diff mbox series

[V2] usb: musb: Check requset->buf before use to avoid crash issue

Message ID 20231101071421.29462-1-xingxing.luo@unisoc.com (mailing list archive)
State Handled Elsewhere
Headers show
Series [V2] usb: musb: Check requset->buf before use to avoid crash issue | expand

Commit Message

Xingxing Luo Nov. 1, 2023, 7:14 a.m. UTC
When connecting USB to PC, there is a very low probability of kernel
crash. The reason is that in ep0_txstate(), the buf member of struct
usb_request used may be a null pointer. Therefore, it needs to
determine whether it is null before using it.

[ 4888.071462][T597@C0] Call trace:
[ 4888.071467][T597@C0]  musb_default_write_fifo+0xa0/0x1ac [musb_hdrc]
[ 4888.087190][T597@C0]  musb_write_fifo+0x3c/0x90 [musb_hdrc]
[ 4888.099826][T597@C0]  ep0_txstate+0x78/0x218 [musb_hdrc]
[ 4888.153918][T597@C0]  musb_g_ep0_irq+0x3c4/0xe10 [musb_hdrc]
[ 4888.159663][T597@C0]  musb_interrupt+0xab4/0xf1c [musb_hdrc]
[ 4888.165391][T597@C0]  sprd_musb_interrupt+0x1e4/0x484 [musb_sprd]
[ 4888.171447][T597@C0]  __handle_irq_event_percpu+0xd8/0x2f8
[ 4888.176901][T597@C0]  handle_irq_event+0x70/0xe4
[ 4888.181487][T597@C0]  handle_fasteoi_irq+0x15c/0x230
[ 4888.186420][T597@C0]  handle_domain_irq+0x88/0xfc
[ 4888.191090][T597@C0]  gic_handle_irq+0x60/0x138
[ 4888.195591][T597@C0]  call_on_irq_stack+0x40/0x70
[ 4888.200263][T597@C0]  do_interrupt_handler+0x50/0xac
[ 4888.205196][T597@C0]  el1_interrupt+0x34/0x64
[ 4888.209524][T597@C0]  el1h_64_irq_handler+0x1c/0x2c
[ 4888.214370][T597@C0]  el1h_64_irq+0x7c/0x80
[ 4888.218525][T597@C0]  __check_heap_object+0x1ac/0x1fc
[ 4888.223544][T597@C0]  __check_object_size+0x10c/0x20c
[ 4888.228563][T597@C0]  simple_copy_to_iter+0x40/0x74
[ 4888.233410][T597@C0]  __skb_datagram_iter+0xa0/0x310
[ 4888.238343][T597@C0]  skb_copy_datagram_iter+0x44/0x110
[ 4888.243535][T597@C0]  netlink_recvmsg+0xdc/0x364
[ 4888.248123][T597@C0]  ____sys_recvmsg.llvm.16749613423860851707+0x358/0x6c0
[ 4888.255045][T597@C0]  ___sys_recvmsg+0xe0/0x1dc
[ 4888.259544][T597@C0]  __arm64_sys_recvmsg+0xc4/0x10c
[ 4888.264478][T597@C0]  invoke_syscall+0x6c/0x15c
[ 4888.268976][T597@C0]  el0_svc_common.llvm.12373701176611417606+0xd4/0x120
[ 4888.275726][T597@C0]  do_el0_svc+0x34/0xac
[ 4888.279795][T597@C0]  el0_svc+0x28/0x90
[ 4888.283603][T597@C0]  el0t_64_sync_handler+0x88/0xec
[ 4888.288548][T597@C0]  el0t_64_sync+0x1b4/0x1b8
[ 4888.292956][T597@C0] Code: 540002c3 53027ea8 aa1303e9 71000508 (b840452a)
[ 4888.299789][T597@C0] ---[ end trace 14a301b7253e83cc ]---

