summaryrefslogtreecommitdiff
path: root/drivers/usb
diff options
context:
space:
mode:
authorJiri Slaby <jslaby@suse.cz>2011-02-15 15:55:07 +0100
committerGreg Kroah-Hartman <gregkh@suse.de>2011-02-17 10:30:25 -0800
commit38237fd2be9421c104f84cc35665097bdce89013 (patch)
tree5f8a8906662f9d0a398db53332d8f2204878b0c6 /drivers/usb
parent637d11bfb814637ec7b81e878db3ffea6408a89a (diff)
USB: serial/usb_wwan, fix tty NULL dereference
tty_port_tty_get may return without any problems NULL. Handle this case and do not oops in usb_wwan_indat_callback by dereferencing it. The oops: Unable to handle kernel paging request for data at address 0x000000d8 Faulting instruction address: 0xc0175b3c Oops: Kernel access of bad area, sig: 11 [#1] PowerPC 40x Platform last sysfs file: /sys/devices/pci0000:00/0000:00:00.0/0000:01:00.0/0000:02:09.2/usb1/idVendor Modules linked in: NIP: c0175b3c LR: c0175e7c CTR: c0215c90 REGS: c77f7d50 TRAP: 0300 Not tainted (2.6.37-rc5) MSR: 00021030 <ME,CE,IR,DR> CR: 88482028 XER: 2000005f DEAR: 000000d8, ESR: 00000000 TASK = c7141b90[1149] 'wvdial' THREAD: c2750000 GPR00: 00021030 c77f7e00 c7141b90 00000000 0000000e 00000000 0000000e c0410680 GPR08: c683db00 00000000 00000001 c03c81f8 88482028 10073ef4 ffffffb9 ffffff94 GPR16: 00000000 fde036c0 00200200 00100100 00000001 ffffff8d c34fabcc 00000000 GPR24: c71120d4 00000000 00000000 0000000e 00021030 00000000 00000000 0000000e NIP [c0175b3c] tty_buffer_request_room+0x2c/0x194 LR [c0175e7c] tty_insert_flip_string_fixed_flag+0x3c/0xb0 Call Trace: [c77f7e00] [00000003] 0x3 (unreliable) [c77f7e30] [c0175e7c] tty_insert_flip_string_fixed_flag+0x3c/0xb0 [c77f7e60] [c0215df4] usb_wwan_indat_callback+0x164/0x170 ... References: https://bugzilla.kernel.org/show_bug.cgi?id=24582 Cc: Amit Shah <amitshah@gmx.net> Cc: baoyb <baoyb@avit.org.cn> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/serial/usb_wwan.c15
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/usb/serial/usb_wwan.c b/drivers/usb/serial/usb_wwan.c
index b004b2a485c3..9c014e2ecd68 100644
--- a/drivers/usb/serial/usb_wwan.c
+++ b/drivers/usb/serial/usb_wwan.c
@@ -295,12 +295,15 @@ static void usb_wwan_indat_callback(struct urb *urb)
__func__, status, endpoint);
} else {
tty = tty_port_tty_get(&port->port);
- if (urb->actual_length) {
- tty_insert_flip_string(tty, data, urb->actual_length);
- tty_flip_buffer_push(tty);
- } else
- dbg("%s: empty read urb received", __func__);
- tty_kref_put(tty);
+ if (tty) {
+ if (urb->actual_length) {
+ tty_insert_flip_string(tty, data,
+ urb->actual_length);
+ tty_flip_buffer_push(tty);
+ } else
+ dbg("%s: empty read urb received", __func__);
+ tty_kref_put(tty);
+ }
/* Resubmit urb so we continue receiving */
if (status != -ESHUTDOWN) {