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
Tudor Ambarus ff484163df net: cdc_ncm: Deal with too low values of dwNtbOutMaxSize
[ Upstream commit 7e01c7f7046efc2c7c192c3619db43292b98e997 ]

Currently in cdc_ncm_check_tx_max(), if dwNtbOutMaxSize is lower than
the calculated "min" value, but greater than zero, the logic sets
tx_max to dwNtbOutMaxSize. This is then used to allocate a new SKB in
cdc_ncm_fill_tx_frame() where all the data is handled.

For small values of dwNtbOutMaxSize the memory allocated during
alloc_skb(dwNtbOutMaxSize, GFP_ATOMIC) will have the same size, due to
how size is aligned at alloc time:
	size = SKB_DATA_ALIGN(size);
        size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
Thus we hit the same bug that we tried to squash with
commit 2be6d4d16a084 ("net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero")

Low values of dwNtbOutMaxSize do not cause an issue presently because at
alloc_skb() time more memory (512b) is allocated than required for the
SKB headers alone (320b), leaving some space (512b - 320b = 192b)
for CDC data (172b).

However, if more elements (for example 3 x u64 = [24b]) were added to
one of the SKB header structs, say 'struct skb_shared_info',
increasing its original size (320b [320b aligned]) to something larger
(344b [384b aligned]), then suddenly the CDC data (172b) no longer
fits in the spare SKB data area (512b - 384b = 128b).

Consequently the SKB bounds checking semantics fails and panics:

skbuff: skb_over_panic: text:ffffffff831f755b len:184 put:172 head:ffff88811f1c6c00 data:ffff88811f1c6c00 tail:0xb8 end:0x80 dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:113!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 57 Comm: kworker/0:2 Not tainted 5.15.106-syzkaller-00249-g19c0ed55a470 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Workqueue: mld mld_ifc_work
RIP: 0010:skb_panic net/core/skbuff.c:113 [inline]
RIP: 0010:skb_over_panic+0x14c/0x150 net/core/skbuff.c:118
[snip]
Call Trace:
 <TASK>
 skb_put+0x151/0x210 net/core/skbuff.c:2047
 skb_put_zero include/linux/skbuff.h:2422 [inline]
 cdc_ncm_ndp16 drivers/net/usb/cdc_ncm.c:1131 [inline]
 cdc_ncm_fill_tx_frame+0x11ab/0x3da0 drivers/net/usb/cdc_ncm.c:1308
 cdc_ncm_tx_fixup+0xa3/0x100

Deal with too low values of dwNtbOutMaxSize, clamp it in the range
[USB_CDC_NCM_NTB_MIN_OUT_SIZE, CDC_NCM_NTB_MAX_SIZE_TX]. We ensure
enough data space is allocated to handle CDC data by making sure
dwNtbOutMaxSize is not smaller than USB_CDC_NCM_NTB_MIN_OUT_SIZE.

Fixes: 289507d336 ("net: cdc_ncm: use sysfs for rx/tx aggregation tuning")
Cc: stable@vger.kernel.org
Reported-by: syzbot+9f575a1f15fc0c01ed69@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=b982f1059506db48409d
Link: https://lore.kernel.org/all/20211202143437.1411410-1-lee.jones@linaro.org/
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230517133808.1873695-2-tudor.ambarus@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-05 08:17:31 +02:00
arch x86/show_trace_log_lvl: Ensure stack pointer is aligned, again 2023-05-30 12:44:10 +01:00
block
certs
crypto crypto: drbg - Only fail when jent is unavailable in FIPS mode 2023-05-17 11:35:42 +02:00
Documentation media: uapi: add MEDIA_BUS_FMT_METADATA_FIXED media bus format. 2023-05-17 11:35:36 +02:00
drivers net: cdc_ncm: Deal with too low values of dwNtbOutMaxSize 2023-06-05 08:17:31 +02:00
fs btrfs: use nofs when cleaning up aborted transactions 2023-05-30 12:44:09 +01:00
include cdc_ncm: Implement the 32-bit version of NCM Transfer Block 2023-06-05 08:17:31 +02:00
init
ipc
kernel bpf: Fix mask generation for 32-bit narrow loads of 64-bit fields 2023-05-30 12:44:10 +01:00
lib debugobjects: Don't wake up kswapd from fill_pool() 2023-05-30 12:44:09 +01:00
LICENSES
mm mm/page_alloc: fix potential deadlock on zonelist_update_seq seqlock 2023-05-17 11:36:05 +02:00
net ipv6: Fix out-of-bounds access in ipv6_find_tlv() 2023-05-30 12:44:10 +01:00
samples samples/bpf: Fix fout leak in hbm's run_bpf_prog 2023-05-30 12:44:03 +01:00
scripts recordmcount: Fix memory leaks in the uwrite function 2023-05-30 12:44:04 +01:00
security
sound ALSA: hda/realtek: Enable headset onLenovo M70/M90 2023-05-30 12:44:09 +01:00
tools selftests: fib_tests: mute cleanup error message 2023-05-30 12:44:10 +01:00
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile Linux 5.4.244 2023-05-30 12:44:11 +01:00
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.