diff options
author | Geoffrey McRae <geoff@hostfission.com> | 2018-05-07 23:13:12 +1000 |
---|---|---|
committer | Gerd Hoffmann <kraxel@redhat.com> | 2018-05-15 11:31:33 +0200 |
commit | 7abe7eb29494b4e4a11ec99ae5623083409a2f1e (patch) | |
tree | aa098e5265093a38774a3c2d54a618140c128cf3 /hw | |
parent | 143c04c7e0639e53086519592ead15d2556bfbf2 (diff) |
ps2: Fix mouse stream corruption due to lost data
This fixes an issue by adding bounds checking to multi-byte packets
where the PS/2 mouse data stream may become corrupted due to data being
discarded when the PS/2 ringbuffer is full.
Interrupts for Multi-byte responses are postponed until the final byte
has been queued.
These changes fix a bug where windows guests drop the mouse device
entirely requring the guest to be restarted.
Signed-off-by: Geoffrey McRae <geoff@hostfission.com>
Message-Id: <20180507150310.2FEA0381924@moya.office.hostfission.com>
[ kraxel: codestyle fixes ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Diffstat (limited to 'hw')
-rw-r--r-- | hw/input/ps2.c | 124 |
1 files changed, 95 insertions, 29 deletions
diff --git a/hw/input/ps2.c b/hw/input/ps2.c index 4abc8cecdd..eeec6180d0 100644 --- a/hw/input/ps2.c +++ b/hw/input/ps2.c @@ -188,16 +188,64 @@ static void ps2_reset_queue(PS2State *s) q->count = 0; } -void ps2_queue(PS2State *s, int b) +void ps2_queue_noirq(PS2State *s, int b) { PS2Queue *q = &s->queue; - if (q->count >= PS2_QUEUE_SIZE - 1) + if (q->count == PS2_QUEUE_SIZE) { return; + } + q->data[q->wptr] = b; if (++q->wptr == PS2_QUEUE_SIZE) q->wptr = 0; q->count++; +} + +void ps2_raise_irq(PS2State *s) +{ + s->update_irq(s->update_arg, 1); +} + +void ps2_queue(PS2State *s, int b) +{ + ps2_queue_noirq(s, b); + s->update_irq(s->update_arg, 1); +} + +void ps2_queue_2(PS2State *s, int b1, int b2) +{ + if (PS2_QUEUE_SIZE - s->queue.count < 2) { + return; + } + + ps2_queue_noirq(s, b1); + ps2_queue_noirq(s, b2); + s->update_irq(s->update_arg, 1); +} + +void ps2_queue_3(PS2State *s, int b1, int b2, int b3) +{ + if (PS2_QUEUE_SIZE - s->queue.count < 3) { + return; + } + + ps2_queue_noirq(s, b1); + ps2_queue_noirq(s, b2); + ps2_queue_noirq(s, b3); + s->update_irq(s->update_arg, 1); +} + +void ps2_queue_4(PS2State *s, int b1, int b2, int b3, int b4) +{ + if (PS2_QUEUE_SIZE - s->queue.count < 4) { + return; + } + + ps2_queue_noirq(s, b1); + ps2_queue_noirq(s, b2); + ps2_queue_noirq(s, b3); + ps2_queue_noirq(s, b4); s->update_irq(s->update_arg, 1); } @@ -501,13 +549,17 @@ void ps2_write_keyboard(void *opaque, int val) ps2_queue(&s->common, KBD_REPLY_RESEND); break; case KBD_CMD_GET_ID: - ps2_queue(&s->common, KBD_REPLY_ACK); /* We emulate a MF2 AT keyboard here */ - ps2_queue(&s->common, KBD_REPLY_ID); if (s->translate) - ps2_queue(&s->common, 0x41); + ps2_queue_3(&s->common, + KBD_REPLY_ACK, + KBD_REPLY_ID, + 0x41); else - ps2_queue(&s->common, 0x83); + ps2_queue_3(&s->common, + KBD_REPLY_ACK, + KBD_REPLY_ID, + 0x83); break; case KBD_CMD_ECHO: ps2_queue(&s->common, KBD_CMD_ECHO); @@ -534,8 +586,9 @@ void ps2_write_keyboard(void *opaque, int val) break; case KBD_CMD_RESET: ps2_reset_keyboard(s); - ps2_queue(&s->common, KBD_REPLY_ACK); - ps2_queue(&s->common, KBD_REPLY_POR); + ps2_queue_2(&s->common, + KBD_REPLY_ACK, + KBD_REPLY_POR); break; default: ps2_queue(&s->common, KBD_REPLY_RESEND); @@ -544,8 +597,10 @@ void ps2_write_keyboard(void *opaque, int val) break; case KBD_CMD_SCANCODE: if (val == 