The problem is that we change "p_args" to point to the middle of the
string so when we free it at the end of the function it's not freeing
the same pointer that we originally allocated.

Fixes: e2c94d6f5720 ("w1_therm: adding alarm sysfs entry")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
---
>From static analysis.  I guess it must not cause too much of a problem
at run time?

 drivers/w1/slaves/w1_therm.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
index cc4b88056b33..a6c85e486671 100644
--- a/drivers/w1/slaves/w1_therm.c
+++ b/drivers/w1/slaves/w1_therm.c
@@ -1526,8 +1526,9 @@ static ssize_t alarms_store(struct device *device,
        int temp, ret = -EINVAL;
        char *token = NULL;
        s8 tl, th, tt;  /* 1 byte per value + temp ring order */
-       char *p_args = kmalloc(size, GFP_KERNEL);
+       char *p_args, *orig;
 
+       p_args = orig = kmalloc(size, GFP_KERNEL);
        /* Safe string copys as buf is const */
        if (!p_args) {
                dev_warn(device,
@@ -1611,7 +1612,7 @@ static ssize_t alarms_store(struct device *device,
 
 free_m:
        /* free allocated memory */
-       kfree(p_args);
+       kfree(orig);
 
        return size;
 }
-- 
2.26.2

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