kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-09 18:15:49 +00:00
Code Issues Releases Packages Activity
No description
1,141,142 commits 116 branches 5,788 tags 5.6 GiB
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Kui-Feng Lee 3331d34160 bpf: Fix the kernel crash caused by bpf_setsockopt(). 
[ Upstream commit 5416c9aea8 ]

The kernel crash was caused by a BPF program attached to the
"lsm_cgroup/socket_sock_rcv_skb" hook, which performed a call to
`bpf_setsockopt()` in order to set the TCP_NODELAY flag as an
example. Flags like TCP_NODELAY can prompt the kernel to flush a
socket's outgoing queue, and this hook
"lsm_cgroup/socket_sock_rcv_skb" is frequently triggered by
softirqs. The issue was that in certain circumstances, when
`tcp_write_xmit()` was called to flush the queue, it would also allow
BH (bottom-half) to run. This could lead to our program attempting to
flush the same socket recursively, which caused a `skbuff` to be
unlinked twice.

`security_sock_rcv_skb()` is triggered by `tcp_filter()`. This occurs
before the sock ownership is checked in `tcp_v4_rcv()`. Consequently,
if a bpf program runs on `security_sock_rcv_skb()` while under softirq
conditions, it may not possess the lock needed for `bpf_setsockopt()`,
thus presenting an issue.

The patch fixes this issue by ensuring that a BPF program attached to
the "lsm_cgroup/socket_sock_rcv_skb" hook is not allowed to call
`bpf_setsockopt()`.

The differences from v1 are
 - changing commit log to explain holding the lock of the sock,
 - emphasizing that TCP_NODELAY is not the only flag, and
 - adding the fixes tag.

v1: https://lore.kernel.org/bpf/20230125000244.1109228-1-kuifeng@meta.com/

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Fixes: 9113d7e48e ("bpf: expose bpf_{g,s}etsockopt to lsm cgroup")
Link: https://lore.kernel.org/r/20230127001732.4162630-1-kuifeng@meta.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2023-02-09 11:28:02 +01:00
arch arm64: dts: imx8mm-verdin: Do not power down eth-phy 2023-02-09 11:28:02 +01:00
block block: fix hctx checks for batch allocation 2023-02-06 08:06:33 +01:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto crypto: tcrypt - Fix multibuffer skcipher speed test mem leak 2022-12-31 13:32:34 +01:00
Documentation dt-bindings: i2c: renesas,rzv2m: Fix SoC specific string 2023-02-01 08:34:51 +01:00
drivers scsi: Revert "scsi: core: map PQ=1, PDT=other values to SCSI_SCAN_TARGET_PRESENT" 2023-02-09 11:28:02 +01:00
fs cifs: fix return of uninitialized rc in dfs_cache_update_tgthint() 2023-02-06 08:06:33 +01:00
include bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener 2023-02-09 11:28:01 +01:00
init gcc: disable -Warray-bounds for gcc-11 too 2023-01-14 10:33:43 +01:00
io_uring io_uring: always prep_async for drain requests 2023-02-01 08:34:42 +01:00
ipc ipc: fix memory leak in init_mqueue_fs() 2022-12-31 13:32:01 +01:00
kernel bpf: Fix the kernel crash caused by bpf_setsockopt(). 2023-02-09 11:28:02 +01:00
lib netlink: prevent potential spectre v1 gadgets 2023-02-01 08:34:43 +01:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Revert "mm/compaction: fix set skip in fast_find_migrateblock" 2023-02-01 08:34:49 +01:00
net bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener 2023-02-09 11:28:01 +01:00
rust rust: print: avoid evaluating arguments in pr_* macros in unsafe blocks 2023-02-06 08:06:34 +01:00
samples ftrace: Export ftrace_free_filter() to modules 2023-02-01 08:34:37 +01:00
scripts Fix up more non-executable files marked executable 2023-02-01 08:34:49 +01:00
security tomoyo: fix broken dependency on *.conf.default 2023-02-01 08:34:06 +01:00
sound ASoC: SOF: ipc4-mtrace: prevent underflow in sof_ipc4_priority_mask_dfs_write() 2023-02-09 11:28:01 +01:00
tools selftests/filesystems: grant executable permission to run_fat_tests.sh 2023-02-09 11:28:01 +01:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt kvm/vfio: Fix potential deadlock on vfio group_lock 2023-02-01 08:34:36 +01:00
.clang-format inet: ping: use hlist_nulls rcu iterator during lookup 2022-12-01 12:42:46 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS panic: Expose "warn_count" to sysfs 2023-01-24 07:24:41 +01:00
Makefile Linux 6.1.10 2023-02-06 08:06:34 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.