No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Sergey Ryazanov 457d9401b8 usb: cdc-wdm: fix reading stuck on device close
commit 01e01f5c89773c600a9f0b32c888de0146066c3a upstream.

cdc-wdm tracks whether a response reading request is in-progress and
blocks the next request from being sent until the previous request is
completed. As soon as last user closes the cdc-wdm device file, the
driver cancels any ongoing requests, resets the pending response
counter, but leaves the response reading in-progress flag
(WDM_RESPONDING) untouched.

So if the user closes the device file during the response receive
request is being performed, no more data will be obtained from the
modem. The request will be cancelled, effectively preventing the
WDM_RESPONDING flag from being reseted. Keeping the flag set will
prevent a new response receive request from being sent, permanently
blocking the read path. The read path will staying blocked until the
module will be reloaded or till the modem will be re-attached.

This stuck has been observed with a Huawei E3372 modem attached to an
OpenWrt router and using the comgt utility to set up a network
connection.

Fix this issue by clearing the WDM_RESPONDING flag on the device file
close.

Without this fix, the device reading stuck can be easily reproduced in a
few connection establishing attempts. With this fix, a load test for
modem connection re-establishing worked for several hours without any
issues.

Fixes: 922a5eadd5 ("usb: cdc-wdm: Fix race between autosuspend and reading from the device")
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20220501175828.8185-1-ryazanov.s.a@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-18 09:47:26 +02:00
arch s390: disable -Warray-bounds 2022-05-18 09:47:26 +02:00
block block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern 2022-05-12 12:23:48 +02:00
certs
crypto crypto: authenc - Fix sleep in atomic context in decrypt_tail 2022-04-15 14:18:04 +02:00
Documentation arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 19:54:46 +02:00
drivers usb: cdc-wdm: fix reading stuck on device close 2022-05-18 09:47:26 +02:00
fs gfs2: Fix filesystem block deallocation for short writes 2022-05-18 09:47:26 +02:00
include net/sched: act_pedit: really ensure the skb is writable 2022-05-18 09:47:25 +02:00
init init/main.c: return 1 from handled __setup() functions 2022-04-15 14:18:35 +02:00
ipc shm: extend forced shm destroy to support objects from several IPC nses 2021-12-01 09:23:35 +01:00
kernel genirq: Synchronize interrupt thread startup 2022-05-12 12:23:41 +02:00
lib dim: initialize all struct fields 2022-05-18 09:47:25 +02:00
LICENSES
mm mm: userfaultfd: fix missing cache flush in mcopy_atomic_pte() and __mcopy_atomic() 2022-05-15 19:54:47 +02:00
net tcp: resalt the secret every 10 seconds 2022-05-18 09:47:26 +02:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-17 09:48:39 +01:00
scripts gcc-plugins: latent_entropy: use /dev/urandom 2022-04-20 09:19:38 +02:00
security Fix incorrect type in assignment of ipv6 port for audit 2022-04-15 14:18:22 +02:00
sound ASoC: ops: Validate input values in snd_soc_put_volsw_range() 2022-05-18 09:47:26 +02:00
tools x86: xen: insn: Decode Xen and KVM emulate-prefix signature 2022-05-15 19:54:47 +02:00
usr
virt KVM: Prevent module exit until all VMs are freed 2022-04-15 14:18:27 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile Linux 5.4.194 2022-05-15 19:54:48 +02:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.