| Message ID | TYUPR06MB6217DAA095A9863D4B58D57CD23B2@TYUPR06MB6217.apcprd06.prod.outlook.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] usb: gadget: u_serial: Disable ep before setting port to null to fix the crash caused by port being null | expand |
On Mon, Dec 16, 2024 at 12:31:45PM +0000, 胡连勤 wrote: > From: Lianqin Hu <hulianqin@vivo.com> > > Considering that in some extreme cases, when performing the > unbinding operation, gserial_disconnect has cleared gser->ioport, > which triggers gadget reconfiguration, and then calls gs_read_complete, > resulting in access to a null pointer. Therefore, ep is disabled before > gserial_disconnect sets port to null to prevent this from happening. > > Call trace: > gs_read_complete+0x58/0x240 > usb_gadget_giveback_request+0x40/0x160 > dwc3_remove_requests+0x170/0x484 > dwc3_ep0_out_start+0xb0/0x1d4 > __dwc3_gadget_start+0x25c/0x720 > kretprobe_trampoline.cfi_jt+0x0/0x8 > kretprobe_trampoline.cfi_jt+0x0/0x8 > udc_bind_to_driver+0x1d8/0x300 > usb_gadget_probe_driver+0xa8/0x1dc > gadget_dev_desc_UDC_store+0x13c/0x188 > configfs_write_iter+0x160/0x1f4 > vfs_write+0x2d0/0x40c > ksys_write+0x7c/0xf0 > __arm64_sys_write+0x20/0x30 > invoke_syscall+0x60/0x150 > el0_svc_common+0x8c/0xf8 > do_el0_svc+0x28/0xa0 > el0_svc+0x24/0x84 > > Fixes: c1dca562be8a ("usb gadget: split out serial core") > Cc: stable@vger.kernel.org > > Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Signed-off-by: Lianqin Hu <hulianqin@vivo.com> > > v2: > - Remove some address information from patch descriptions > - Link to v1: https://lore.kernel.org/all/TYUPR06MB621763AB815989161F4033AFD2762@TYUPR06MB6217.apcprd06.prod.outlook.com/ > - Link to suggestions: https://lore.kernel.org/all/TYUPR06MB6217DE28012FFEC5E808DD64D2962@TYUPR06MB6217.apcprd06.prod.outlook.com/ The "v2:" needs to go below the --- line, what happened to that? And no need to have a blank line after the cc: stable, right? Did you run checkpatch.pl on this? thanks, greg k-h
Hello Linux kernel expert: > > From: Lianqin Hu <hulianqin@vivo.com> > > > > Considering that in some extreme cases, when performing the unbinding > > operation, gserial_disconnect has cleared gser->ioport, which triggers > > gadget reconfiguration, and then calls gs_read_complete, resulting in > > access to a null pointer. Therefore, ep is disabled before > > gserial_disconnect sets port to null to prevent this from happening. > > > > Call trace: > > gs_read_complete+0x58/0x240 > > usb_gadget_giveback_request+0x40/0x160 > > dwc3_remove_requests+0x170/0x484 > > dwc3_ep0_out_start+0xb0/0x1d4 > > __dwc3_gadget_start+0x25c/0x720 > > kretprobe_trampoline.cfi_jt+0x0/0x8 > > kretprobe_trampoline.cfi_jt+0x0/0x8 > > udc_bind_to_driver+0x1d8/0x300 > > usb_gadget_probe_driver+0xa8/0x1dc > > gadget_dev_desc_UDC_store+0x13c/0x188 > > configfs_write_iter+0x160/0x1f4 > > vfs_write+0x2d0/0x40c > > ksys_write+0x7c/0xf0 > > __arm64_sys_write+0x20/0x30 > > invoke_syscall+0x60/0x150 > > el0_svc_common+0x8c/0xf8 > > do_el0_svc+0x28/0xa0 > > el0_svc+0x24/0x84 > > > > Fixes: c1dca562be8a ("usb gadget: split out serial core") > > Cc: stable@vger.kernel.org > > > > Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > Signed-off-by: Lianqin Hu <hulianqin@vivo.com> > > > > v2: > > - Remove some address information from patch descriptions > > - Link to v1: > > https://apc01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore > > .kernel.org%2Fall%2FTYUPR06MB621763AB815989161F4033AFD2762%40TY > UPR06MB > > - Link to suggestions: > > https://apc01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore > > .kernel.org%2Fall%2FTYUPR06MB6217DE28012FFEC5E808DD64D2962%40TY > UPR06MB > > The "v2:" needs to go below the --- line, what happened to that? OK, I'll modify it. > And no need to have a blank line after the cc: stable, right? Did you run > checkpatch.pl on this? Sorry, I didn't check it carefully enough. I will modify it and send a new patch. Run checkpatch.pl before sending the patch: root@vivo-600-G6:~/linux_kernel/linux# ./scripts/checkpatch.pl 0001-usb-gadget-u_serial-Disable-ep-before-setting-port-t.patch total: 0 errors, 0 warnings, 20 lines checked Thanks
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index 53d9fc41acc5..bc143a86c2dd 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -1420,6 +1420,10 @@ void gserial_disconnect(struct gserial *gser) /* REVISIT as above: how best to track this? */ port->port_line_coding = gser->port_line_coding; + /* disable endpoints, aborting down any active I/O */ + usb_ep_disable(gser->out); + usb_ep_disable(gser->in); + port->port_usb = NULL; gser->ioport = NULL; if (port->port.count > 0) { @@ -1431,10 +1435,6 @@ void gserial_disconnect(struct gserial *gser) spin_unlock(&port->port_lock); spin_unlock_irqrestore(&serial_port_lock, flags); - /* disable endpoints, aborting down any active I/O */ - usb_ep_disable(gser->out); - usb_ep_disable(gser->in); - /* finally, free any unused/unusable I/O buffers */ spin_lock_irqsave(&port->port_lock, flags); if (port->port.count == 0)