On Fri, Oct 27, 2023 at 6:54 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, Oct 23, 2023 at 05:31:53PM +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 ]--- > > > > Signed-off-by: Xingxing Luo <xingxing.luo@xxxxxxxxxx> > > --- > > 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..5d0629866128 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 (!requset->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 > > This patch does not even build, how did you test it? > I have verified this patch on our platform, which is unisoc, and it can fix the kernel crash problem. However, it seems that there is a spelling error in this patch, I will fix it in the next version. > And what commit id does this fix? commit id: 550a7375fe720924241f0eb76e4a5c1a3eb8c32f > > thanks, > > greg k-h