diff options
| author | Thorsten Blum <thorsten.blum@linux.dev> | 2025-09-05 13:02:23 +0200 |
|---|---|---|
| committer | Alexander Gordeev <agordeev@linux.ibm.com> | 2025-09-09 15:03:13 +0200 |
| commit | 5450abb0dea4f9fb432dea2ca92ea7a9bd25650b (patch) | |
| tree | 746b60fda6ef04ea41d25588d7b55f6b2d1fe44b | |
| parent | f5507aefc9114ced49d1ee527f63ea12ff5d7751 (diff) | |
s390/hmcdrv: Replace kmalloc() + copy_from_user() with memdup_user_nul()
Replace kmalloc() followed by copy_from_user() with memdup_user_nul() to
improve and simplify hmcdrv_dev_write(). Remove the manual
NUL-termination.
No functional changes intended.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
| -rw-r--r-- | drivers/s390/char/hmcdrv_dev.c | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/drivers/s390/char/hmcdrv_dev.c b/drivers/s390/char/hmcdrv_dev.c index e069dd685899..b26fcf6849f2 100644 --- a/drivers/s390/char/hmcdrv_dev.c +++ b/drivers/s390/char/hmcdrv_dev.c @@ -244,24 +244,17 @@ static ssize_t hmcdrv_dev_write(struct file *fp, const char __user *ubuf, size_t len, loff_t *pos) { ssize_t retlen; + void *pdata; pr_debug("writing file '/dev/%pD' at pos. %lld with length %zd\n", fp, (long long) *pos, len); if (!fp->private_data) { /* first expect a cmd write */ - fp->private_data = kmalloc(len + 1, GFP_KERNEL); - - if (!fp->private_data) - return -ENOMEM; - - if (!copy_from_user(fp->private_data, ubuf, len)) { - ((char *)fp->private_data)[len] = '\0'; - return len; - } - - kfree(fp->private_data); - fp->private_data = NULL; - return -EFAULT; + pdata = memdup_user_nul(ubuf, len); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + fp->private_data = pdata; + return len; } retlen = hmcdrv_dev_transfer((char *) fp->private_data, |