RE: [PATCH] xhci: fix list access before init

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



> -----Original Message-----
> From: Sarah Sharp [mailto:sarah.a.sharp@xxxxxxxxxxxxxxx]
> Sent: Thursday, April 04, 2013 12:29 PM
> To: Vladimir Murzin
> Cc: linux-usb@xxxxxxxxxxxxxxx; gregkh@xxxxxxx; dserrg@xxxxxxxxx; Aguirre
> Rodriguez, Sergio A
> Subject: Re: [PATCH] xhci: fix list access before init
> 
> Someone else is already working on a patch to fix part of this:
> 
> http://marc.info/?l=linux-usb&m=136509667003716&w=2
> 
> Please coordinate with them.
> 
> Also, two people trying to solve the same simple bug and using almost
> exactly the same commit messages seems like too much of a coincidence.
> Are you working on the same project or did you both happen to run the
> same static code checking tool at the same time, or ?

I had no idea about this patch, nor had the pleasure to meet Sergey/Vladimir :)

I guess it was really a strange coincidence...

Regards,
Sergio

> 
> Sarah Sharp
> 
> On Thu, Apr 04, 2013 at 08:31:26PM +0400, Vladimir Murzin wrote:
> > Commits
> > 	9574323 xHCI: test USB2 software LPM
> > 	b92cc66 xHCI: add aborting command ring function introduce useful
> > functions which involves lists manipulations.
> >
> > If for whatever reason we fall into fail path in xhci_mem_init() we
> > may access the lists in xhci_mem_cleanup() before they get
> > initialized.
> >
> > The same init-fail-cleanup case is applicable to bw tables too.
> >
> > Fix this by moving list initialization code to the beginning of
> > xhci_mem_init()
> >
> > Reported-by: Sergey Dyasly <dserrg@xxxxxxxxx>
> > Tested-by: Sergey Dyasly <dserrg@xxxxxxxxx>
> > Signed-off-by: Vladimir Murzin <murzin.v@xxxxxxxxx>
> > ---
> >  drivers/usb/host/xhci-mem.c |   37 ++++++++++++++++++++----------------
> -
> >  1 file changed, 20 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
> > index 6dc238c..7b5d2f5 100644
> > --- a/drivers/usb/host/xhci-mem.c
> > +++ b/drivers/usb/host/xhci-mem.c
> > @@ -2123,7 +2123,7 @@ static int xhci_setup_port_arrays(struct xhci_hcd
> *xhci, gfp_t flags)
> >  	__le32 __iomem *addr;
> >  	u32 offset;
> >  	unsigned int num_ports;
> > -	int i, j, port_index;
> > +	int i, port_index;
> >
> >  	addr = &xhci->cap_regs->hcc_params;
> >  	offset = XHCI_HCC_EXT_CAPS(xhci_readl(xhci, addr)); @@ -2138,18
> > +2138,6 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t
> flags)
> >  	if (!xhci->port_array)
> >  		return -ENOMEM;
> >
> > -	xhci->rh_bw = kzalloc(sizeof(*xhci->rh_bw)*num_ports, flags);
> > -	if (!xhci->rh_bw)
> > -		return -ENOMEM;
> > -	for (i = 0; i < num_ports; i++) {
> > -		struct xhci_interval_bw_table *bw_table;
> > -
> > -		INIT_LIST_HEAD(&xhci->rh_bw[i].tts);
> > -		bw_table = &xhci->rh_bw[i].bw_table;
> > -		for (j = 0; j < XHCI_MAX_INTERVAL; j++)
> > -			INIT_LIST_HEAD(&bw_table-
> >interval_bw[j].endpoints);
> > -	}
> > -
> >  	/*
> >  	 * For whatever reason, the first capability offset is from the
> >  	 * capability register base, not from the HCCPARAMS register.
> > @@ -2253,7 +2241,25 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t
> flags)
> >  	u64		val_64;
> >  	struct xhci_segment	*seg;
> >  	u32 page_size, temp;
> > -	int i;
> > +	int i, j, num_ports;
> > +
> > +	INIT_LIST_HEAD(&xhci->cancel_cmd_list);
> > +	INIT_LIST_HEAD(&xhci->lpm_failed_devs);
> > +
> > +	num_ports = HCS_MAX_PORTS(xhci_readl(xhci,
> > +&xhci->cap_regs->hcs_params1));
> > +
> > +	xhci->rh_bw = kzalloc(sizeof(*xhci->rh_bw)*num_ports, flags);
> > +	if (!xhci->rh_bw)
> > +		return -ENOMEM;
> > +
> > +	for (i = 0; i < num_ports; i++) {
> > +		struct xhci_interval_bw_table *bw_table;
> > +
> > +		INIT_LIST_HEAD(&xhci->rh_bw[i].tts);
> > +		bw_table = &xhci->rh_bw[i].bw_table;
> > +		for (j = 0; j < XHCI_MAX_INTERVAL; j++)
> > +			INIT_LIST_HEAD(&bw_table-
> >interval_bw[j].endpoints);
> > +	}
> >
> >  	page_size = xhci_readl(xhci, &xhci->op_regs->page_size);
> >  	xhci_dbg(xhci, "Supported page size register = 0x%x\n", page_size);
> > @@ -2333,7 +2339,6 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t
> flags)
> >  	xhci->cmd_ring = xhci_ring_alloc(xhci, 1, 1, TYPE_COMMAND, flags);
> >  	if (!xhci->cmd_ring)
> >  		goto fail;
> > -	INIT_LIST_HEAD(&xhci->cancel_cmd_list);
> >  	xhci_dbg(xhci, "Allocated command ring at %p\n", xhci->cmd_ring);
> >  	xhci_dbg(xhci, "First segment DMA is 0x%llx\n",
> >  			(unsigned long long)xhci->cmd_ring->first_seg-
> >dma);
> > @@ -2444,8 +2449,6 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t
> flags)
> >  	if (xhci_setup_port_arrays(xhci, flags))
> >  		goto fail;
> >
> > -	INIT_LIST_HEAD(&xhci->lpm_failed_devs);
> > -
> >  	/* Enable USB 3.0 device notifications for function remote wake,
> which
> >  	 * is necessary for allowing USB 3.0 devices to do remote wakeup
> from
> >  	 * U3 (device suspend).
> > --
> > 1.7.10.4
> >
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux