Hi Greg,
i get the following backtrace when booting the kernel with "console=ttyUSB0
console=tty0" while using a Keyspan USA-19HS the usb-to-serial converter
connected to a desktop machine:
<snip>
[ 43.782384] usbcore: registered new interface driver usbserial
[ 43.782444] drivers/usb/serial/usb-serial.c: USB Serial Driver core
[ 43.782543] drivers/usb/serial/usb-serial.c: USB Serial support registered for Keyspan - (without firmware)
[ 43.782652] drivers/usb/serial/usb-serial.c: USB Serial support registered for Keyspan 1 port adapter
[ 43.782759] drivers/usb/serial/usb-serial.c: USB Serial support registered for Keyspan 2 port adapter
[ 43.782866] drivers/usb/serial/usb-serial.c: USB Serial support registered for Keyspan 4 port adapter
[ 43.782980] usbcore: registered new interface driver keyspan
[ 43.783040] drivers/usb/serial/keyspan.c: v1.1.5:Keyspan USB to Serial Converter Driver
...
[ 124.816533] usb 3-1: new full speed USB device using uhci_hcd and address 2
[ 125.135811] usb 3-1: configuration #1 chosen from 2 choices
[ 125.140709] keyspan 3-1:1.0: Keyspan 1 port adapter converter detected
[ 125.141110] usb 3-1: Keyspan 1 port adapter converter now attached to ttyUSB0
[ 125.142446] BUG: unable to handle kernel NULL pointer dereference at virtual address 00000084
[ 125.142597] printing eip: c02654ca *pde = 00000000
[ 125.142764] BUG: using smp_processor_id() in preemptible [00000001] code: khubd/142
[ 125.142861] caller is die+0x59/0x1eb
[ 125.142930] [<c0105026>] show_trace_log_lvl+0x1a/0x2f
[ 125.143054] [<c0105a19>] show_trace+0x12/0x14
[ 125.143173] [<c0105b34>] dump_stack+0x16/0x18
[ 125.143293] [<c01e3c2f>] debug_smp_processor_id+0xa3/0xb8
[ 125.143429] [<c0105310>] die+0x59/0x1eb
[ 125.143546] [<c0119b07>] do_page_fault+0x42c/0x505
[ 125.143680] [<c02f8622>] error_code+0x72/0x78
[ 125.143802] [<c0262a50>] usb_console_setup+0x182/0x282
[ 125.143925] [<c0122676>] register_console+0xe9/0x21c
[ 125.144048] [<c02628a4>] usb_serial_console_init+0x31/0x33
[ 125.144171] [<c026190f>] usb_serial_probe+0xe3c/0xf55
[ 125.144293] [<c0253718>] usb_probe_interface+0xb6/0xe7
[ 125.144424] [<c0233b8c>] driver_probe_device+0xcb/0x14f
[ 125.144548] [<c0233c18>] __device_attach+0x8/0xa
[ 125.144678] [<c0232fb8>] bus_for_each_drv+0x3b/0x63
[ 125.144799] [<c0233ca9>] device_attach+0x70/0x85
[ 125.144919] [<c0232f2f>] bus_attach_device+0x29/0x77
[ 125.145040] [<c0232044>] device_add+0x302/0x514
[ 125.145160] [<c02521ff>] usb_set_configuration+0x418/0x46d
[ 125.145283] [<c0258b67>] generic_probe+0x53/0x94
[ 125.145403] [<c02534a9>] usb_probe_device+0x38/0x3e
[ 125.145523] [<c0233b8c>] driver_probe_device+0xcb/0x14f
[ 125.145656] [<c0233c18>] __device_attach+0x8/0xa
[ 125.145776] [<c0232fb8>] bus_for_each_drv+0x3b/0x63
[ 125.146675] [<c0233ca9>] device_attach+0x70/0x85
[ 125.146795] [<c0232f2f>] bus_attach_device+0x29/0x77
[ 125.146916] [<c0232044>] device_add+0x302/0x514
[ 125.147036] [<c024dc69>] usb_new_device+0x44/0x82
[ 125.147160] [<c024eeaa>] hub_thread+0x65a/0xa13
[ 125.147280] [<c0132daf>] kthread+0x3b/0x64
[ 125.147400] [<c0104c87>] kernel_thread_helper+0x7/0x10
[ 125.147521] =======================
[ 125.147600] Oops: 0000 [#1] PREEMPT SMP
[ 125.147805] Modules linked in: usbhid video output tg3 intel_agp uhci_hcd psmouse agpgart rtc evdev
[ 125.148403]
[ 125.148466] Pid: 142, comm: khubd Not tainted (2.6.24-rc1-521-g54866f0 #16)
[ 125.148546] BUG: using smp_processor_id() in preemptible [00000001] code: khubd/142
[ 125.148646] caller is __show_registers+0xad/0x1d8
[ 125.148717] [<c0105026>] show_trace_log_lvl+0x1a/0x2f
[ 125.148839] [<c0105a19>] show_trace+0x12/0x14
[ 125.148958] [<c0105b34>] dump_stack+0x16/0x18
