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Stefan Berger 3fb0fa0864 fs: Pass AT_GETATTR_NOSEC flag to getattr interface function
[ Upstream commit 8a924db2d7 ]

When vfs_getattr_nosec() calls a filesystem's getattr interface function
then the 'nosec' should propagate into this function so that
vfs_getattr_nosec() can again be called from the filesystem's gettattr
rather than vfs_getattr(). The latter would add unnecessary security
checks that the initial vfs_getattr_nosec() call wanted to avoid.
Therefore, introduce the getattr flag GETATTR_NOSEC and allow to pass
with the new getattr_flags parameter to the getattr interface function.
In overlayfs and ecryptfs use this flag to determine which one of the
two functions to call.

In a recent code change introduced to IMA vfs_getattr_nosec() ended up
calling vfs_getattr() in overlayfs, which in turn called
security_inode_getattr() on an exiting process that did not have
current->fs set anymore, which then caused a kernel NULL pointer
dereference. With this change the call to security_inode_getattr() can
be avoided, thus avoiding the NULL pointer dereference.

Reported-by: <syzbot+a67fc5321ffb4b311c98@syzkaller.appspotmail.com>
Fixes: db1d1e8b98 ("IMA: use vfs_getattr_nosec to get the i_version")
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Tyler Hicks <code@tyhicks.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Suggested-by: Christian Brauner <brauner@kernel.org>
Co-developed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Link: https://lore.kernel.org/r/20231002125733.1251467-1-stefanb@linux.vnet.ibm.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-03 07:33:03 +01:00
arch x86/srso: Move retbleed IBPB check into existing 'has_microcode' code block 2023-11-28 17:20:16 +00:00
block blk-cgroup: avoid to warn !rcu_read_lock_held() in blkg_lookup() 2023-12-03 07:33:02 +01:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 17:19:42 +00:00
Documentation dt-bindings: timer: renesas,rz-mtu3: Fix overflow/underflow interrupt names 2023-11-28 17:20:02 +00:00
drivers drm/panel: auo,b101uan08.3: Fine tune the panel power sequence 2023-12-03 07:33:03 +01:00
fs fs: Pass AT_GETATTR_NOSEC flag to getattr interface function 2023-12-03 07:33:03 +01:00
include fs: Pass AT_GETATTR_NOSEC flag to getattr interface function 2023-12-03 07:33:03 +01:00
init proc: sysctl: prevent aliased sysctls from getting passed to init 2023-11-28 17:19:57 +00:00
io_uring io_uring/fdinfo: remove need for sqpoll lock for thread/pid retrieval 2023-11-28 17:19:52 +00:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel sched/fair: Fix the decision for load balance 2023-12-03 07:33:02 +01:00
lib lib/generic-radix-tree.c: Don't overflow in peek() 2023-11-28 17:19:35 +00:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: kmem: drop __GFP_NOFAIL when allocating objcg vectors 2023-11-28 17:20:13 +00:00
net rxrpc: Defer the response to a PING ACK until we've parsed it 2023-12-03 07:33:02 +01:00
rust rust: docs: fix logo replacement 2023-10-19 16:40:00 +02:00
samples samples/bpf: syscall_tp_user: Fix array out-of-bound access 2023-11-28 17:19:48 +00:00
scripts scripts/gdb/vmalloc: disable on no-MMU 2023-11-28 17:20:05 +00:00
security apparmor: Fix regression in mount mediation 2023-11-28 17:20:07 +00:00
sound ALSA: hda/realtek: Add quirks for HP Laptops 2023-11-28 17:20:10 +00:00
tools hv/hv_kvp_daemon: Some small fixes for handling NM keyfiles 2023-12-03 07:33:02 +01:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.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: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap 20 hotfixes. 12 are cc:stable and the remainder address post-6.5 issues 2023-10-24 09:52:16 -10:00
.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 USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
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 Char/Misc driver fixes for 6.6-final 2023-10-28 07:51:27 -10:00
Makefile Linux 6.6.3 2023-11-28 17:20:18 +00:00
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.