lkml.org 
[lkml]   [2012]   [Aug]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH] iio/adjd_s311: Fix potential memory leak in adjd_s311_update_scan_mode()

    > Do not leak memory by updating pointer with potentially
    > NULL realloc return value.

    I agree

    use of krealloc() was suggested in driver review (see
    http://www.spinics.net/lists/linux-iio/msg05930.html) to shorten the code;
    unfortunately, I misunderstood the semantics of krealloc() in case
    allocation fails

    this is the original code:

    kfree(data->buffer);
    data->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
    if (!data->buffer)
    return -ENOMEM;

    I suggest to switch back to that original code, there is no need preserve
    the data in the buffer as krealloc does

    thanks, p.

    > Found by Linux Driver Verification project (linuxtesting.org).
    >
    > Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
    > ---
    > drivers/iio/light/adjd_s311.c | 14 ++++++++++----
    > 1 file changed, 10 insertions(+), 4 deletions(-)
    >
    > diff --git a/drivers/iio/light/adjd_s311.c b/drivers/iio/light/adjd_s311.c
    > index 1cbb449..0adda5b 100644
    > --- a/drivers/iio/light/adjd_s311.c
    > +++ b/drivers/iio/light/adjd_s311.c
    > @@ -271,12 +271,18 @@ static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
    > const unsigned long *scan_mask)
    > {
    > struct adjd_s311_data *data = iio_priv(indio_dev);
    > - data->buffer = krealloc(data->buffer, indio_dev->scan_bytes,
    > + u16 *new_buffer;
    > + int ret = 0;
    > +
    > + new_buffer = krealloc(data->buffer, indio_dev->scan_bytes,
    > GFP_KERNEL);
    > - if (!data->buffer)
    > - return -ENOMEM;
    > + if (new_buffer == NULL) {
    > + kfree(data->buffer);
    > + ret = -ENOMEM;
    > + }
    > + data->buffer = new_buffer;
    >
    > - return 0;
    > + return ret;
    > }
    >
    > static const struct iio_info adjd_s311_info = {
    >

    --

    Peter Meerwald
    +43-664-2444418 (mobile)


    \
     
     \ /
      Last update: 2012-08-08 10:02    [W:0.022 / U:5.284 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site