diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-05-13 17:52:54 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-05-19 12:25:59 +0200 |
| commit | 167dd8d12226587ee554f520aed0256b7769cd5d (patch) | |
| tree | fa485b9510bdd37dba21238f58e46ebb9a7837de | |
| parent | 3389c149c68c3fea61910ad5d34f7bf3bff44e32 (diff) | |
usb: typec: ucsi: displayport: NAK DP_CMD_CONFIGURE without a payload VDO
ucsi_displayport_vdm() handles a DP_CMD_CONFIGURE by copying the first
payload VDO from data[], but unlike the equivalent handler in
altmodes/displayport.c it does not check that count covers a VDO beyond
the header. A header-only Configure VDM (count == 1) would read one u32
past the caller's array.
In the normal UCSI path the caller controls count, so this is hardening
for non-standard delivery paths. NAK and bail when no configuration VDO
is present, matching the generic DP altmode driver's existing guard.
Assisted-by: gkh_clanker_t1000
Cc: Pooja Katiyar <pooja.katiyar@intel.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: stable <stable@kernel.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/2026051351-vividly-flattered-eb3d@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/typec/ucsi/displayport.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/usb/typec/ucsi/displayport.c b/drivers/usb/typec/ucsi/displayport.c index 8aae80b457d7..67a0991a7b76 100644 --- a/drivers/usb/typec/ucsi/displayport.c +++ b/drivers/usb/typec/ucsi/displayport.c @@ -240,6 +240,10 @@ static int ucsi_displayport_vdm(struct typec_altmode *alt, dp->header |= VDO_CMDT(CMDT_RSP_ACK); break; case DP_CMD_CONFIGURE: + if (count < 2) { + dp->header |= VDO_CMDT(CMDT_RSP_NAK); + break; + } dp->data.conf = *data; if (ucsi_displayport_configure(dp)) { dp->header |= VDO_CMDT(CMDT_RSP_NAK); |