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2020-12-16Merge tag 'selinux-pr-20201214' of ↵Linus Torvalds1-9/+17
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "While we have a small number of SELinux patches for v5.11, there are a few changes worth highlighting: - Change the LSM network hooks to pass flowi_common structs instead of the parent flowi struct as the LSMs do not currently need the full flowi struct and they do not have enough information to use it safely (missing information on the address family). This patch was discussed both with Herbert Xu (representing team netdev) and James Morris (representing team LSMs-other-than-SELinux). - Fix how we handle errors in inode_doinit_with_dentry() so that we attempt to properly label the inode on following lookups instead of continuing to treat it as unlabeled. - Tweak the kernel logic around allowx, auditallowx, and dontauditx SELinux policy statements such that the auditx/dontauditx are effective even without the allowx statement. Everything passes our test suite" * tag 'selinux-pr-20201214' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: lsm,selinux: pass flowi_common instead of flowi to the LSM hooks selinux: Fix fall-through warnings for Clang selinux: drop super_block backpointer from superblock_security_struct selinux: fix inode_doinit_with_dentry() LABEL_INVALID error handling selinux: allow dontauditx and auditallowx rules to take effect without allowx selinux: fix error initialization in inode_doinit_with_dentry()
2020-12-03security: add const qualifier to struct sock in various placesFlorian Westphal1-1/+1
A followup change to tcp_request_sock_op would have to drop the 'const' qualifier from the 'route_req' function as the 'security_inet_conn_request' call is moved there - and that function expects a 'struct sock *'. However, it turns out its also possible to add a const qualifier to security_inet_conn_request instead. Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-23lsm,selinux: pass flowi_common instead of flowi to the LSM hooksPaul Moore1-2/+2
As pointed out by Herbert in a recent related patch, the LSM hooks do not have the necessary address family information to use the flowi struct safely. As none of the LSMs currently use any of the protocol specific flowi information, replace the flowi pointers with pointers to the address family independent flowi_common struct. Reported-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-11-23selinux: Fix fall-through warnings for ClangGustavo A. R. Silva1-0/+1
In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning by explicitly adding a break statement instead of letting the code fall through to the next case. Link: https://github.com/KSPP/linux/issues/115 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-11-12selinux: drop super_block backpointer from superblock_security_structOndrej Mosnacek1-3/+2
It appears to have been needed for selinux_complete_init() in the past, but today it's useless. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-11-05selinux: fix inode_doinit_with_dentry() LABEL_INVALID error handlingPaul Moore1-18/+13
A previous fix, commit 83370b31a915 ("selinux: fix error initialization in inode_doinit_with_dentry()"), changed how failures were handled before a SELinux policy was loaded. Unfortunately that patch was potentially problematic for two reasons: it set the isec->initialized state without holding a lock, and it didn't set the inode's SELinux label to the "default" for the particular filesystem. The later can be a problem if/when a later attempt to revalidate the inode fails and SELinux reverts to the existing inode label. This patch should restore the default inode labeling that existed before the original fix, without affecting the LABEL_INVALID marking such that revalidation will still be attempted in the future. Fixes: 83370b31a915 ("selinux: fix error initialization in inode_doinit_with_dentry()") Reported-by: Sven Schnelle <svens@linux.ibm.com> Tested-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-10-27selinux: fix error initialization in inode_doinit_with_dentry()Tianyue Ren1-3/+16
