diff options
author | Jun Yan <jerrysteve1101@gmail.com> | 2024-12-12 22:38:52 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-23 18:50:41 +0100 |
commit | 7a3d76a0b60b3f6fc3375e4de2174bab43f64545 (patch) | |
tree | a15560c27b155eaf5325be3f5ed20a9bc032bac4 | |
parent | 057bd54dfcf68b1f67e6dfc32a47a72e12198495 (diff) |
USB: usblp: return error when setting unsupported protocol
Fix the regression introduced by commit d8c6edfa3f4e ("USB:
usblp: don't call usb_set_interface if there's a single alt"),
which causes that unsupported protocols can also be set via
ioctl when the num_altsetting of the device is 1.
Move the check for protocol support to the earlier stage.
Fixes: d8c6edfa3f4e ("USB: usblp: don't call usb_set_interface if there's a single alt")
Cc: stable <stable@kernel.org>
Signed-off-by: Jun Yan <jerrysteve1101@gmail.com>
Link: https://lore.kernel.org/r/20241212143852.671889-1-jerrysteve1101@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/usb/class/usblp.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c index 5a2e43331064..ff1a941fd2ed 100644 --- a/drivers/usb/class/usblp.c +++ b/drivers/usb/class/usblp.c @@ -1337,11 +1337,12 @@ static int usblp_set_protocol(struct usblp *usblp, int protocol) if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL) return -EINVAL; + alts = usblp->protocol[protocol].alt_setting; + if (alts < 0) + return -EINVAL; + /* Don't unnecessarily set the interface if there's a single alt. */ if (usblp->intf->num_altsetting > 1) { - alts = usblp->protocol[protocol].alt_setting; - if (alts < 0) - return -EINVAL; r = usb_set_interface(usblp->dev, usblp->ifnum, alts); if (r < 0) { printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n", |