From: Raphael Pinsonneault-Thibeault <rpthibeault@gmail.com> stable inclusion from stable-v6.6.117 commit 779f83a91d4f1bf5ddfeaf528420cbb6dbf03fa8 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11326 CVE: CVE-2025-40301 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- [ Upstream commit 5c5f1f64681cc889d9b13e4a61285e9e029d6ab5 ] In hci_cmd_complete_evt(), if the command complete event has an unknown opcode, we assume the first byte of the remaining skb->data contains the return status. However, parameter data has previously been pulled in hci_event_func(), which may leave the skb empty. If so, using skb->data[0] for the return status uses un-init memory. The fix is to check skb->len before using skb->data. Reported-by: syzbot+a9a4bedfca6aa9d7fa24@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=a9a4bedfca6aa9d7fa24 Tested-by: syzbot+a9a4bedfca6aa9d7fa24@syzkaller.appspotmail.com Fixes: afcb3369f46ed ("Bluetooth: hci_event: Fix vendor (unknown) opcode status handling") Signed-off-by: Raphael Pinsonneault-Thibeault <rpthibeault@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zhang Hongtao <zhanghongtao35@huawei.com> --- net/bluetooth/hci_event.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index ee9cd3d34c2d..cc95c9236921 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4245,6 +4245,13 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, void *data, } if (i == ARRAY_SIZE(hci_cc_table)) { + if (!skb->len) { + bt_dev_err(hdev, "Unexpected cc 0x%4.4x with no status", + *opcode); + *status = HCI_ERROR_UNSPECIFIED; + return; + } + /* Unknown opcode, assume byte 0 contains the status, so * that e.g. __hci_cmd_sync() properly returns errors * for vendor specific commands send by HCI drivers. -- 2.34.1