Mark the inode security label as invalid if we cannot find a dentry so that we will retry later rather than marking it initialized with the unlabeled SID. Fixes: 9287aed2ad1f ("selinux: Convert isec->lock into a spinlock") Signed-off-by: Tianyue Ren <rentianyue@kylinos.cn> [PM: minor comment tweaks] Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-10-15Merge tag 'char-misc-5.10-rc1' of ↵Linus Torvalds1-3/+5
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of char, misc, and other assorted driver subsystem patches for 5.10-rc1. There's a lot of different things in here, all over the drivers/ directory. Some summaries: - soundwire driver updates - habanalabs driver updates - extcon driver updates - nitro_enclaves new driver - fsl-mc driver and core updates - mhi core and bus updates - nvmem driver updates - eeprom driver updates - binder driver updates and fixes - vbox minor bugfixes - fsi driver updates - w1 driver updates - coresight driver updates - interconnect driver updates - misc driver updates - other minor driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (396 commits) binder: fix UAF when releasing todo list docs: w1: w1_therm: Fix broken xref, mistakes, clarify text misc: Kconfig: fix a HISI_HIKEY_USB dependency LSM: Fix type of id parameter in kernel_post_load_data prototype misc: Kconfig: add a new dependency for HISI_HIKEY_USB firmware_loader: fix a kernel-doc markup w1: w1_therm: make w1_poll_completion static binder: simplify the return expression of binder_mmap test_firmware: Test partial read support firmware: Add request_partial_firmware_into_buf() firmware: Store opt_flags in fw_priv fs/kernel_file_read: Add "offset" arg for partial reads IMA: Add support for file reads without contents LSM: Add "contents" flag to kernel_read_file hook module: Call security_kernel_post_load_data() firmware_loader: Use security_post_load_data() LSM: Introduce kernel_post_load_data() hook fs/kernel_read_file: Add file_size output argument fs/kernel_read_file: Switch buffer size arg to size_t fs/kernel_read_file: Remove redundant size argument ...
2020-10-13Merge tag 'selinux-pr-20201012' of ↵Linus Torvalds1-7/+10
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "A decent number of SELinux patches for v5.10, twenty two in total. The highlights are listed below, but all of the patches pass our test suite and merge cleanly. - A number of changes to how the SELinux policy is loaded and managed inside the kernel with the goal of improving the atomicity of a SELinux policy load operation. These changes account for the bulk of the diffstat as well as the patch count. A special thanks to everyone who contributed patches and fixes for this work. - Convert the SELinux policy read-write lock to RCU. - A tracepoint was added for audited SELinux access control events; this should help provide a more unified backtrace across kernel and userspace. - Allow the removal of security.selinux xattrs when a SELinux policy is not loaded. - Enable policy capabilities in SELinux policies created with the scripts/selinux/mdp tool. - Provide some "no sooner than" dates for the SELinux checkreqprot sysfs deprecation" * tag 'selinux-pr-20201012' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: (22 commits) selinux: provide a "no sooner than" date for the checkreqprot removal selinux: Add helper functions to get and set checkreqprot selinux: access policycaps with READ_ONCE/WRITE_ONCE selinux: simplify away security_policydb_len() selinux: move policy mutex to selinux_state, use in lockdep checks selinux: fix error handling bugs in security_load_policy() selinux: convert policy read-write lock to RCU selinux: delete repeated words in comments selinux: add basic filtering for audit trace events selinux: add tracepoint on audited events selinux: Create new booleans and class dirs out of tree selinux: Standardize string literal usage for selinuxfs directory names selinux: Refactor selinuxfs directory populating functions selinux: Create function for selinuxfs directory cleanup selinux: permit removing security.selinux xattr before policy load selinux: fix memdup.cocci warnings selinux: avoid dereferencing the policy prior to initialization selinux: fix allocation failure check on newpolicy->sidtab selinux: refactor changing booleans selinux: move policy commit after updating selinuxfs ...