Fixes: 550a7375fe72 ("USB: Add MUSB and TUSB support")
Signed-off-by: Xingxing Luo <xingxing.luo@unisoc.com>
---
v1 -> v2: - Fixed a spelling error
          - Add the fixed commit id

 drivers/usb/musb/musb_gadget_ep0.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Greg KH Nov. 1, 2023, 7:29 a.m. UTC | #1
On Wed, Nov 01, 2023 at 03:14:21PM +0800, Xingxing Luo wrote:
> When connecting USB to PC, there is a very low probability of kernel
> crash. The reason is that in ep0_txstate(), the buf member of struct
> usb_request used may be a null pointer. Therefore, it needs to
> determine whether it is null before using it.
> 
> [ 4888.071462][T597@C0] Call trace:
> [ 4888.071467][T597@C0]  musb_default_write_fifo+0xa0/0x1ac [musb_hdrc]
> [ 4888.087190][T597@C0]  musb_write_fifo+0x3c/0x90 [musb_hdrc]
> [ 4888.099826][T597@C0]  ep0_txstate+0x78/0x218 [musb_hdrc]
> [ 4888.153918][T597@C0]  musb_g_ep0_irq+0x3c4/0xe10 [musb_hdrc]
> [ 4888.159663][T597@C0]  musb_interrupt+0xab4/0xf1c [musb_hdrc]
> [ 4888.165391][T597@C0]  sprd_musb_interrupt+0x1e4/0x484 [musb_sprd]
> [ 4888.171447][T597@C0]  __handle_irq_event_percpu+0xd8/0x2f8
> [ 4888.176901][T597@C0]  handle_irq_event+0x70/0xe4
> [ 4888.181487][T597@C0]  handle_fasteoi_irq+0x15c/0x230
> [ 4888.186420][T597@C0]  handle_domain_irq+0x88/0xfc
> [ 4888.191090][T597@C0]  gic_handle_irq+0x60/0x138
> [ 4888.195591][T597@C0]  call_on_irq_stack+0x40/0x70
> [ 4888.200263][T597@C0]  do_interrupt_handler+0x50/0xac
> [ 4888.205196][T597@C0]  el1_interrupt+0x34/0x64
> [ 4888.209524][T597@C0]  el1h_64_irq_handler+0x1c/0x2c
> [ 4888.214370][T597@C0]  el1h_64_irq+0x7c/0x80
> [ 4888.218525][T597@C0]  __check_heap_object+0x1ac/0x1fc
> [ 4888.223544][T597@C0]  __check_object_size+0x10c/0x20c
> [ 4888.228563][T597@C0]  simple_copy_to_iter+0x40/0x74
> [ 4888.233410][T597@C0]  __skb_datagram_iter+0xa0/0x310
> [ 4888.238343][T597@C0]  skb_copy_datagram_iter+0x44/0x110
> [ 4888.243535][T597@C0]  netlink_recvmsg+0xdc/0x364
> [ 4888.248123][T597@C0]  ____sys_recvmsg.llvm.16749613423860851707+0x358/0x6c0
> [ 4888.255045][T597@C0]  ___sys_recvmsg+0xe0/0x1dc
> [ 4888.259544][T597@C0]  __arm64_sys_recvmsg+0xc4/0x10c
> [ 4888.264478][T597@C0]  invoke_syscall+0x6c/0x15c
> [ 4888.268976][T597@C0]  el0_svc_common.llvm.12373701176611417606+0xd4/0x120
> [ 4888.275726][T597@C0]  do_el0_svc+0x34/0xac
> [ 4888.279795][T597@C0]  el0_svc+0x28/0x90
> [ 4888.283603][T597@C0]  el0t_64_sync_handler+0x88/0xec
> [ 4888.288548][T597@C0]  el0t_64_sync+0x1b4/0x1b8
> [ 4888.292956][T597@C0] Code: 540002c3 53027ea8 aa1303e9 71000508 (b840452a)
> [ 4888.299789][T597@C0] ---[ end trace 14a301b7253e83cc ]---
> 
> Fixes: 550a7375fe72 ("USB: Add MUSB and TUSB support")
> Signed-off-by: Xingxing Luo <xingxing.luo@unisoc.com>
> ---
> v1 -> v2: - Fixed a spelling error
>           - Add the fixed commit id
> 
>  drivers/usb/musb/musb_gadget_ep0.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
> index 6d7336727388..19eb7a5e1fdc 100644
> --- a/drivers/usb/musb/musb_gadget_ep0.c
> +++ b/drivers/usb/musb/musb_gadget_ep0.c
> @@ -531,6 +531,11 @@ static void ep0_txstate(struct musb *musb)
>  
>  	request = &req->request;
>  
> +	if (!request->buf) {
> +		musb_dbg(musb, "request->buf is NULL");
> +		return;
> +	}
> +
>  	/* load the data */
>  	fifo_src = (u8 *) request->buf + request->actual;
>  	fifo_count = min((unsigned) MUSB_EP0_FIFOSIZE,
> -- 
> 2.17.1
