Linux kernel source tree
Go to file
Pu Lehui 1732ebc4a2 riscv, bpf: Fix unpredictable kernel crash about RV64 struct_ops
We encountered a kernel crash triggered by the bpf_tcp_ca testcase as
show below:

Unable to handle kernel paging request at virtual address ff60000088554500
Oops [#1]
...
CPU: 3 PID: 458 Comm: test_progs Tainted: G           OE      6.8.0-rc1-kselftest_plain #1
Hardware name: riscv-virtio,qemu (DT)
epc : 0xff60000088554500
 ra : tcp_ack+0x288/0x1232
epc : ff60000088554500 ra : ffffffff80cc7166 sp : ff2000000117ba50
 gp : ffffffff82587b60 tp : ff60000087be0040 t0 : ff60000088554500
 t1 : ffffffff801ed24e t2 : 0000000000000000 s0 : ff2000000117bbc0
 s1 : 0000000000000500 a0 : ff20000000691000 a1 : 0000000000000018
 a2 : 0000000000000001 a3 : ff60000087be03a0 a4 : 0000000000000000
 a5 : 0000000000000000 a6 : 0000000000000021 a7 : ffffffff8263f880
 s2 : 000000004ac3c13b s3 : 000000004ac3c13a s4 : 0000000000008200
 s5 : 0000000000000001 s6 : 0000000000000104 s7 : ff2000000117bb00
 s8 : ff600000885544c0 s9 : 0000000000000000 s10: ff60000086ff0b80
 s11: 000055557983a9c0 t3 : 0000000000000000 t4 : 000000000000ffc4
 t5 : ffffffff8154f170 t6 : 0000000000000030
status: 0000000200000120 badaddr: ff60000088554500 cause: 000000000000000c
Code: c796 67d7 0000 0000 0052 0002 c13b 4ac3 0000 0000 (0001) 0000
---[ end trace 0000000000000000 ]---

The reason is that commit 2cd3e3772e ("x86/cfi,bpf: Fix bpf_struct_ops
CFI") changes the func_addr of arch_prepare_bpf_trampoline in struct_ops
from NULL to non-NULL, while we use func_addr on RV64 to differentiate
between struct_ops and regular trampoline. When the struct_ops testcase
is triggered, it emits wrong prologue and epilogue, and lead to
unpredictable issues. After commit 2cd3e3772e, we can use
BPF_TRAMP_F_INDIRECT to distinguish them as it always be set in
struct_ops.

Fixes: 2cd3e3772e ("x86/cfi,bpf: Fix bpf_struct_ops CFI")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20240123023207.1917284-1-pulehui@huaweicloud.com
2024-01-23 23:21:38 +01:00
arch riscv, bpf: Fix unpredictable kernel crash about RV64 struct_ops 2024-01-23 23:21:38 +01:00
block for-6.8/block-2024-01-08 2024-01-11 13:58:04 -08:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto crypto: scomp - fix req->dst buffer overflow 2023-12-29 11:25:56 +08:00
Documentation This cycle, I2C removes the currently unused CLASS_DDC support 2024-01-18 17:29:01 -08:00
drivers wireless fixes for v6.8-rc2 2024-01-23 08:38:13 -08:00
fs More eventfs fixes and a seq_buf fix for 6.8: 2024-01-18 14:45:33 -08:00
include udp: fix busy polling 2024-01-21 18:09:30 +00:00
init Driver core changes for 6.8-rc1 2024-01-18 09:48:40 -08:00
io_uring Generic: 2024-01-17 13:03:37 -08:00
ipc shm: Slim down dependencies 2023-12-20 19:26:31 -05:00
kernel Including fixes from bpf and netfilter. 2024-01-18 17:33:50 -08:00
lib cxl for v6.8 2024-01-18 16:22:43 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm memblock: code readability improvement 2024-01-18 16:46:18 -08:00
net wireless fixes for v6.8-rc2 2024-01-23 08:38:13 -08:00
rust Rust changes for v6.8 2024-01-11 13:05:41 -08:00
samples tracing updates for 6.8: 2024-01-18 14:35:29 -08:00
scripts Char/Misc and other Driver changes for 6.8-rc1 2024-01-17 16:47:17 -08:00
security misc cleanups (the part that hadn't been picked by individual fs trees) 2024-01-11 20:23:50 -08:00
sound This cycle, I2C removes the currently unused CLASS_DDC support 2024-01-18 17:29:01 -08:00
tools selftest: Don't reuse port for SO_INCOMING_CPU test. 2024-01-23 10:48:07 +01:00
usr usr/Kconfig: fix typos of "its" 2023-12-20 15:02:58 -08:00
virt Generic: 2024-01-17 13:03:37 -08:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +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: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: generate kernel.spec in rpmbuild/SPECS/ 2023-10-03 20:49:09 +09:00
.mailmap Char/Misc and other Driver changes for 6.8-rc1 2024-01-17 16:47:17 -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 Including fixes from bpf and netfilter. 2024-01-18 17:33:50 -08:00
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 Including fixes from bpf and netfilter. 2024-01-18 17:33:50 -08:00
Makefile Quite a lot of kexec work this time around. Many singleton patches in 2024-01-09 11:46:20 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.