| Message ID | 20250411111548.31399-1-purvayeshi550@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | tty: vt: keyboard: Fix uninitialized variables in vt_do_kdgkb_ioctl | expand |
diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c index ae92e6a50a65..d476c2e3f3d3 100644 --- a/drivers/tty/vt/keyboard.c +++ b/drivers/tty/vt/keyboard.c @@ -2057,8 +2057,8 @@ int vt_do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm) { unsigned char kb_func; unsigned long flags; - char *kbs; - int ret; + char *kbs = NULL; + int ret = -EINVAL; if (get_user(kb_func, &user_kdgkb->kb_func)) return -EFAULT; @@ -2101,6 +2101,10 @@ int vt_do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm) ret = 0; break; + + default: + /* unknown command, ret already set to -EINVAL */ + break; } kfree(kbs);
Fix Smatch-detected issue: drivers/tty/vt/keyboard.c:2106 vt_do_kdgkb_ioctl() error: uninitialized symbol 'kbs'. drivers/tty/vt/keyboard.c:2108 vt_do_kdgkb_ioctl() error: uninitialized symbol 'ret'. Fix uninitialized variable warnings reported by Smatch in vt_do_kdgkb_ioctl(). The variables kbs and ret were used in the kfree and return statements without guaranteed initialization paths, leading to potential undefined behavior or false positives during static analysis. Initialize char *kbs to NULL and int ret to -EINVAL at declaration. This ensures safe use of kfree(kbs) and return ret regardless of control flow. Also add a default case in the switch to preserve fallback behavior. Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com> --- drivers/tty/vt/keyboard.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)