On Sat, 7 Aug 2021 17:22:25 +0200 Len Baker <len.baker@xxxxxxx> wrote: > strcpy() performs no bounds checking on the destination buffer. This > could result in linear overflows beyond the end of the buffer, leading > to all kinds of misbehaviors. The safe replacement is strscpy(). > > This patch is an effort to clean up the proliferation of str*() > functions in the kernel and a previous step in the path to remove > the strcpy function from the kernel entirely [1]. > > [1] https://github.com/KSPP/linux/issues/88 > > Signed-off-by: Len Baker <len.baker@xxxxxxx> Applied to the togreg branch of iio.git and pushed out as testing so 0-day can poke at it and see if we missed anything. Thanks, Jonathan > --- > Changelog v1 -> v2 > - Modify the commit changelog to inform that the motivation of this > patch is to remove the strcpy() function from the kernel entirely > (Jonathan Cameron). > > drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c > index f282e9cc34c5..3a6aa1c4bf6c 100644 > --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c > +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c > @@ -264,6 +264,7 @@ int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st) > const char *orient; > char *str; > int i; > + size_t n; > > /* fill magnetometer orientation */ > switch (st->chip_type) { > @@ -282,17 +283,18 @@ int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st) > for (i = 0; i < 3; ++i) { > orient = st->orientation.rotation[6 + i]; > /* use length + 2 for adding minus sign if needed */ > - str = devm_kzalloc(regmap_get_device(st->map), > - strlen(orient) + 2, GFP_KERNEL); > + n = strlen(orient) + 2; > + str = devm_kzalloc(regmap_get_device(st->map), n, > + GFP_KERNEL); > if (str == NULL) > return -ENOMEM; > if (strcmp(orient, "0") == 0) { > - strcpy(str, orient); > + strscpy(str, orient, n); > } else if (orient[0] == '-') { > - strcpy(str, &orient[1]); > + strscpy(str, &orient[1], n); > } else { > str[0] = '-'; > - strcpy(&str[1], orient); > + strscpy(&str[1], orient, n - 1); > } > st->magn_orient.rotation[6 + i] = str; > } > -- > 2.25.1 >
