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author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-11-26 18:06:46 +0100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-27 08:47:39 +0100 |
commit | 8d4a8bb7f8547297bcce5502f6ff382c408bd9ee (patch) | |
tree | 550ed56b2b79409ff8b2470f5145e1aef4249af1 | |
parent | 6671b609ebcd4518da4527fe534a171f18dc6393 (diff) | |
download | linux-stable-8d4a8bb7f8547297bcce5502f6ff382c408bd9ee.tar.gz linux-stable-8d4a8bb7f8547297bcce5502f6ff382c408bd9ee.tar.bz2 linux-stable-8d4a8bb7f8547297bcce5502f6ff382c408bd9ee.zip |
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@intel.com/T/
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/d14ed8d71ad4372e6839ae427f91441d3ba0e94d.1637946316.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | drivers/w1/slaves/w1_ds28e04.c | 26 |
1 files changed, 6 insertions, 20 deletions
diff --git a/drivers/w1/slaves/w1_ds28e04.c b/drivers/w1/slaves/w1_ds28e04.c index 5e348d38ec5c..f4cf54c256fd 100644 --- a/drivers/w1/slaves/w1_ds28e04.c +++ b/drivers/w1/slaves/w1_ds28e04.c @@ -39,7 +39,7 @@ 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 @@ -346,32 +346,18 @@ 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); |