6.17-stable review patch. If anyone has any objections, please let me know.
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From: Douglas Anderson dianders@chromium.org
commit c884a0b27b4586e607431d86a1aa0bb4fb39169c upstream.
In btusb_mtk_setup(), we set `btmtk_data->isopkt_intf` to: usb_ifnum_to_if(data->udev, MTK_ISO_IFNUM)
That function can return NULL in some cases. Even when it returns NULL, though, we still go on to call btusb_mtk_claim_iso_intf().
As of commit e9087e828827 ("Bluetooth: btusb: mediatek: Add locks for usb_driver_claim_interface()"), calling btusb_mtk_claim_iso_intf() when `btmtk_data->isopkt_intf` is NULL will cause a crash because we'll end up passing a bad pointer to device_lock(). Prior to that commit we'd pass the NULL pointer directly to usb_driver_claim_interface() which would detect it and return an error, which was handled.
Resolve the crash in btusb_mtk_claim_iso_intf() by adding a NULL check at the start of the function. This makes the code handle a NULL `btmtk_data->isopkt_intf` the same way it did before the problematic commit (just with a slight change to the error message printed).
Reported-by: IncogCyberpunk incogcyberpunk@proton.me Closes: http://lore.kernel.org/r/a380d061-479e-4713-bddd-1d6571ca7e86@leemhuis.info Fixes: e9087e828827 ("Bluetooth: btusb: mediatek: Add locks for usb_driver_claim_interface()") Cc: stable@vger.kernel.org Tested-by: IncogCyberpunk incogcyberpunk@proton.me Signed-off-by: Douglas Anderson dianders@chromium.org Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/bluetooth/btusb.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -2721,6 +2721,11 @@ static void btusb_mtk_claim_iso_intf(str if (!btmtk_data) return;
+ if (!btmtk_data->isopkt_intf) { + bt_dev_err(data->hdev, "Can't claim NULL iso interface"); + return; + } + /* * The function usb_driver_claim_interface() is documented to need * locks held if it's not called from a probe routine. The code here