diff options
Diffstat (limited to 'drivers/hid/uhid.c')
| -rw-r--r-- | drivers/hid/uhid.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c index 7f8ff39ed44b..d02ee5304217 100644 --- a/drivers/hid/uhid.c +++ b/drivers/hid/uhid.c @@ -12,6 +12,7 @@ #include <linux/atomic.h> #include <linux/compat.h> +#include <linux/cred.h> #include <linux/device.h> #include <linux/fs.h> #include <linux/hid.h> @@ -24,6 +25,7 @@ #include <linux/spinlock.h> #include <linux/uhid.h> #include <linux/wait.h> +#include <linux/uaccess.h> #define UHID_NAME "uhid" #define UHID_BUFSIZE 32 @@ -721,6 +723,17 @@ static ssize_t uhid_char_write(struct file *file, const char __user *buffer, switch (uhid->input_buf.type) { case UHID_CREATE: + /* + * 'struct uhid_create_req' contains a __user pointer which is + * copied from, so it's unsafe to allow this with elevated + * privileges (e.g. from a setuid binary) or via kernel_write(). + */ + if (file->f_cred != current_cred() || uaccess_kernel()) { + pr_err_once("UHID_CREATE from different security context by process %d (%s), this is not allowed.\n", + task_tgid_vnr(current), current->comm); + ret = -EACCES; + goto unlock; + } ret = uhid_dev_create(uhid, &uhid->input_buf); break; case UHID_CREATE2: |