE))
return -EINVAL;
- _data[0] = 1 << (chan - base_chan); /* mask */
- _data[1] = data[0] ? (1 << (chan - base_chan)) : 0; /* bits */
+ _data[0] = 1U << (chan - base_chan); /* mask */
+ _data[1] = data[0] ? (1U << (chan - base_chan)) : 0; /* bits */
}
ret = s->insn_bits(dev, s, &_insn, _data);
@@ -709,7 +709,7 @@ static int __comedi_device_postconfig(struct comedi_device *dev)
if (s->type == COMEDI_SUBD_DO) {
if (s->n_chan < 32)
- s->io_bits = (1 << s->n_chan) - 1;
+ s->io_bits = (1U << s->n_chan) - 1;
else
s->io_bits = 0xffffffff;
}