2020-10-05LSM: Add "contents" flag to kernel_read_file hookKees Cook1-2/+3
As with the kernel_load_data LSM hook, add a "contents" flag to the kernel_read_file LSM hook that indicates whether the LSM can expect a matching call to the kernel_post_read_file LSM hook with the full contents of the file. With the coming addition of partial file read support for kernel_read_file*() API, the LSM will no longer be able to always see the entire contents of a file during the read calls. For cases where the LSM must read examine the complete file contents, it will need to do so on its own every time the kernel_read_file hook is called with contents=false (or reject such cases). Adjust all existing LSMs to retain existing behavior. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Link: https://lore.kernel.org/r/20201002173828.2099543-12-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05LSM: Introduce kernel_post_load_data() hookKees Cook1-1/+1
There are a few places in the kernel where LSMs would like to have visibility into the contents of a kernel buffer that has been loaded or read. While security_kernel_post_read_file() (which includes the buffer) exists as a pairing for security_kernel_read_file(), no such hook exists to pair with security_kernel_load_data(). Earlier proposals for just using security_kernel_post_read_file() with a NULL file argument were rejected (i.e. "file" should always be valid for the security_..._file hooks, but it appears at least one case was left in the kernel during earlier refactoring. (This will be fixed in a subsequent patch.) Since not all cases of security_kernel_load_data() can have a single contiguous buffer made available to the LSM hook (e.g. kexec image segments are separately loaded), there needs to be a way for the LSM to reason about its expectations of the hook coverage. In order to handle this, add a "contents" argument to the "kernel_load_data" hook that indicates if the newly added "kernel_post_load_data" hook will be called with the full contents once loaded. That way, LSMs requiring full contents can choose to unilaterally reject "kernel_load_data" with contents=false (which is effectively the existing hook coverage), but when contents=true they can allow it and later evaluate the "kernel_post_load_data" hook once the buffer is loaded. With this change, LSMs can gain coverage over non-file-backed data loads (e.g. init_module(2) and firmware userspace helper), which will happen in subsequent patches. Additionally prepare IMA to start processing these cases. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: KP Singh <kpsingh@google.com> Link: https://lore.kernel.org/r/20201002173828.2099543-9-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05fs/kernel_read_file: Split into separate include fileScott Branden1-0/+1
Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h include file. That header gets pulled in just about everywhere and doesn't really need functions not related to the general fs interface. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-15selinux: Add helper functions to get and set checkreqprotLakshmi Ramasubramanian1-3/+3
checkreqprot data member in selinux_state struct is accessed directly by SELinux functions to get and set. This could cause unexpected read or write access to this data member due to compiler optimizations and/or compiler's reordering of access to this field. Add helper functions to get and set checkreqprot data member in selinux_state struct. These helper functions use READ_ONCE and WRITE_ONCE macros to ensure atomic read or write of memory for this data member. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com> Suggested-by: Paul Moore <paul@paul-moore.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-27selinux: move policy mutex to selinux_state, use in lockdep checksStephen Smalley1-0/+1
Move the mutex used to synchronize policy changes (reloads and setting of booleans) from selinux_fs_info to selinux_state and use it in lockdep checks for rcu_dereference_protected() calls in the security server functions. This makes the dependency on the mutex explicit in the code rather than relying on comments. Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-25selinux: convert policy read-write lock to RCUStephen Smalley1-1/+0
Convert the policy read-write lock to RCU. This is significantly simplified by the earlier work to encapsulate the policy data structures and refactor the policy load and boolean setting logic. Move the latest_granting sequence number into the selinux_policy structure so that it can be updated atomically with the policy. Since removing the policy rwlock and moving latest_granting reduces the selinux_ss structure to nothing more than a wrapper around the selinux_policy pointer, get rid of the extra layer of indirection. At present this change merely passes a hardcoded 1 to rcu_dereference_check() in the cases where we know we do not need to take rcu_read_lock(), with the preceding comment explaining why. Alternatively we could pass fsi->mutex down from selinuxfs and apply a lockdep check on it instead. Based in part on earlier attempts to convert the policy rwlock to RCU by Kaigai Kohei [1] and by Peter Enderborg [2]. [1] https://lore.kernel.org/selinux/6e2f9128-e191-ebb3-0e87-74bfccb0767f@tycho.nsa.gov/ [2] https://lore.kernel.org/selinux/20180530141104.28569-1-peter.enderborg@sony.com/ Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-24selinux: delete repeated words in commentsRandy Dunlap1-3/+3
