diff options
| author | Mans Rullgard <mans@mansr.com> | 2020-03-16 16:11:35 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-17 20:03:28 +0100 |
| commit | 52974d94a206ce428d9d9b6eaa208238024be82a (patch) | |
| tree | e32d8daf2cd47c9d9caf725280c120a27f1271ed /drivers/usb | |
| parent | e72838d47dc18a066b2b20b9d3f44c93ca82fe96 (diff) | |
| download | linux-52974d94a206ce428d9d9b6eaa208238024be82a.tar.bz2 | |
usb: musb: fix crash with highmen PIO and usbmon
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>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/musb/musb_host.c | 17 |
1 files changed, 5 insertions, 12 deletions
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c index 1c813c37462a..8736f4251a22 100644 --- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -1436,10 +1436,7 @@ 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"); @@ -1447,9 +1444,8 @@ 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 { @@ -1458,11 +1454,6 @@ 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); @@ -1977,8 +1968,10 @@ 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; |