This is a note to let you know that I've just added the patch titled w1: Misuse of get_user()/put_user() reported by sparse to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: w1-misuse-of-get_user-put_user-reported-by-sparse.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ebda90d3d373069677d5a897b9257a8d6d8ba238 Author: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Date: Fri Nov 26 18:06:46 2021 +0100 w1: Misuse of get_user()/put_user() reported by sparse [ Upstream commit 33dc3e3e99e626ce51f462d883b05856c6c30b1d ] sparse warnings: (new ones prefixed by >>) >> drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected char [noderef] __user *_pu_addr @@ got char *buf @@ drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: expected char [noderef] __user *_pu_addr drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: got char *buf >> drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected char const [noderef] __user *_gu_addr @@ got char const *buf @@ drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: expected char const [noderef] __user *_gu_addr drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: got char const *buf The buffer buf is a failsafe buffer in kernel space, it's not user memory hence doesn't deserve the use of get_user() or put_user(). Access 'buf' content directly. Link: https://lore.kernel.org/lkml/202111190526.K5vb7NWC-lkp@xxxxxxxxx/T/ Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Link: https://lore.kernel.org/r/d14ed8d71ad4372e6839ae427f91441d3ba0e94d.1637946316.git.christophe.leroy@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/w1/slaves/w1_ds28e04.c b/drivers/w1/slaves/w1_ds28e04.c index e4f336111edc6..6cef6e2edb892 100644 --- a/drivers/w1/slaves/w1_ds28e04.c +++ b/drivers/w1/slaves/w1_ds28e04.c @@ -32,7 +32,7 @@ static int w1_strong_pullup = 1; module_param_named(strong_pullup, w1_strong_pullup, int, 0); /* enable/disable CRC checking on DS28E04-100 memory accesses */ -static char w1_enable_crccheck = 1; +static bool w1_enable_crccheck = true; #define W1_EEPROM_SIZE 512 #define W1_PAGE_COUNT 16 @@ -339,32 +339,18 @@ static BIN_ATTR_RW(pio, 1); static ssize_t crccheck_show(struct device *dev, struct device_attribute *attr, char *buf) { - if (put_user(w1_enable_crccheck + 0x30, buf)) - return -EFAULT; - - return sizeof(w1_enable_crccheck); + return sysfs_emit(buf, "%d\n", w1_enable_crccheck); } static ssize_t crccheck_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { - char val; - - if (count != 1 || !buf) - return -EINVAL; + int err = kstrtobool(buf, &w1_enable_crccheck); - if (get_user(val, buf)) - return -EFAULT; + if (err) + return err; - /* convert to decimal */ - val = val - 0x30; - if (val != 0 && val != 1) - return -EINVAL; - - /* set the new value */ - w1_enable_crccheck = val; - - return sizeof(w1_enable_crccheck); + return count; } static DEVICE_ATTR_RW(crccheck);