0) { - ps2_queue(&s->common, KBD_REPLY_ACK); - ps2_put_keycode(s, s->scancode_set); + if (s->common.queue.count <= PS2_QUEUE_SIZE - 2) { + ps2_queue(&s->common, KBD_REPLY_ACK); + ps2_put_keycode(s, s->scancode_set); + } } else if (val >= 1 && val <= 3) { s->scancode_set = val; ps2_queue(&s->common, KBD_REPLY_ACK); @@ -577,11 +632,16 @@ void ps2_keyboard_set_translation(void *opaque, int mode) s->translate = mode; } -static void ps2_mouse_send_packet(PS2MouseState *s) +static int ps2_mouse_send_packet(PS2MouseState *s) { + const int needed = 3 + (s->mouse_type - 2); unsigned int b; int dx1, dy1, dz1; + if (PS2_QUEUE_SIZE - s->common.queue.count < needed) { + return 0; + } + dx1 = s->mouse_dx; dy1 = s->mouse_dy; dz1 = s->mouse_dz; @@ -595,9 +655,9 @@ static void ps2_mouse_send_packet(PS2MouseState *s) else if (dy1 < -127) dy1 = -127; b = 0x08 | ((dx1 < 0) << 4) | ((dy1 < 0) << 5) | (s->mouse_buttons & 0x07); - ps2_queue(&s->common, b); - ps2_queue(&s->common, dx1 & 0xff); - ps2_queue(&s->common, dy1 & 0xff); + ps2_queue_noirq(&s->common, b); + ps2_queue_noirq(&s->common, dx1 & 0xff); + ps2_queue_noirq(&s->common, dy1 & 0xff); /* extra byte for IMPS/2 or IMEX */ switch(s->mouse_type) { default: @@ -607,7 +667,7 @@ static void ps2_mouse_send_packet(PS2MouseState *s) dz1 = 127; else if (dz1 < -127) dz1 = -127; - ps2_queue(&s->common, dz1 & 0xff); + ps2_queue_noirq(&s->common, dz1 & 0xff); break; case 4: if (dz1 > 7) @@ -615,15 +675,19 @@ static void ps2_mouse_send_packet(PS2MouseState *s) else if (dz1 < -7) dz1 = -7; b = (dz1 & 0x0f) | ((s->mouse_buttons & 0x18) << 1); - ps2_queue(&s->common, b); + ps2_queue_noirq(&s->common, b); break; } + ps2_raise_irq(&s->common); + trace_ps2_mouse_send_packet(s, dx1, dy1, dz1, b); /* update deltas */ s->mouse_dx -= dx1; s->mouse_dy -= dy1; s->mouse_dz -= dz1; + + return 1; } static void ps2_mouse_event(DeviceState *dev, QemuConsole *src, @@ -687,10 +751,9 @@ static void ps2_mouse_sync(DeviceState *dev) qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER); } if (!(s->mouse_status & MOUSE_STATUS_REMOTE)) { - while (s->common.queue.count < PS2_QUEUE_SIZE - 4) { - /* if not remote, send event. Multiple events are sent if - too big deltas */ - ps2_mouse_send_packet(s); + /* if not remote, send event. Multiple events are sent if + too big deltas */ + while (ps2_mouse_send_packet(s)) { if (s->mouse_dx == 0 && s->mouse_dy == 0 && s->mouse_dz == 0) break; } @@ -749,8 +812,9 @@ void ps2_write_mouse(void *opaque, int val) ps2_queue(&s->common, AUX_ACK); break; case AUX_GET_TYPE: - ps2_queue(&s->common, AUX_ACK); - ps2_queue(&s->common, s->mouse_type); + ps2_queue_2(&s->common, + AUX_ACK, + s->mouse_type); break; case AUX_SET_RES: case AUX_SET_SAMPLE: @@ -758,10 +822,11 @@ void ps2_write_mouse(void *opaque, int val) ps2_queue(&s->common, AUX_ACK); break; case AUX_GET_SCALE: - ps2_queue(&s->common, AUX_ACK); - ps2_queue(&s->common, s->mouse_status); - ps2_queue(&s->common, s->mouse_resolution); - ps2_queue(&s->common, s->mouse_sample_rate); + ps2_queue_4(&s->common, + AUX_ACK, + s->mouse_status, + s->mouse_resolution, + s->mouse_sample_rate); break; case AUX_POLL: ps2_queue(&s->common, AUX_ACK); @@ -787,9 +852,10 @@ void ps2_write_mouse(void *opaque, int val) s->mouse_status = 0; s->mouse_type = 0; ps2_reset_queue(&s->common); - ps2_queue(&s->common, AUX_ACK); - ps2_queue(&s->common, 0xaa); - ps2_queue(&s->common, s->mouse_type); + ps2_queue_3(&s->common, + AUX_ACK, + 0xaa, + s->mouse_type); break; default: break; |