Drop a repeated word in comments. {open, is, then} Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <stephen.smalley.work@gmail.com> Cc: Eric Paris <eparis@parisplace.org> Cc: selinux@vger.kernel.org Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: linux-security-module@vger.kernel.org [PM: fix subject line] Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-7/+1
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-20selinux: permit removing security.selinux xattr before policy loadStephen Smalley1-0/+3
Currently SELinux denies attempts to remove the security.selinux xattr always, even when permissive or no policy is loaded. This was originally motivated by the view that all files should be labeled, even if that label is unlabeled_t, and we shouldn't permit files that were once labeled to have their labels removed entirely. This however prevents removing SELinux xattrs in the case where one "disables" SELinux by not loading a policy (e.g. a system where runtime disable is removed and selinux=0 was not specified). Allow removing the xattr before SELinux is initialized. We could conceivably permit it even after initialization if permissive, or introduce a separate permission check here. Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-06-23selinux: allow reading labels before policy is loadedJonathan Lebon1-1/+6
This patch does for `getxattr` what commit 3e3e24b42043 ("selinux: allow labeling before policy is loaded") did for `setxattr`; it allows querying the current SELinux label on disk before the policy is loaded. One of the motivations described in that commit message also drives this patch: for Fedora CoreOS (and eventually RHEL CoreOS), we want to be able to move the root filesystem for example, from xfs to ext4 on RAID, on first boot, at initrd time.[1] Because such an operation works at the filesystem level, we need to be able to read the SELinux labels first from the original root, and apply them to the files of the new root. The previous commit enabled the second part of this process; this commit enables the first part. [1] https://github.com/coreos/fedora-coreos-tracker/issues/94 Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Jonathan Lebon <jlebon@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-06-13Merge tag 'notifications-20200601' of ↵Linus Torvalds1-7/+44
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull notification queue from David Howells: "This adds a general notification queue concept and adds an event source for keys/keyrings, such as linking and unlinking keys and changing their attributes. Thanks to Debarshi Ray, we do have a pull request to use this to fix a problem with gnome-online-accounts - as mentioned last time: https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47 Without this, g-o-a has to constantly poll a keyring-based kerberos cache to find out if kinit has changed anything. [ There are other notification pending: mount/sb fsinfo notifications for libmount that Karel Zak and Ian Kent have been working on, and Christian Brauner would like to use them in lxc, but let's see how this one works first ] LSM hooks are included: - A set of hooks are provided that allow an LSM to rule on whether or not a watch may be set. Each of these hooks takes a different "watched object" parameter, so they're not really shareable. The LSM should use current's credentials. [Wanted by SELinux & Smack] - A hook is provided to allow an LSM to rule on whether or not a particular message may be posted to a particular queue. This is given the credentials from the event generator (which may be the system) and the watch setter. [Wanted by Smack] I've provided SELinux and Smack with implementations of some of these hooks. WHY === Key/keyring notifications are desirable because if you have your kerberos tickets in a file/directory, your Gnome desktop will monitor that using something like fanotify and tell you if your credentials cache changes. However, we also have the ability to cache your kerberos tickets in the session, user or persistent keyring so that it isn't left around on disk across a reboot or logout. Keyrings, however, cannot currently be monitored asynchronously, so the desktop has to poll for it - not so good on a laptop. This facility will allow the desktop to avoid the need to poll. DESIGN DECISIONS ================ - The notification queue is built on top of a standard pipe. Messages are effectively spliced in. The pipe is opened with a special flag: pipe2(fds, O_NOTIFICATION_PIPE); The special flag has the same value as O_EXCL (which doesn't seem like it will ever be applicable in this context)[?]. It is given up front to make it a lot easier to prohibit splice&co from accessing the pipe. [?] Should this be done some other way? I'd rather not use up a new O_* flag if I can avoid it - should I add a pipe3() system call instead? The pipe is then configured:: ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth); ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter); Messages are then read out of the pipe using read(). - It should be possible to allow write() to insert data into the notification pipes too, but this is currently disabled as the kernel has to be able to insert messages into the pipe *without* holding pipe->mutex and the code to make this work needs careful auditing. - sendfile(), splice() and vmsplice() are disabled on notification pipes because of the pipe->mutex issue and also because they sometimes want to revert what they just did - but one or more notification messages might've been interleaved in the ring. - The kernel inserts