[ 125.149077] [<c01e3c2f>] debug_smp_processor_id+0xa3/0xb8
[ 125.149201] [<c0102344>] __show_registers+0xad/0x1d8
[ 125.149321] [<c01050f7>] show_registers+0x19/0x1d9
[ 125.149440] [<c01053d6>] die+0x11f/0x1eb
[ 125.149557] [<c0119b07>] do_page_fault+0x42c/0x505
[ 125.149688] [<c02f8622>] error_code+0x72/0x78
[ 125.149808] [<c0262a50>] usb_console_setup+0x182/0x282
[ 125.149930] [<c0122676>] register_console+0xe9/0x21c
[ 125.150051] [<c02628a4>] usb_serial_console_init+0x31/0x33
[ 125.150175] [<c026190f>] usb_serial_probe+0xe3c/0xf55
[ 125.150296] [<c0253718>] usb_probe_interface+0xb6/0xe7
[ 125.150416] [<c0233b8c>] driver_probe_device+0xcb/0x14f
[ 125.150538] [<c0233c18>] __device_attach+0x8/0xa
[ 125.150669] [<c0232fb8>] bus_for_each_drv+0x3b/0x63
[ 125.150792] [<c0233ca9>] device_attach+0x70/0x85
[ 125.150913] [<c0232f2f>] bus_attach_device+0x29/0x77
[ 125.151036] [<c0232044>] device_add+0x302/0x514
[ 125.151156] [<c02521ff>] usb_set_configuration+0x418/0x46d
[ 125.151281] [<c0258b67>] generic_probe+0x53/0x94
[ 125.151402] [<c02534a9>] usb_probe_device+0x38/0x3e
[ 125.151523] [<c0233b8c>] driver_probe_device+0xcb/0x14f
[ 125.151658] [<c0233c18>] __device_attach+0x8/0xa
[ 125.151780] [<c0232fb8>] bus_for_each_drv+0x3b/0x63
[ 125.151902] [<c0233ca9>] device_attach+0x70/0x85
[ 125.152023] [<c0232f2f>] bus_attach_device+0x29/0x77
[ 125.152146] [<c0232044>] device_add+0x302/0x514
[ 125.152266] [<c024dc69>] usb_new_device+0x44/0x82
[ 125.152388] [<c024eeaa>] hub_thread+0x65a/0xa13
[ 125.152508] [<c0132daf>] kthread+0x3b/0x64
[ 125.152633] [<c0104c87>] kernel_thread_helper+0x7/0x10
[ 125.152754] =======================
[ 125.152822] EIP: 0060:[<c02654ca>] EFLAGS: 00010246 CPU: 0
[ 125.152901] EIP is at keyspan_open+0x11c/0x19d
[ 125.152971] EAX: 00000000 EBX: c19e7c00 ECX: c19e7c00 EDX: c19e7c00
[ 125.153047] ESI: c1bd3e00 EDI: 00000002 EBP: c1886b54 ESP: c1886b1c
[ 125.153123] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[ 125.153197] Process khubd (pid: 142, ti=c1886000 task=c1843080 task.ti=c1886000)
[ 125.153274] Stack: 00000246 22222222 22222222 22222222 22222222 c03eeb40 c19e7c00 0000006e
[ 125.153775] c1aeab40 c030fcec c02f72b5 c19e7c00 0000006e c03eed18 c1886bb0 c0262a50
[ 125.154264] c02316d6 c1886b68 c0232e33 c1aeab40 c1886b78 c01dd877 00000cbd c1886b80
[ 125.154762] Call Trace:
[ 125.154875] [<c0105026>] show_trace_log_lvl+0x1a/0x2f
[ 125.154995] [<c01050d6>] show_stack_log_lvl+0x9b/0xa3
[ 125.155115] [<c0105182>] show_registers+0xa4/0x1d9
[ 125.155235] [<c01053d6>] die+0x11f/0x1eb
[ 125.155352] [<c0119b07>] do_page_fault+0x42c/0x505
[ 125.155472] [<c02f8622>] error_code+0x72/0x78
[ 125.155654] [<c0262a50>] usb_console_setup+0x182/0x282
[ 125.155774] [<c0122676>] register_console+0xe9/0x21c
[ 125.155893] [<c02628a4>] usb_serial_console_init+0x31/0x33
[ 125.156013] [<c026190f>] usb_serial_probe+0xe3c/0xf55
[ 125.156131] [<c0253718>] usb_probe_interface+0xb6/0xe7
[ 125.156251] [<c0233b8c>] driver_probe_device+0xcb/0x14f
[ 125.156370] [<c0233c18>] __device_attach+0x8/0xa
[ 125.156488] [<c0232fb8>] bus_for_each_drv+0x3b/0x63
[ 125.156616] [<c0233ca9>] device_attach+0x70/0x85
[ 125.156734] [<c0232f2f>] bus_attach_device+0x29/0x77
[ 125.156852] [<c0232044>] device_add+0x302/0x514
[ 125.156969] [<c02521ff>] usb_set_configuration+0x418/0x46d
[ 125.157089] [<c0258b67>] generic_probe+0x53/0x94
[ 125.157207] [<c02534a9>] usb_probe_device+0x38/0x3e
[ 125.157325] [<c0233b8c>] driver_probe_device+0xcb/0x14f
[ 125.157445] [<c0233c18>] __device_attach+0x8/0xa
[ 125.157562] [<c0232fb8>] bus_for_each_drv+0x3b/0x63
[ 125.157689] [<c0233ca9>] device_attach+0x70/0x85
