Implement ->proc_write_buf() so procfs copies in what is written before
it pins the entry, and parse the level from that copy. Writes larger
than PAGE_SIZE - 1 bytes fail with -EINVAL now, and a buffer that can't
be read fails with -EFAULT instead of looking like it was written.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
---
drivers/net/wireless/intel/ipw2x00/libipw_module.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/intel/ipw2x00/libipw_module.c b/drivers/net/wireless/intel/ipw2x00/libipw_module.c
index 15d9a5efb581..08cc0d7f57c1 100644
--- a/drivers/net/wireless/intel/ipw2x00/libipw_module.c
+++ b/drivers/net/wireless/intel/ipw2x00/libipw_module.c
@@ -216,14 +216,13 @@ static int debug_level_proc_show(struct seq_file *m, void *v)
}
static ssize_t debug_level_proc_write(struct file *file,
- const char __user *buffer, size_t count, loff_t *pos)
+ char *buffer, size_t count, loff_t *pos)
{
char buf[] = "0x00000000\n";
size_t len = min(sizeof(buf) - 1, count);
unsigned long val;
- if (copy_from_user(buf, buffer, len))
- return count;
+ memcpy(buf, buffer, len);
buf[len] = 0;
if (sscanf(buf, "%li", &val) != 1)
printk(KERN_INFO DRV_NAME@@ -236,7 +235,7 @@ static ssize_t debug_level_proc_write(struct file *file,
static const struct proc_ops debug_level_proc_ops = {
.proc_show = debug_level_proc_show,
- .proc_write = debug_level_proc_write,
+ .proc_write_buf = debug_level_proc_write,
};
#endif /* CONFIG_LIBIPW_DEBUG */
--
2.53.0