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