messages with the wait queue spinlock held. This means that pipe_read() and pipe_write() have to take the spinlock to update the queue pointers. - Records in the buffer are binary, typed and have a length so that they can be of varying size. This allows multiple heterogeneous sources to share a common buffer; there are 16 million types available, of which I've used just a few, so there is scope for others to be used. Tags may be specified when a watchpoint is created to help distinguish the sources. - Records are filterable as types have up to 256 subtypes that can be individually filtered. Other filtration is also available. - Notification pipes don't interfere with each other; each may be bound to a different set of watches. Any particular notification will be copied to all the queues that are currently watching for it - and only those that are watching for it. - When recording a notification, the kernel will not sleep, but will rather mark a queue as having lost a message if there's insufficient space. read() will fabricate a loss notification message at an appropriate point later. - The notification pipe is created and then watchpoints are attached to it, using one of: keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01); watch_mount(AT_FDCWD, "/", 0, fd, 0x02); watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03); where in both cases, fd indicates the queue and the number after is a tag between 0 and 255. - Watches are removed if either the notification pipe is destroyed or the watched object is destroyed. In the latter case, a message will be generated indicating the enforced watch removal. Things I want to avoid: - Introducing features that make the core VFS dependent on the network stack or networking namespaces (ie. usage of netlink). - Dumping all this stuff into dmesg and having a daemon that sits there parsing the output and distributing it as this then puts the responsibility for security into userspace and makes handling namespaces tricky. Further, dmesg might not exist or might be inaccessible inside a container. - Letting users see events they shouldn't be able to see. TESTING AND MANPAGES ==================== - The keyutils tree has a pipe-watch branch that has keyctl commands for making use of notifications. Proposed manual pages can also be found on this branch, though a couple of them really need to go to the main manpages repository instead. If the kernel supports the watching of keys, then running "make test" on that branch will cause the testing infrastructure to spawn a monitoring process on the side that monitors a notifications pipe for all the key/keyring changes induced by the tests and they'll all be checked off to make sure they happened. https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch - A test program is provided (samples/watch_queue/watch_test) that can be used to monitor for keyrings, mount and superblock events. Information on the notifications is simply logged to stdout" * tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: smack: Implement the watch_key and post_notification hooks selinux: Implement the watch_key security hook keys: Make the KEY_NEED_* perms an enum rather than a mask pipe: Add notification lossage handling pipe: Allow buffers to be marked read-whole-or-error for notifications Add sample notification program watch_queue: Add a key/keyring notification facility security: Add hooks to rule on setting a watch pipe: Add general notification queue support pipe: Add O_NOTIFICATION_PIPE security: Add a hook for the point of notification insertion uapi: General notification queue definitions
2020-06-04Merge branch 'exec-linus' of ↵Linus Torvalds1-5/+3
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull execve updates from Eric Biederman: "Last cycle for the Nth time I ran into bugs and quality of implementation issues related to exec that could not be easily be fixed because of the way exec is implemented. So I have been digging into exec and cleanup up what I can. I don't think I have exec sorted out enough to fix the issues I started with but I have made some headway this cycle with 4 sets of changes. - promised cleanups after introducing exec_update_mutex - trivial cleanups for exec - control flow simplifications - remove the recomputation of bprm->cred The net result is code that is a bit easier to understand and work with and a decrease in the number of lines of code (if you don't count the added tests)" * 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (24 commits) exec: Compute file based creds only once exec: Add a per bprm->file version of per_clear binfmt_elf_fdpic: fix execfd build regression selftests/exec: Add binfmt_script regression test exec: Remove recursion from search_binary_handler exec: Generic execfd support exec/binfmt_script: Don't modify bprm->buf and then return -ENOEXEC exec: Move the call of prepare_binprm into search_binary_handler exec: Allow load_misc_binary to call prepare_binprm unconditionally exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds exec: Teach prepare_exec_creds how exec treats uids & gids exec: Set the point of no return sooner exec: Move handling of the point of no return to the top level exec: Run sync_mm_rss before taking exec_update_mutex exec: Fix spelling of search_binary_handler in a comment exec: Move the comment from above de_thread to above unshare_sighand exec: Rename flush_old_exec begin_new_exec exec: Move most of setup_new_exec into flush_old_exec exec: In setup_new_exec cache current in the local variable me ...