[ 125.157806] [<c0232f2f>] bus_attach_device+0x29/0x77
[ 125.157925] [<c0232044>] device_add+0x302/0x514
[ 125.158041] [<c024dc69>] usb_new_device+0x44/0x82
[ 125.158160] [<c024eeaa>] hub_thread+0x65a/0xa13
[ 125.158277] [<c0132daf>] kthread+0x3b/0x64
[ 125.158393] [<c0104c87>] kernel_thread_helper+0x7/0x10
[ 125.158512] =======================
[ 125.158577] Code: 74 08 8b 4d e8 8b 01 89 42 28 8b 96 98 00 00 00 85 d2 74 08 8b 5d e8 8b 03 89 42 28 8b 55 e0 8b 4d e0 8b 5d e0 8b 42 04 8a 49 48 <8b> 90 84 00 00 00 8b 7a 08 88 4d f3 8b 13 8a 52 0c 88 55 e7 e8
[ 50.035324] EIP: [<c02654ca>] keyspan_open+0x11c/0x19d SS:ESP 0068:c1886b1c
</snip>
and this happens, imho, because in usb_console_setup(), port->tty is set to NULL
prior to calling serial->type->open() which is keyspan_open() in this case. In
keyspan_open(), otoh, some premature terminal config is done for the purposes of
the setup message by deref'ing, among others, port->tty->termios->c_flag, which,
as we saw before :) is NULL and BAM! The patch below is against current git
(v2.6.24-rc1-573-g74521c2).
---
From: Borislav Petkov <[email protected]>
Remove redundant code leading to NULL ptr deref and let terminal config settings
take place in the proper initialization path in usb_console_setup().
Signed-off-by: Borislav Petkov <[email protected]>
--
drivers/usb/serial/keyspan.c | 38 ++++++--------------------------------
1 files changed, 6 insertions(+), 32 deletions(-)
diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c
index 6bfdba6..1f7ab15 100644
--- a/drivers/usb/serial/keyspan.c
+++ b/drivers/usb/serial/keyspan.c
@@ -1215,20 +1215,18 @@ static int keyspan_chars_in_buffer (struct usb_serial_port *port)
static int keyspan_open (struct usb_serial_port *port, struct file *filp)
{
- struct keyspan_port_private *p_priv;
- struct keyspan_serial_private *s_priv;
- struct usb_serial *serial = port->serial;
+ struct keyspan_port_private *p_priv;
+ struct keyspan_serial_private *s_priv;
+ struct usb_serial *serial = port->serial;
const struct keyspan_device_details *d_details;
int i, err;
- int baud_rate, device_port;
struct urb *urb;
- unsigned int cflag;
s_priv = usb_get_serial_data(serial);
p_priv = usb_get_serial_port_data(port);
d_details = p_priv->device_details;
-
- dbg("%s - port%d.", __FUNCTION__, port->number);
+
+ dbg("%s - port%d.", __FUNCTION__, port->number);
/* Set some sane defaults */
p_priv->rts_state = 1;
@@ -1249,7 +1247,7 @@ static int keyspan_open (struct usb_serial_port *port, struct file *filp)
urb->dev = serial->dev;
/* make sure endpoint data toggle is synchronized with the device */
-
+
usb_clear_halt(urb->dev, urb->pipe);
if ((err = usb_submit_urb(urb, GFP_KERNEL)) != 0) {
@@ -1265,30 +1263,6 @@ static int keyspan_open (struct usb_serial_port *port, struct file *filp)
/* usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe), usb_pipeout(urb->pipe), 0); */
}
- /* get the terminal config for the setup message now so we don't
- * need to send 2 of them */
-
- cflag = port->tty->termios->c_cflag;
- device_port = port->number - port->serial->minor;
-
- /* Baud rate calculation takes baud rate as an integer
- so other rates can be generated if desired. */
- baud_rate = tty_get_baud_rate(port->tty);
- /* If no match or invalid, leave as default */
- if (baud_rate >= 0
- && d_details->calculate_baud_rate(baud_rate, d_details->baudclk,
- NULL, NULL, NULL, device_port) == KEYSPAN_BAUD_RATE_OK) {
- p_priv->baud = baud_rate;
- }
-
- /* set CTS/RTS handshake etc. */
- p_priv->cflag = cflag;
- p_priv->flow_control = (cflag & CRTSCTS)? flow_cts: flow_none;
-
- keyspan_send_setup(port, 1);
- //mdelay(100);
- //keyspan_set_termios(port, NULL);
-
return (0);
}
