patch "Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y" added to usb-linus
From: <gregkh@linuxfoundation.org>
Date: 2016-11-15 10:10:37
Subsystem:
the rest, usb mass storage driver, usb subsystem · Maintainers:
Linus Torvalds, Alan Stern, Greg Kroah-Hartman
This is a note to let you know that I've just added the patch titled
Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
From 2ce9d2272b98743b911196c49e7af5841381c206 Mon Sep 17 00:00:00 2001
From: Petr Vandrovec <redacted> Date: Thu, 10 Nov 2016 13:57:14 -0800 Subject: Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y Some code (all error handling) submits CDBs that are allocated on the stack. This breaks with CB/CBI code that tries to create URB directly from SCSI command buffer - which happens to be in vmalloced memory with vmalloced kernel stacks. Let's make copy of the command in usb_stor_CB_transport. Signed-off-by: Petr Vandrovec <redacted> Cc: stable <redacted> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/usb/storage/transport.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index ffd086733421..1a59f335b063 100644
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c@@ -954,10 +954,15 @@ int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) /* COMMAND STAGE */ /* let's send the command via the control pipe */ + /* + * Command is sometime (f.e. after scsi_eh_prep_cmnd) on the stack. + * Stack may be vmallocated. So no DMA for us. Make a copy. + */ + memcpy(us->iobuf, srb->cmnd, srb->cmd_len); result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe, US_CBI_ADSC, USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, - us->ifnum, srb->cmnd, srb->cmd_len); + us->ifnum, us->iobuf, srb->cmd_len); /* check the return code for the command */ usb_stor_dbg(us, "Call to usb_stor_ctrl_transfer() returned %d\n",
--
2.10.2