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authorMans Rullgard <mans@mansr.com>2020-03-16 16:11:35 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-03-17 20:03:28 +0100
commit52974d94a206ce428d9d9b6eaa208238024be82a (patch)
treee32d8daf2cd47c9d9caf725280c120a27f1271ed /drivers/usb
parente72838d47dc18a066b2b20b9d3f44c93ca82fe96 (diff)
downloadlinux-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.c17
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;