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- You have marked a patch with a "Fixes:" tag for a commit that is in an
  older released kernel, yet you do not have a cc: stable line in the
  signed-off-by area at all, which means that the patch will not be
  applied to any older kernel releases.  To properly fix this, please
  follow the documented rules in the
  Documentation/process/stable-kernel-rules.rst file for how to resolve
  this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot
Greg KH Nov. 1, 2023, 7:31 a.m. UTC | #2
On Wed, Nov 01, 2023 at 03:14:21PM +0800, Xingxing Luo wrote:
> When connecting USB to PC, there is a very low probability of kernel
> crash. The reason is that in ep0_txstate(), the buf member of struct
> usb_request used may be a null pointer. Therefore, it needs to
> determine whether it is null before using it.
> 
> [ 4888.071462][T597@C0] Call trace:
> [ 4888.071467][T597@C0]  musb_default_write_fifo+0xa0/0x1ac [musb_hdrc]
> [ 4888.087190][T597@C0]  musb_write_fifo+0x3c/0x90 [musb_hdrc]
> [ 4888.099826][T597@C0]  ep0_txstate+0x78/0x218 [musb_hdrc]
> [ 4888.153918][T597@C0]  musb_g_ep0_irq+0x3c4/0xe10 [musb_hdrc]
> [ 4888.159663][T597@C0]  musb_interrupt+0xab4/0xf1c [musb_hdrc]
> [ 4888.165391][T597@C0]  sprd_musb_interrupt+0x1e4/0x484 [musb_sprd]
> [ 4888.171447][T597@C0]  __handle_irq_event_percpu+0xd8/0x2f8
> [ 4888.176901][T597@C0]  handle_irq_event+0x70/0xe4
> [ 4888.181487][T597@C0]  handle_fasteoi_irq+0x15c/0x230
> [ 4888.186420][T597@C0]  handle_domain_irq+0x88/0xfc
> [ 4888.191090][T597@C0]  gic_handle_irq+0x60/0x138
> [ 4888.195591][T597@C0]  call_on_irq_stack+0x40/0x70
> [ 4888.200263][T597@C0]  do_interrupt_handler+0x50/0xac
> [ 4888.205196][T597@C0]  el1_interrupt+0x34/0x64
> [ 4888.209524][T597@C0]  el1h_64_irq_handler+0x1c/0x2c
> [ 4888.214370][T597@C0]  el1h_64_irq+0x7c/0x80
> [ 4888.218525][T597@C0]  __check_heap_object+0x1ac/0x1fc
> [ 4888.223544][T597@C0]  __check_object_size+0x10c/0x20c
> [ 4888.228563][T597@C0]  simple_copy_to_iter+0x40/0x74
> [ 4888.233410][T597@C0]  __skb_datagram_iter+0xa0/0x310
> [ 4888.238343][T597@C0]  skb_copy_datagram_iter+0x44/0x110
> [ 4888.243535][T597@C0]  netlink_recvmsg+0xdc/0x364
> [ 4888.248123][T597@C0]  ____sys_recvmsg.llvm.16749613423860851707+0x358/0x6c0
> [ 4888.255045][T597@C0]  ___sys_recvmsg+0xe0/0x1dc
> [ 4888.259544][T597@C0]  __arm64_sys_recvmsg+0xc4/0x10c
> [ 4888.264478][T597@C0]  invoke_syscall+0x6c/0x15c
> [ 4888.268976][T597@C0]  el0_svc_common.llvm.12373701176611417606+0xd4/0x120
> [ 4888.275726][T597@C0]  do_el0_svc+0x34/0xac
> [ 4888.279795][T597@C0]  el0_svc+0x28/0x90
> [ 4888.283603][T597@C0]  el0t_64_sync_handler+0x88/0xec
> [ 4888.288548][T597@C0]  el0t_64_sync+0x1b4/0x1b8
> [ 4888.292956][T597@C0] Code: 540002c3 53027ea8 aa1303e9 71000508 (b840452a)
> [ 4888.299789][T597@C0] ---[ end trace 14a301b7253e83cc ]---
> 
> Fixes: 550a7375fe72 ("USB: Add MUSB and TUSB support")
> Signed-off-by: Xingxing Luo <xingxing.luo@unisoc.com>
> ---
> v1 -> v2: - Fixed a spelling error
>           - Add the fixed commit id
> 
>  drivers/usb/musb/musb_gadget_ep0.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
> index 6d7336727388..19eb7a5e1fdc 100644
> --- a/drivers/usb/musb/musb_gadget_ep0.c
> +++ b/drivers/usb/musb/musb_gadget_ep0.c
> @@ -531,6 +531,11 @@ static void ep0_txstate(struct musb *musb)
>  
>  	request = &req->request;
>  
> +	if (!request->buf) {
> +		musb_dbg(musb, "request->buf is NULL");

