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
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copy_up.c	v6.6-rc4.vfs.fixes	2023-09-26 08:50:30 -07:00
dir.c	ovl: store enum redirect_mode in config instead of a string	2023-06-19 14:02:01 +03:00
export.c	ovl: fix NULL pointer defer when encoding non-decodable lower fid	2023-10-03 09:24:11 +03:00
file.c	ovl: fix file reference leak when submitting aio	2023-10-02 13:08:31 +03:00
inode.c	fs: Pass AT_GETATTR_NOSEC flag to getattr interface function	2023-12-03 07:33:03 +01:00
Kconfig	ovl: Kconfig: introduce CONFIG_OVERLAY_FS_DEBUG	2023-08-12 19:02:53 +03:00
Makefile	ovl: modify layer parameter parsing	2023-06-20 14:10:40 +03:00
namei.c	ovl: make consistent use of OVL_FS()	2023-08-12 19:02:54 +03:00
overlayfs.h	fs: Pass AT_GETATTR_NOSEC flag to getattr interface function	2023-12-03 07:33:03 +01:00
ovl_entry.h	ovl: make use of ->layers safe in rcu pathwalk	2023-10-02 17:45:02 +03:00
params.c	ovl: temporarily disable appending lowedirs	2023-10-14 22:42:45 +03:00
params.h	ovl: move all parameter handling into params.{c,h}	2023-07-03 16:08:17 +03:00
readdir.c	vfs: get rid of old '->iterate' directory operation	2023-08-06 15:08:35 +02:00
super.c	ima: detect changes to the backing overlay file	2023-11-28 17:20:03 +00:00
util.c	overlayfs update for 6.6	2023-08-30 11:54:09 -07:00