diff options
| author | Guenter Roeck <linux@roeck-us.net> | 2019-08-02 09:03:42 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-02 18:18:10 +0200 |
| commit | 88d02c9ba2e83fc22d37ccb1f11c62ea6fc9ae50 (patch) | |
| tree | ddee6ddb9eb7ec7c0b5e78941f796f5fa4946e10 /drivers/usb/typec | |
| parent | cb53c517285f8d2548d11422173ca8ec7b9c8f44 (diff) | |
usb: typec: tcpm: Ignore unsupported/unknown alternate mode requests
TCPM may receive PD messages associated with unknown or unsupported
alternate modes. If that happens, calls to typec_match_altmode()
will return NULL. The tcpm code does not currently take this into
account. This results in crashes.
Unable to handle kernel NULL pointer dereference at virtual address 000001f0
pgd = 41dad9a1
[000001f0] *pgd=00000000
Internal error: Oops: 5 [#1] THUMB2
Modules linked in: tcpci tcpm
CPU: 0 PID: 2338 Comm: kworker/u2:0 Not tainted 5.1.18-sama5-armv7-r2 #6
Hardware name: Atmel SAMA5
Workqueue: 2-0050 tcpm_pd_rx_handler [tcpm]
PC is at typec_altmode_attention+0x0/0x14
LR is at tcpm_pd_rx_handler+0xa3b/0xda0 [tcpm]
...
[<c03fbee8>] (typec_altmode_attention) from [<bf8030fb>]
(tcpm_pd_rx_handler+0xa3b/0xda0 [tcpm])
[<bf8030fb>] (tcpm_pd_rx_handler [tcpm]) from [<c012082b>]
(process_one_work+0x123/0x2a8)
[<c012082b>] (process_one_work) from [<c0120a6d>]
(worker_thread+0xbd/0x3b0)
[<c0120a6d>] (worker_thread) from [<c012431f>] (kthread+0xcf/0xf4)
[<c012431f>] (kthread) from [<c01010f9>] (ret_from_fork+0x11/0x38)
Ignore PD messages if the associated alternate mode is not supported.
Fixes: e9576fe8e605c ("usb: typec: tcpm: Support for Alternate Modes")
Cc: stable <stable@vger.kernel.org>
Reported-by: Douglas Gilbert <dgilbert@interlog.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1564761822-13984-1-git-send-email-linux@roeck-us.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/typec')
| -rw-r--r-- | drivers/usb/typec/tcpm/tcpm.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index ab6456622120..15abe1d9958f 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -1109,7 +1109,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt, break; case CMD_ATTENTION: /* Attention command does not have response */ - typec_altmode_attention(adev, p[1]); + if (adev) + typec_altmode_attention(adev, p[1]); return 0; default: break; @@ -1161,20 +1162,26 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt, } break; case CMD_ENTER_MODE: - typec_altmode_update_active(pdev, true); - - if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) { - response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE); - response[0] |= VDO_OPOS(adev->mode); - return 1; + if (adev && pdev) { + typec_altmode_update_active(pdev, true); + + if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) { + response[0] = VDO(adev->svid, 1, + CMD_EXIT_MODE); + response[0] |= VDO_OPOS(adev->mode); + return 1; + } } return 0; case CMD_EXIT_MODE: - typec_altmode_update_active(pdev, false); + if (adev && pdev) { + typec_altmode_update_active(pdev, false); - /* Back to USB Operation */ - WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, - NULL)); + /* Back to USB Operation */ + WARN_ON(typec_altmode_notify(adev, + TYPEC_STATE_USB, + NULL)); + } break; default: break; @@ -1184,8 +1191,10 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt, switch (cmd) { case CMD_ENTER_MODE: /* Back to USB Operation */ - WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, - NULL)); + if (adev) + WARN_ON(typec_altmode_notify(adev, + TYPEC_STATE_USB, + NULL)); break; default: break; @@ -1196,7 +1205,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt, } /* Informing the alternate mode drivers about everything */ - typec_altmode_vdm(adev, p[0], &p[1], cnt); + if (adev) + typec_altmode_vdm(adev, p[0], &p[1], cnt); return rlen; } |