summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorPunit Agrawal <punitagrawal@gmail.com>2021-09-14 23:38:46 +0900
committerSteven Rostedt (VMware) <rostedt@goodmis.org>2021-09-30 21:24:04 -0400
commit5d6de7d7fb4b0f752adff80ca003b4fd4b467b64 (patch)
tree60d15a4284316f5e38b2bb2ed7caeecf9a1e857c
parent8f7262cd66699a4b02eb7549b35c81b2116aad95 (diff)
kprobes: Use helper to parse boolean input from userspace
The "enabled" file provides a debugfs interface to arm / disarm kprobes in the kernel. In order to parse the buffer containing the values written from userspace, the callback manually parses the user input to convert it to a boolean value. As taking a string value from userspace and converting it to boolean is a common operation, a helper kstrtobool_from_user() is already available in the kernel. Update the callback to use the common helper to parse the write buffer from userspace. Link: https://lkml.kernel.org/r/163163032637.489837.10678039554832855327.stgit@devnote2 Signed-off-by: Punit Agrawal <punitagrawal@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-rw-r--r--kernel/kprobes.c28
1 files changed, 6 insertions, 22 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 1cf8bca1ea86..26fc9904c3b1 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2770,30 +2770,14 @@ static ssize_t read_enabled_file_bool(struct file *file,
static ssize_t write_enabled_file_bool(struct file *file,
const char __user *user_buf, size_t count, loff_t *ppos)
{
- char buf[32];
- size_t buf_size;
- int ret = 0;
-
- buf_size = min(count, (sizeof(buf)-1));
- if (copy_from_user(buf, user_buf, buf_size))
- return -EFAULT;
+ bool enable;
+ int ret;
- buf[buf_size] = '\0';
- switch (buf[0]) {
- case 'y':
- case 'Y':
- case '1':
- ret = arm_all_kprobes();
- break;
- case 'n':
- case 'N':
- case '0':
- ret = disarm_all_kprobes();
- break;
- default:
- return -EINVAL;
- }
+ ret = kstrtobool_from_user(user_buf, count, &enable);
+ if (ret)
+ return ret;
+ ret = enable ? arm_all_kprobes() : disarm_all_kprobes();
if (ret)
return ret;