2020-05-20exec: Factor security_bprm_creds_for_exec out of security_bprm_set_credsEric W. Biederman1-5/+3
Today security_bprm_set_creds has several implementations: apparmor_bprm_set_creds, cap_bprm_set_creds, selinux_bprm_set_creds, smack_bprm_set_creds, and tomoyo_bprm_set_creds. Except for cap_bprm_set_creds they all test bprm->called_set_creds and return immediately if it is true. The function cap_bprm_set_creds ignores bprm->calld_sed_creds entirely. Create a new LSM hook security_bprm_creds_for_exec that is called just before prepare_binprm in __do_execve_file, resulting in a LSM hook that is called exactly once for the entire of exec. Modify the bits of security_bprm_set_creds that only want to be called once per exec into security_bprm_creds_for_exec, leaving only cap_bprm_set_creds behind. Remove bprm->called_set_creds all of it's former users have been moved to security_bprm_creds_for_exec. Add or upate comments a appropriate to bring them up to date and to reflect this change. Link: https://lkml.kernel.org/r/87v9kszrzh.fsf_-_@x220.int.ebiederm.org Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> # For the LSM and Smack bits Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-05-19selinux: Implement the watch_key security hookDavid Howells1-0/+14
Implement the watch_key security hook to make sure that a key grants the caller View permission in order to set a watch on a key. For the moment, the watch_devices security hook is left unimplemented as it's not obvious what the object should be since the queue is global and didn't previously exist. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: James Morris <jamorris@linux.microsoft.com>
2020-05-19keys: Make the KEY_NEED_* perms an enum rather than a maskDavid Howells1-7/+30
Since the meaning of combining the KEY_NEED_* constants is undefined, make it so that you can't do that by turning them into an enum. The enum is also given some extra values to represent special circumstances, such as: (1) The '0' value is reserved and causes a warning to trap the parameter being unset. (2) The key is to be unlinked and we require no permissions on it, only the keyring, (this replaces the KEY_LOOKUP_FOR_UNLINK flag). (3) An override due to CAP_SYS_ADMIN. (4) An override due to an instantiation token being present. (5) The permissions check is being deferred to later key_permission() calls. The extra values give the opportunity for LSMs to audit these situations. [Note: This really needs overhauling so that lookup_user_key() tells key_task_permission() and the LSM what operation is being done and leaves it to those functions to decide how to map that onto the available permits. However, I don't really want to make these change in the middle of the notifications patchset.] Signed-off-by: David Howells <dhowells@redhat.com> cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> cc: Paul Moore <paul@paul-moore.com> cc: Stephen Smalley <stephen.smalley.work@gmail.com> cc: Casey Schaufler <casey@schaufler-ca.com> cc: keyrings@vger.kernel.org cc: selinux@vger.kernel.org
2020-04-30Merge tag 'selinux-pr-20200430' of ↵Linus Torvalds1-25/+45
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull SELinux fixes from Paul Moore: "Two more SELinux patches to fix problems in the v5.7-rcX releases. Wei Yongjun's patch fixes a return code in an error path, and my patch fixes a problem where we were not correctly applying access controls to all of the netlink messages in the netlink_send LSM hook" * tag 'selinux-pr-20200430' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: properly handle multiple messages in selinux_netlink_send() selinux: fix error return code in cond_read_list()
2020-04-30selinux: properly handle multiple messages in selinux_netlink_send()Paul Moore1-25/+45
Fix the SELinux netlink_send hook to properly handle multiple netlink messages in a single sk_buff; each message is parsed and subject to SELinux access control. Prior to this patch, SELinux only inspected the first message in the sk_buff. Cc: stable@vger.kernel.org Reported-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-31Merge tag 'selinux-pr-20200330' of ↵Linus Torvalds1-2/+16
