6.12-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Torokhov dmitry.torokhov@gmail.com
[ Upstream commit 08bd5b7c9a2401faabdaa1472d45c7de0755fd7e ]
When enabling a pass-through port an interrupt might come before psmouse driver binds to the pass-through port. However synaptics sub-driver tries to access psmouse instance presumably associated with the pass-through port to figure out if only 1 byte of response or entire protocol packet needs to be forwarded to the pass-through port and may crash if psmouse instance has not been attached to the port yet.
Fix the crash by introducing open() and close() methods for the port and check if the port is open before trying to access psmouse instance. Because psmouse calls serio_open() only after attaching psmouse instance to serio port instance this prevents the potential crash.
Reported-by: Takashi Iwai tiwai@suse.de Fixes: 100e16959c3c ("Input: libps2 - attach ps2dev instances as serio port's drvdata") Link: https://bugzilla.suse.com/show_bug.cgi?id=1219522 Cc: stable@vger.kernel.org Reviewed-by: Takashi Iwai tiwai@suse.de Link: https://lore.kernel.org/r/Z4qSHORvPn7EU2j1@google.com Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/input/mouse/synaptics.c | 56 ++++++++++++++++++++++++--------- drivers/input/mouse/synaptics.h | 1 + 2 files changed, 43 insertions(+), 14 deletions(-)
diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c index 380aa1614442f..3d1459b551bb2 100644 --- a/drivers/input/mouse/synaptics.c +++ b/drivers/input/mouse/synaptics.c @@ -667,23 +667,50 @@ static void synaptics_pt_stop(struct serio *serio) serio_continue_rx(parent->ps2dev.serio); }
+static int synaptics_pt_open(struct serio *serio) +{ + struct psmouse *parent = psmouse_from_serio(serio->parent); + struct synaptics_data *priv = parent->private; + + guard(serio_pause_rx)(parent->ps2dev.serio); + priv->pt_port_open = true; + + return 0; +} + +static void synaptics_pt_close(struct serio *serio) +{ + struct psmouse *parent = psmouse_from_serio(serio->parent); + struct synaptics_data *priv = parent->private; + + guard(serio_pause_rx)(parent->ps2dev.serio); + priv->pt_port_open = false; +} + static int synaptics_is_pt_packet(u8 *buf) { return (buf[0] & 0xFC) == 0x84 && (buf[3] & 0xCC) == 0xC4; }
-static void synaptics_pass_pt_packet(struct serio *ptport, u8 *packet) +static void synaptics_pass_pt_packet(struct synaptics_data *priv, u8 *packet) { - struct psmouse *child = psmouse_from_serio(ptport); + struct serio *ptport;
- if (child && child->state == PSMOUSE_ACTIVATED) { - serio_interrupt(ptport, packet[1], 0); - serio_interrupt(ptport, packet[4], 0); - serio_interrupt(ptport, packet[5], 0); - if (child->pktsize == 4) - serio_interrupt(ptport, packet[2], 0); - } else { - serio_interrupt(ptport, packet[1], 0); + ptport = priv->pt_port; + if (!ptport) + return; + + serio_interrupt(ptport, packet[1], 0); + + if (priv->pt_port_open) { + struct psmouse *child = psmouse_from_serio(ptport); + + if (child->state == PSMOUSE_ACTIVATED) { + serio_interrupt(ptport, packet[4], 0); + serio_interrupt(ptport, packet[5], 0); + if (child->pktsize == 4) + serio_interrupt(ptport, packet[2], 0); + } } }
@@ -722,6 +749,8 @@ static void synaptics_pt_create(struct psmouse *psmouse) serio->write = synaptics_pt_write; serio->start = synaptics_pt_start; serio->stop = synaptics_pt_stop; + serio->open = synaptics_pt_open; + serio->close = synaptics_pt_close; serio->parent = psmouse->ps2dev.serio;
psmouse->pt_activate = synaptics_pt_activate; @@ -1218,11 +1247,10 @@ static psmouse_ret_t synaptics_process_byte(struct psmouse *psmouse)
if (SYN_CAP_PASS_THROUGH(priv->info.capabilities) && synaptics_is_pt_packet(psmouse->packet)) { - if (priv->pt_port) - synaptics_pass_pt_packet(priv->pt_port, - psmouse->packet); - } else + synaptics_pass_pt_packet(priv, psmouse->packet); + } else { synaptics_process_packet(psmouse); + }
return PSMOUSE_FULL_PACKET; } diff --git a/drivers/input/mouse/synaptics.h b/drivers/input/mouse/synaptics.h index 08533d1b1b16f..4b34f13b9f761 100644 --- a/drivers/input/mouse/synaptics.h +++ b/drivers/input/mouse/synaptics.h @@ -188,6 +188,7 @@ struct synaptics_data { bool disable_gesture; /* disable gestures */
struct serio *pt_port; /* Pass-through serio port */ + bool pt_port_open;
/* * Last received Advanced Gesture Mode (AGM) packet. An AGM packet