korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-15 00:04:15 +08:00
Code Issues Packages Projects Releases Wiki Activity
1,253,723 Commits 112 Branches 5,274 Tags 4.8 GiB
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%
8b48f0d28a
Go to file
Steven Rostedt (Google) 8b48f0d28a tracefs: Still use mount point as default permissions for instances 
commit 6599bd5517 upstream.

If the instances directory's permissions were never change, then have it
and its children use the mount point permissions as the default.

Currently, the permissions of instance directories are determined by the
instance directory's permissions itself. But if the tracefs file system is
remounted and changes the permissions, the instance directory and its
children should use the new permission.

But because both the instance directory and its children use the instance
directory's inode for permissions, it misses the update.

To demonstrate this:

  # cd /sys/kernel/tracing/
  # mkdir instances/foo
  # ls -ld instances/foo
 drwxr-x--- 5 root root 0 May  1 19:07 instances/foo
  # ls -ld instances
 drwxr-x--- 3 root root 0 May  1 18:57 instances
  # ls -ld current_tracer
 -rw-r----- 1 root root 0 May  1 18:57 current_tracer

  # mount -o remount,gid=1002 .
  # ls -ld instances
 drwxr-x--- 3 root root 0 May  1 18:57 instances
  # ls -ld instances/foo/
 drwxr-x--- 5 root root 0 May  1 19:07 instances/foo/
  # ls -ld current_tracer
 -rw-r----- 1 root lkp 0 May  1 18:57 current_tracer

Notice that changing the group id to that of "lkp" did not affect the
instances directory nor its children. It should have been:

  # ls -ld current_tracer
 -rw-r----- 1 root root 0 May  1 19:19 current_tracer
  # ls -ld instances/foo/
 drwxr-x--- 5 root root 0 May  1 19:25 instances/foo/
  # ls -ld instances
 drwxr-x--- 3 root root 0 May  1 19:19 instances

  # mount -o remount,gid=1002 .
  # ls -ld current_tracer
 -rw-r----- 1 root lkp 0 May  1 19:19 current_tracer
  # ls -ld instances
 drwxr-x--- 3 root lkp 0 May  1 19:19 instances
  # ls -ld instances/foo/
 drwxr-x--- 5 root lkp 0 May  1 19:25 instances/foo/

Where all files were updated by the remount gid update.

Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.686838327@goodmis.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-17 12:15:10 +02:00
arch x86/apic: Don't access the APIC when disabling x2APIC 2024-05-17 12:15:08 +02:00
block blk-iocost: do not WARN if iocg was already offlined 2024-05-17 12:14:50 +02:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto Revert "crypto: pkcs7 - remove sha1 support" 2024-04-03 15:32:31 +02:00
Documentation dt-bindings: iio: health: maxim,max30102: fix compatible check 2024-05-17 12:15:02 +02:00
drivers spi: microchip-core-qspi: fix setting spi bus clock rate 2024-05-17 12:15:09 +02:00
fs tracefs: Still use mount point as default permissions for instances 2024-05-17 12:15:10 +02:00
include kmsan: compiler_types: declare __no_sanitize_or_inline 2024-05-17 12:15:03 +02:00
init rust: make mutually exclusive with CFI_CLANG 2024-05-02 16:35:25 +02:00
io_uring io_uring: Fix io_cqring_wait() not restoring sigmask on get_timespec64() failure 2024-04-27 17:12:47 +02:00
ipc shm: Slim down dependencies 2023-12-20 19:26:31 -05:00
kernel workqueue: Fix selection of wake_cpu in kick_pool() 2024-05-17 12:15:02 +02:00
lib dyndbg: fix old BUG_ON in >control parser 2024-05-17 12:15:04 +02:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: use memalloc_nofs_save() in page_cache_ra_order() 2024-05-17 12:15:08 +02:00
net net: fix out-of-bounds access in ops_init 2024-05-17 12:15:07 +02:00
rust rust: macros: fix soundness issue in module! macro 2024-05-17 12:14:22 +02:00
samples work around gcc bugs with 'asm goto' with outputs 2024-02-09 15:57:48 -08:00
scripts kbuild: Disable KCSAN for autogenerated *.mod.c intermediaries 2024-05-17 12:14:39 +02:00
security selinux: avoid dereference of garbage after mount failure 2024-04-10 16:38:01 +02:00
sound ASoC: ti: davinci-mcasp: Fix race condition during probe 2024-05-17 12:15:04 +02:00
tools selftests/mm: fix powerpc ARCH check 2024-05-17 12:15:08 +02:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt KVM: Always flush async #PF workqueue when vCPU is being destroyed 2024-04-03 15:32:03 +02:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.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 Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.mailmap drm fixes for 6.8 final 2024-03-08 12:44:56 -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: supplement of zswap maintainers update 2024-01-25 23:52:21 -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 drm fixes for 6.8 final 2024-03-08 12:44:56 -08:00
Makefile Linux 6.8.9 2024-05-02 16:35:35 +02:00
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.