Message ID | 20250502-b4-new-fix-pd-rx-count-v1-1-e5711ed09b3d@google.com |
---|---|
State | New |
Headers | show |
Series | usb: typec: tcpm/tcpci_maxim: Fix bounds check in process_rx() | expand |
On Fri, May 02, 2025 at 04:57:03PM -0700, Amit Sunil Dhamne via B4 Relay wrote: > From: Amit Sunil Dhamne <amitsd@google.com> > > Register read of TCPC_RX_BYTE_CNT returns the total size consisting of: > > PD message (pending read) size + 1 Byte for Frame Type (SOP*) > > This is validated against the max PD message (`struct pd_message`) size > without accounting for the extra byte for the frame type. Note that the > struct pd_message does not contain a field for the frame_type. This > results in false negatives when the "PD message (pending read)" is equal > to the max PD message size. > > Fixes: 6f413b559f86 ("usb: typec: tcpci_maxim: Chip level TCPC driver") > Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> > Reviewed-by: Kyle Tso <kyletso@google.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > drivers/usb/typec/tcpm/tcpci_maxim_core.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/typec/tcpm/tcpci_maxim_core.c b/drivers/usb/typec/tcpm/tcpci_maxim_core.c > index fd1b80593367641a6f997da2fb97a2b7238f6982..648311f5e3cf135f23b5cc0668001d2f177b9edd 100644 > --- a/drivers/usb/typec/tcpm/tcpci_maxim_core.c > +++ b/drivers/usb/typec/tcpm/tcpci_maxim_core.c > @@ -166,7 +166,8 @@ static void process_rx(struct max_tcpci_chip *chip, u16 status) > return; > } > > - if (count > sizeof(struct pd_message) || count + 1 > TCPC_RECEIVE_BUFFER_LEN) { > + if (count > sizeof(struct pd_message) + 1 || > + count + 1 > TCPC_RECEIVE_BUFFER_LEN) { > dev_err(chip->dev, "Invalid TCPC_RX_BYTE_CNT %d\n", count); > return; > } > > --- > base-commit: ebd297a2affadb6f6f4d2e5d975c1eda18ac762d > change-id: 20250421-b4-new-fix-pd-rx-count-79297ba619b7 > > Best regards, > -- > Amit Sunil Dhamne <amitsd@google.com> >
diff --git a/drivers/usb/typec/tcpm/tcpci_maxim_core.c b/drivers/usb/typec/tcpm/tcpci_maxim_core.c index fd1b80593367641a6f997da2fb97a2b7238f6982..648311f5e3cf135f23b5cc0668001d2f177b9edd 100644 --- a/drivers/usb/typec/tcpm/tcpci_maxim_core.c +++ b/drivers/usb/typec/tcpm/tcpci_maxim_core.c @@ -166,7 +166,8 @@ static void process_rx(struct max_tcpci_chip *chip, u16 status) return; } - if (count > sizeof(struct pd_message) || count + 1 > TCPC_RECEIVE_BUFFER_LEN) { + if (count > sizeof(struct pd_message) + 1 || + count + 1 > TCPC_RECEIVE_BUFFER_LEN) { dev_err(chip->dev, "Invalid TCPC_RX_BYTE_CNT %d\n", count); return; }