kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-16 22:39:48 +00:00
Code Issues Releases Packages Activity
No description
1,015,683 commits 116 branches 5,798 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
Steven Rostedt (VMware) 751d51f3e9 tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing 
commit 9913d5745b upstream.

All internal use cases for tracepoint_probe_register() is set to not ever
be called with the same function and data. If it is, it is considered a
bug, as that means the accounting of handling tracepoints is corrupted.
If the function and data for a tracepoint is already registered when
tracepoint_probe_register() is called, it will call WARN_ON_ONCE() and
return with EEXISTS.

The BPF system call can end up calling tracepoint_probe_register() with
the same data, which now means that this can trigger the warning because
of a user space process. As WARN_ON_ONCE() should not be called because
user space called a system call with bad data, there needs to be a way to
register a tracepoint without triggering a warning.

Enter tracepoint_probe_register_may_exist(), which can be called, but will
not cause a WARN_ON() if the probe already exists. It will still error out
with EEXIST, which will then be sent to the user space that performed the
BPF system call.

This keeps the previous testing for issues with other users of the
tracepoint code, while letting BPF call it with duplicated data and not
warn about it.

Link: https://lore.kernel.org/lkml/20210626135845.4080-1-penguin-kernel@I-love.SAKURA.ne.jp/
Link: https://syzkaller.appspot.com/bug?id=41f4318cf01762389f4d1c1c459da4f542fe5153

Cc: stable@vger.kernel.org
Fixes: c4f6699dfc ("bpf: introduce BPF_RAW_TRACEPOINT")
Reported-by: syzbot <syzbot+721aa903751db87aa244@syzkaller.appspotmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot+721aa903751db87aa244@syzkaller.appspotmail.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2021-07-14 17:06:17 +02:00
arch s390: mm: Fix secure storage access exception handling 2021-07-14 17:06:13 +02:00
block block-5.13-2021-05-22 2021-05-22 07:40:34 -10:00
certs Kbuild updates for v5.13 (2nd) 2021-05-08 10:00:11 -07:00
crypto async_xor: check src_offs is not NULL before updating it 2021-06-10 19:40:14 -07:00
Documentation RISC-V Fixes for 5.13-rc7 2021-06-19 08:45:34 -07:00
drivers rsi: fix AP mode with WPA failure due to encrypted EAPOL 2021-07-14 17:06:16 +02:00
fs f2fs: Prevent swap file in LFS mode 2021-07-14 17:06:13 +02:00
include tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing 2021-07-14 17:06:17 +02:00
init pid: take a reference when initializing cad_pid 2021-06-05 08:58:11 -07:00
ipc ipc/mqueue, msg, sem: avoid relying on a stack reference past its expiry 2021-05-22 15:09:07 -10:00
kernel tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing 2021-07-14 17:06:17 +02:00
lib iov_iter_fault_in_readable() should do nothing in xarray case 2021-07-14 17:06:07 +02:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -07:00
mm mm/gup: fix try_grab_compound_head() race with split_huge_page() 2021-07-14 17:06:12 +02:00
net SUNRPC: Should wake up the privileged task firstly. 2021-07-14 17:06:11 +02:00
samples VFIO fixes for v5.13-rc5 2021-06-03 11:52:24 -07:00
scripts recordmcount: Correct st_shndx handling 2021-06-18 09:09:17 -04:00
security trusted-keys: match tpm_get_ops on all return paths 2021-05-12 22:36:37 +03:00
sound ALSA: hda/realtek: fix mute led of the HP Pavilion 15-eh1xxx series 2021-07-14 17:06:04 +02:00
tools selftests/resctrl: Fix incorrect parsing of option "-t" 2021-07-14 17:06:16 +02:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: do not allow mapping valid but non-reference-counted pages 2021-06-24 11:55:11 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Marek's other e-mail address and identity without diacritics 2021-06-24 19:40:54 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge branch 'akpm' (patches from Andrew) 2021-06-25 11:05:03 -07:00
Makefile Linux 5.13.1 2021-07-07 08:24:58 -04:00
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.