Why is this debug line needed?

> +		return;

Shouldn't we be reporting an error here somehow?

And why has this issue never been seen before in this driver?  This is a
very old driver, with millions, if not billions, of working systems with
it.  What caused this to suddenly start happening?

thanks,

greg k-h
Sergey Shtylyov Nov. 1, 2023, 8:37 a.m. UTC | #3
Hello!

   You have have a typo in the subject: s/requset/request/...

MBR, Sergey
xingxing luo Nov. 13, 2023, 11:50 a.m. UTC | #4
On Wed, Nov 1, 2023 at 3:31 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Wed, Nov 01, 2023 at 03:14:21PM +0800, Xingxing Luo wrote:
> > When connecting USB to PC, there is a very low probability of kernel
> > crash. The reason is that in ep0_txstate(), the buf member of struct
> > usb_request used may be a null pointer. Therefore, it needs to
> > determine whether it is null before using it.
> >
> > [ 4888.071462][T597@C0] Call trace:
> > [ 4888.071467][T597@C0]  musb_default_write_fifo+0xa0/0x1ac [musb_hdrc]
> > [ 4888.087190][T597@C0]  musb_write_fifo+0x3c/0x90 [musb_hdrc]
> > [ 4888.099826][T597@C0]  ep0_txstate+0x78/0x218 [musb_hdrc]
> > [ 4888.153918][T597@C0]  musb_g_ep0_irq+0x3c4/0xe10 [musb_hdrc]
> > [ 4888.159663][T597@C0]  musb_interrupt+0xab4/0xf1c [musb_hdrc]
> > [ 4888.165391][T597@C0]  sprd_musb_interrupt+0x1e4/0x484 [musb_sprd]
> > [ 4888.171447][T597@C0]  __handle_irq_event_percpu+0xd8/0x2f8
> > [ 4888.176901][T597@C0]  handle_irq_event+0x70/0xe4
> > [ 4888.181487][T597@C0]  handle_fasteoi_irq+0x15c/0x230
> > [ 4888.186420][T597@C0]  handle_domain_irq+0x88/0xfc
> > [ 4888.191090][T597@C0]  gic_handle_irq+0x60/0x138
> > [ 4888.195591][T597@C0]  call_on_irq_stack+0x40/0x70
> > [ 4888.200263][T597@C0]  do_interrupt_handler+0x50/0xac
> > [ 4888.205196][T597@C0]  el1_interrupt+0x34/0x64
> > [ 4888.209524][T597@C0]  el1h_64_irq_handler+0x1c/0x2c
> > [ 4888.214370][T597@C0]  el1h_64_irq+0x7c/0x80
> > [ 4888.218525][T597@C0]  __check_heap_object+0x1ac/0x1fc
> > [ 4888.223544][T597@C0]  __check_object_size+0x10c/0x20c
> > [ 4888.228563][T597@C0]  simple_copy_to_iter+0x40/0x74
> > [ 4888.233410][T597@C0]  __skb_datagram_iter+0xa0/0x310
> > [ 4888.238343][T597@C0]  skb_copy_datagram_iter+0x44/0x110
> > [ 4888.243535][T597@C0]  netlink_recvmsg+0xdc/0x364
> > [ 4888.248123][T597@C0]  ____sys_recvmsg.llvm.16749613423860851707+0x358/0x6c0
> > [ 4888.255045][T597@C0]  ___sys_recvmsg+0xe0/0x1dc
> > [ 4888.259544][T597@C0]  __arm64_sys_recvmsg+0xc4/0x10c
> > [ 4888.264478][T597@C0]  invoke_syscall+0x6c/0x15c
> > [ 4888.268976][T597@C0]  el0_svc_common.llvm.12373701176611417606+0xd4/0x120
> > [ 4888.275726][T597@C0]  do_el0_svc+0x34/0xac
> > [ 4888.279795][T597@C0]  el0_svc+0x28/0x90
