Scott Mayhew 459584258d selinux,smack: don't bypass permissions check in inode_setsecctx hook ... commit 76a0e79bc8 upstream. Marek Gresko reports that the root user on an NFS client is able to change the security labels on files on an NFS filesystem that is exported with root squashing enabled. The end of the kerneldoc comment for __vfs_setxattr_noperm() states: * This function requires the caller to lock the inode's i_mutex before it * is executed. It also assumes that the caller will make the appropriate * permission checks. nfsd_setattr() does do permissions checking via fh_verify() and nfsd_permission(), but those don't do all the same permissions checks that are done by security_inode_setxattr() and its related LSM hooks do. Since nfsd_setattr() is the only consumer of security_inode_setsecctx(), simplest solution appears to be to replace the call to __vfs_setxattr_noperm() with a call to __vfs_setxattr_locked(). This fixes the above issue and has the added benefit of causing nfsd to recall conflicting delegations on a file when a client tries to change its security label. Cc: stable@kernel.org Reported-by: Marek Gresko <marek.gresko@protonmail.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=218809 Signed-off-by: Scott Mayhew <smayhew@redhat.com> Tested-by: Stephen Smalley <stephen.smalley.work@gmail.com> Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2024-09-04 13:28:24 +02:00
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include	ima: Avoid blocking in RCU read-side critical section	2024-07-11 12:49:18 +02:00
ss	ima: Avoid blocking in RCU read-side critical section	2024-07-11 12:49:18 +02:00
.gitignore	.gitignore: add SPDX License Identifier	2020-03-25 11:50:48 +01:00
Kconfig	selinux: introduce SECURITY_SELINUX_DEBUG configuration	2023-07-20 16:21:52 -04:00
Makefile	selinux: fix Makefile for versions of make < v4.3	2023-06-02 15:34:29 -04:00
avc.c	selinux: add the processing of the failure of avc_add_xperms_decision()	2024-08-29 17:33:15 +02:00
hooks.c	selinux,smack: don't bypass permissions check in inode_setsecctx hook	2024-09-04 13:28:24 +02:00
ibpkey.c	selinux: stop passing selinux_state pointers and their offspring	2023-03-14 15:22:45 -04:00
ima.c	selinux: adjust typos in comments	2023-05-08 16:44:01 -04:00
netif.c	selinux: avoid implicit conversions in the netif code	2023-07-18 18:29:48 -04:00
netlabel.c	selinux: prevent KMSAN warning in selinux_inet_conn_request()	2023-08-15 18:23:22 -04:00
netlink.c	selinux: mark some global variables __ro_after_init	2021-01-12 10:08:55 -05:00
netnode.c	selinux: stop passing selinux_state pointers and their offspring	2023-03-14 15:22:45 -04:00
netport.c	selinux: stop passing selinux_state pointers and their offspring	2023-03-14 15:22:45 -04:00
nlmsgtab.c	selinux: use unsigned iterator in nlmsgtab code	2023-08-09 19:07:49 -04:00
selinuxfs.c	selinux: avoid dereference of garbage after mount failure	2024-04-10 16:35:48 +02:00
status.c	selinux: avoid implicit conversions regarding enforcing status	2023-07-18 18:29:50 -04:00
xfrm.c	selinux: de-brand SELinux	2023-07-18 18:42:57 -04:00