This is a note to let you know that I've just added the patch titled bluetooth: Add cmd validity checks at the start of hci_sock_ioctl() to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bluetooth-add-cmd-validity-checks-at-the-start-of-hci_sock_ioctl.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 000c2fa2c144c499c881a101819cf1936a1f7cf2 Mon Sep 17 00:00:00 2001 From: Ruihan Li <lrh2000@xxxxxxxxxx> Date: Sun, 16 Apr 2023 16:02:51 +0800 Subject: bluetooth: Add cmd validity checks at the start of hci_sock_ioctl() From: Ruihan Li <lrh2000@xxxxxxxxxx> commit 000c2fa2c144c499c881a101819cf1936a1f7cf2 upstream. Previously, channel open messages were always sent to monitors on the first ioctl() call for unbound HCI sockets, even if the command and arguments were completely invalid. This can leave an exploitable hole with the abuse of invalid ioctl calls. This commit hardens the ioctl processing logic by first checking if the command is valid, and immediately returning with an ENOIOCTLCMD error code if it is not. This ensures that ioctl calls with invalid commands are free of side effects, and increases the difficulty of further exploitation by forcing exploitation to find a way to pass a valid command first. Signed-off-by: Ruihan Li <lrh2000@xxxxxxxxxx> Co-developed-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Dragos-Marian Panait <dragos.panait@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/bluetooth/hci_sock.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) --- a/net/bluetooth/hci_sock.c +++ b/net/bluetooth/hci_sock.c @@ -973,6 +973,34 @@ static int hci_sock_ioctl(struct socket BT_DBG("cmd %x arg %lx", cmd, arg); + /* Make sure the cmd is valid before doing anything */ + switch (cmd) { + case HCIGETDEVLIST: + case HCIGETDEVINFO: + case HCIGETCONNLIST: + case HCIDEVUP: + case HCIDEVDOWN: + case HCIDEVRESET: + case HCIDEVRESTAT: + case HCISETSCAN: + case HCISETAUTH: + case HCISETENCRYPT: + case HCISETPTYPE: + case HCISETLINKPOL: + case HCISETLINKMODE: + case HCISETACLMTU: + case HCISETSCOMTU: + case HCIINQUIRY: + case HCISETRAW: + case HCIGETCONNINFO: + case HCIGETAUTHINFO: + case HCIBLOCKADDR: + case HCIUNBLOCKADDR: + break; + default: + return -ENOIOCTLCMD; + } + lock_sock(sk); if (hci_pi(sk)->channel != HCI_CHANNEL_RAW) { Patches currently in stable-queue which might be from lrh2000@xxxxxxxxxx are queue-5.4/bluetooth-add-cmd-validity-checks-at-the-start-of-hci_sock_ioctl.patch