> > [ 4888.283603][T597@C0]  el0t_64_sync_handler+0x88/0xec
> > [ 4888.288548][T597@C0]  el0t_64_sync+0x1b4/0x1b8
> > [ 4888.292956][T597@C0] Code: 540002c3 53027ea8 aa1303e9 71000508 (b840452a)
> > [ 4888.299789][T597@C0] ---[ end trace 14a301b7253e83cc ]---
> >
> > Fixes: 550a7375fe72 ("USB: Add MUSB and TUSB support")
> > Signed-off-by: Xingxing Luo <xingxing.luo@unisoc.com>
> > ---
> > v1 -> v2: - Fixed a spelling error
> >           - Add the fixed commit id
> >
> >  drivers/usb/musb/musb_gadget_ep0.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> >
> > diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
> > index 6d7336727388..19eb7a5e1fdc 100644
> > --- a/drivers/usb/musb/musb_gadget_ep0.c
> > +++ b/drivers/usb/musb/musb_gadget_ep0.c
> > @@ -531,6 +531,11 @@ static void ep0_txstate(struct musb *musb)
> >
> >       request = &req->request;
> >
> > +     if (!request->buf) {
> > +             musb_dbg(musb, "request->buf is NULL");
>
> Why is this debug line needed?
>
> > +             return;
>
> Shouldn't we be reporting an error here somehow?
>

This is a good suggestion, I will add it in the next version.

> And why has this issue never been seen before in this driver?  This is a
> very old driver, with millions, if not billions, of working systems with
> it.  What caused this to suddenly start happening?
>

This problem occurs in a special scenario and is also a very
low-probability problem.
When our machine is used as a device and connected to the computer, due to some
unknown reason, the USB cable is not pulled out, but the USB driver is
notified to
pull out. Out, the gadget is processing the unbind process. When the
execution is
completed, request->buf is released and points to NULL. At the same
time, since the
USB is not physically disconnected at this time, the USB will receive
an interrupt and
use ep0 for control transmission. The request->buf of ep0 used at this
time has been
used in the gadget unbind process. It is released and points to NULL,
thus using a null
pointer, causing the kernel to crash. Therefore, we think it would be
better to determine
whether it is null before using request->buf.

> thanks,
>
> greg k-h
diff mbox series

Patch

diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
index 6d7336727388..19eb7a5e1fdc 100644
--- a/drivers/usb/musb/musb_gadget_ep0.c
+++ b/drivers/usb/musb/musb_gadget_ep0.c
@@ -531,6 +531,11 @@  static void ep0_txstate(struct musb *musb)
 
 	request = &req->request;
 
+	if (!request->buf) {
+		musb_dbg(musb, "request->buf is NULL");
+		return;
+	}
+
 	/* load the data */
 	fifo_src = (u8 *) request->buf + request->actual;
 	fifo_count = min((unsigned) MUSB_EP0_FIFOSIZE,