Hi Joe, On Sun, Aug 15, 2021 at 08:06:45AM -0700, Joe Perches wrote: > On Sat, 2021-08-14 at 22:36 +0300, Andy Shevchenko wrote: > > On Sat, Aug 14, 2021 at 4:55 PM 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. So, remove all the uses and add > > > devm_kstrdup() or devm_kasprintf() instead. > > > > > > 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 > > > > Thank you very much for doing this! > > Now I like the result, > > Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> > [] > > > diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_magn.c > [] > > > @@ -261,6 +261,7 @@ int inv_mpu_magn_set_rate(const struct inv_mpu6050_state *st, int fifo_rate) > > > */ > > > int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st) > > > { > > > + struct device *dev = regmap_get_device(st->map); > > > const char *orient; > > > char *str; > > > int i; > > > @@ -281,19 +282,24 @@ int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st) > > > /* z <- -z */ > > > 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); > > > - if (str == NULL) > > > + > > > + /* > > > + * The value is negated according to one of the following > > > + * rules: > > > + * > > > + * 1) Drop leading minus. > > > + * 2) Leave 0 as is. > > > + * 3) Add leading minus. > > > + */ > > > + if (orient[0] == '-') > > > + str = devm_kstrdup(dev, orient + 1, GFP_KERNEL); > > > + else if (orient[0] == '0' && orient[1] == '\0') > > bikeshed: > > I think this change is less intelligible than the original strcmp. So, if I understand correctly you suggest to change the above line for: else if (strcmp(orient, "0") == 0) And yes, this line will be more readable ;) > > And separately, perhaps for loop would be more readable as > > for (i = 6; i < 9; i++) > > converting the 6 + i uses to just i. Ok, no problem. If there are no objections I will send a new version with these 2 changes. Regards, Len > > > > + str = devm_kstrdup(dev, orient, GFP_KERNEL); > > > + else > > > + str = devm_kasprintf(dev, GFP_KERNEL, "-%s", orient); > > > + if (!str) > > > return -ENOMEM; > > > - if (strcmp(orient, "0") == 0) { > > > - strcpy(str, orient); > > > - } else if (orient[0] == '-') { > > > - strcpy(str, &orient[1]); > > > - } else { > > > - str[0] = '-'; > > > - strcpy(&str[1], orient); > > > - } > > > + > > > st->magn_orient.rotation[6 + i] = str; > > > } > > > break; > >
