leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

usb: cdnsp: Fix a NULL pointer dereference in cdnsp_endpoint_init()

Browse Source 
In cdnsp_endpoint_init(), cdnsp_ring_alloc() is assigned to pep->ring
and there is a dereference of it in cdnsp_endpoint_init(), which could
lead to a NULL pointer dereference on failure of cdnsp_ring_alloc().

Fix this bug by adding a check of pep->ring.

This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.

Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.

Builds with CONFIG_USB_CDNSP_GADGET=y show no new warnings,
and our static analyzer no longer warns about this code.

Fixes: 3d82904559 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
Cc: stable <stable@vger.kernel.org>
Acked-by: Pawel Laszczak <pawell@cadence.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Link: https://lore.kernel.org/r/20211130172700.206650-1-zhou1615@umn.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Zhou Qingyang 2021-12-01 01:27:00 +08:00 committed by Greg Kroah-Hartman
parent 387c2b6ba1
commit 37307f7020
1 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/usb/cdns3/cdnsp-mem.c
View File

@ -987,6 +987,9 @@ int cdnsp_endpoint_init(struct cdnsp_device *pdev,
/* Set up the endpoint ring. */
pep->ring = cdnsp_ring_alloc(pdev, 2, ring_type, max_packet, mem_flags);
if (!pep->ring)
return -ENOMEM;
pep->skip = false;
/* Fill the endpoint context */