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usb: musb: fix crash with highmen PIO and usbmon

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commit 52974d94a206ce428d9d9b6eaa208238024be82a upstream.

When handling a PIO bulk transfer with highmem buffer, a temporary
mapping is assigned to urb->transfer_buffer.  After the transfer is
complete, an invalid address is left behind in this pointer.  This is
not ordinarily a problem since nothing touches that buffer before the
urb is released.  However, when usbmon is active, usbmon_urb_complete()
calls (indirectly) mon_bin_get_data() which does access the transfer
buffer if it is set.  To prevent an invalid memory access here, reset
urb->transfer_buffer to NULL when finished (musb_host_rx()), or do not
set it at all (musb_host_tx()).

Fixes: 8e8a55165469 ("usb: musb: host: Handle highmem in PIO mode")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Cc: stable@vger.kernel.org
Signed-off-by: Bin Liu <b-liu@ti.com>
Link: https://lore.kernel.org/r/20200316211136.2274-8-b-liu@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mans Rullgard 2020-03-16 16:11:35 -05:00 committed by Greg Kroah-Hartman
parent e68fb968fd
commit 5bece4940e
1 changed files with 5 additions and 12 deletions
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17
drivers/usb/musb/musb_host.c
View File

@ -1494,10 +1494,7 @@ done:
* We need to map sg if the transfer_buffer is
* NULL.
*/
if (!urb->transfer_buffer)
qh->use_sg = true;
if (qh->use_sg) {
if (!urb->transfer_buffer) {
/* sg_miter_start is already done in musb_ep_program */
if (!sg_miter_next(&qh->sg_miter)) {
dev_err(musb->controller, "error: sg list empty\n");
@ -1505,9 +1502,8 @@ done:
status = -EINVAL;
goto done;
}
urb->transfer_buffer = qh->sg_miter.addr;
length = min_t(u32, length, qh->sg_miter.length);
musb_write_fifo(hw_ep, length, urb->transfer_buffer);
musb_write_fifo(hw_ep, length, qh->sg_miter.addr);
qh->sg_miter.consumed = length;
sg_miter_stop(&qh->sg_miter);
} else {
@ -1516,11 +1512,6 @@ done:
qh->segsize = length;
if (qh->use_sg) {
if (offset + length >= urb->transfer_buffer_length)
qh->use_sg = false;
}
musb_ep_select(mbase, epnum);
musb_writew(epio, MUSB_TXCSR,
MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
@ -2038,8 +2029,10 @@ finish:
urb->actual_length += xfer_len;
qh->offset += xfer_len;
if (done) {
if (qh->use_sg)
if (qh->use_sg) {
qh->use_sg = false;
urb->transfer_buffer = NULL;
}
if (urb->status == -EINPROGRESS)
urb->status = status;