lkml.org 
[lkml]   [2015]   [May]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1] usb: dwc2: gadget: fix a memory use-after-free bug
Date
When s3c_hsotg_handle_unaligned_buf_complete() hs_req->req.buf
already destroyed, in s3c_hsotg_unmap_dma(), it touches
hs_req->req.dma again, so s3c_hsotg_unmap_dma() should be called
before s3c_hsotg_handle_unaligned_buf_complete(). Otherwise, it
will cause a bad_page BUG, when allocate this memory page next
time.

This bug led to the following crash:

BUG: Bad page state in process swapper/0 pfn:2bdbc
[ 26.820440] page:eed76780 count:0 mapcount:0 mapping: (null) index:0x0
[ 26.854710] page flags: 0x200(arch_1)
[ 26.885836] page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
[ 26.919179] bad because of flags:
[ 26.948917] page flags: 0x200(arch_1)
[ 26.979100] Modules linked in:
[ 27.008401] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W3.14.0 #17
[ 27.041816] [<c010e1f8>] (unwind_backtrace) from [<c010a704>] (show_stack+0x20/0x24)
[ 27.076108] [<c010a704>] (show_stack) from [<c087eea8>] (dump_stack+0x70/0x8c)
[ 27.110246] [<c087eea8>] (dump_stack) from [<c01ce0b8>] (bad_page+0xfc/0x12c)
[ 27.143958] [<c01ce0b8>] (bad_page) from [<c01ce65c>] (get_page_from_freelist+0x3e4/0x50c)
[ 27.179298] [<c01ce65c>] (get_page_from_freelist) from [<c01ce9a0>] (__alloc_pages_nodemask)
[ 27.216296] [<c01ce9a0>] (__alloc_pages_nodemask) from [<c01cf00c>] (__get_free_pages+0x20/)
[ 27.252326] [<c01cf00c>] (__get_free_pages) from [<c01e5bec>] (kmalloc_order_trace+0x34/0xa)
[ 27.288295] [<c01e5bec>] (kmalloc_order_trace) from [<c0203304>] (__kmalloc+0x40/0x1ac)
[ 27.323751] [<c0203304>] (__kmalloc) from [<c052abc0>] (s3c_hsotg_ep_queue.isra.12+0x7c/0x1)
[ 27.359937] [<c052abc0>] (s3c_hsotg_ep_queue.isra.12) from [<c052af88>] (s3c_hsotg_ep_queue)
[ 27.397478] [<c052af88>] (s3c_hsotg_ep_queue_lock) from [<c0554110>] (rx_submit+0xfc/0x164)
[ 27.433619] [<c0554110>] (rx_submit) from [<c05546e8>] (rx_complete+0x22c/0x230)
[ 27.468872] [<c05546e8>] (rx_complete) from [<c052b528>] (s3c_hsotg_complete_request+0xfc/0)
[ 27.506240] [<c052b528>] (s3c_hsotg_complete_request) from [<c052bba0>] (s3c_hsotg_handle_o)
[ 27.545401] [<c052bba0>] (s3c_hsotg_handle_outdone) from [<c052be70>] (s3c_hsotg_epint+0x2c)
[ 27.583689] [<c052be70>] (s3c_hsotg_epint) from [<c052c750>] (s3c_hsotg_irq+0x1dc/0x4ac)
[ 27.621041] [<c052c750>] (s3c_hsotg_irq) from [<c01682e0>] (handle_irq_event_percpu+0x70/0x)
[ 27.659066] [<c01682e0>] (handle_irq_event_percpu) from [<c01684ec>] (handle_irq_event+0x4c)
[ 27.697322] [<c01684ec>] (handle_irq_event) from [<c016bae0>] (handle_fasteoi_irq+0xc8/0x11)
[ 27.735451] [<c016bae0>] (handle_fasteoi_irq) from [<c0167b8c>] (generic_handle_irq+0x30/0x)
[ 27.773918] [<c0167b8c>] (generic_handle_irq) from [<c0167ca4>] (__handle_domain_irq+0x84/0)
[ 27.812018] [<c0167ca4>] (__handle_domain_irq) from [<c01003b0>] (gic_handle_irq+0x48/0x6c)
[ 27.849695] [<c01003b0>] (gic_handle_irq) from [<c010b340>] (__irq_svc+0x40/0x50)
[ 27.886907] Exception stack(0xc0d01ee0 to 0xc0d01f28)

Signed-off-by: Yunzhi Li <lyz@rock-chips.com>

---

drivers/usb/dwc2/gadget.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 6a30887..8070602 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1389,14 +1389,14 @@ static void s3c_hsotg_complete_request(struct dwc2_hsotg *hsotg,
if (hs_req->req.status == -EINPROGRESS)
hs_req->req.status = result;

+ if (using_dma(hsotg))
+ s3c_hsotg_unmap_dma(hsotg, hs_ep, hs_req);
+
s3c_hsotg_handle_unaligned_buf_complete(hsotg, hs_ep, hs_req);

hs_ep->req = NULL;
list_del_init(&hs_req->queue);

- if (using_dma(hsotg))
- s3c_hsotg_unmap_dma(hsotg, hs_ep, hs_req);
-
/*
* call the complete request with the locks off, just in case the
* request tries to queue more work for this endpoint.
--
2.0.0



\
 
 \ /
  Last update: 2015-05-29 08:01    [W:0.083 / U:50.608 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site