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull SELinux updates from Paul Moore: "We've got twenty SELinux patches for the v5.7 merge window, the highlights are below: - Deprecate setting /sys/fs/selinux/checkreqprot to 1. This flag was originally created to deal with legacy userspace and the READ_IMPLIES_EXEC personality flag. We changed the default from 1 to 0 back in Linux v4.4 and now we are taking the next step of deprecating it, at some point in the future we will take the final step of rejecting 1. - Allow kernfs symlinks to inherit the SELinux label of the parent directory. In order to preserve backwards compatibility this is protected by the genfs_seclabel_symlinks SELinux policy capability. - Optimize how we store filename transitions in the kernel, resulting in some significant improvements to policy load times. - Do a better job calculating our internal hash table sizes which resulted in additional policy load improvements and likely general SELinux performance improvements as well. - Remove the unused initial SIDs (labels) and improve how we handle initial SIDs. - Enable per-file labeling for the bpf filesystem. - Ensure that we properly label NFS v4.2 filesystems to avoid a temporary unlabeled condition. - Add some missing XFS quota command types to the SELinux quota access controls. - Fix a problem where we were not updating the seq_file position index correctly in selinuxfs. - We consolidate some duplicated code into helper functions. - A number of list to array conversions. - Update Stephen Smalley's email address in MAINTAINERS" * tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: clean up indentation issue with assignment statement NFS: Ensure security label is set for root inode MAINTAINERS: Update my email address selinux: avtab_init() and cond_policydb_init() return void selinux: clean up error path in policydb_init() selinux: remove unused initial SIDs and improve handling selinux: reduce the use of hard-coded hash sizes selinux: Add xfs quota command types selinux: optimize storage of filename transitions selinux: factor out loop body from filename_trans_read() security: selinux: allow per-file labeling for bpffs selinux: generalize evaluate_cond_node() selinux: convert cond_expr to array selinux: convert cond_av_list to array selinux: convert cond_list to array selinux: sel_avc_get_stat_idx should increase position index selinux: allow kernfs symlinks to inherit parent directory context selinux: simplify evaluate_cond_node() Documentation,selinux: deprecate setting checkreqprot to 1 selinux: move status variables out of selinux_ss
2020-02-22selinux: Add xfs quota command typesRichard Haines1-0/+7
Add Q_XQUOTAOFF, Q_XQUOTAON and Q_XSETQLIM to trigger filesystem quotamod permission check. Add Q_XGETQUOTA, Q_XGETQSTAT, Q_XGETQSTATV and Q_XGETNEXTQUOTA to trigger filesystem quotaget permission check. Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-11security: selinux: allow per-file labeling for bpffsConnor O'Brien1-0/+1
Add support for genfscon per-file labeling of bpffs files. This allows for separate permissions for different pinned bpf objects, which may be completely unrelated to each other. Signed-off-by: Connor O'Brien <connoro@google.com> Signed-off-by: Steven Moreland <smoreland@google.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10Merge tag 'selinux-pr-20200210' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull SELinux fixes from Paul Moore: "Two small fixes: one fixes a locking problem in the recently merged label translation code, the other fixes an embarrassing 'binderfs' / 'binder' filesystem name check" * tag 'selinux-pr-20200210' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: fix sidtab string cache locking selinux: fix typo in filesystem name
2020-02-10selinux: allow kernfs symlinks to inherit parent directory contextChristian Göttsche1-1/+3
Currently symlinks on kernel filesystems, like sysfs, are labeled on creation with the parent filesystem root sid. Allow symlinks to inherit the parent directory context, so fine-grained kernfs labeling can be applied to symlinks too and checking contexts doesn't complain about them. For backward-compatibility this behavior is contained in a new policy capability: genfs_seclabel_symlinks Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10Documentation,selinux: deprecate setting checkreqprot to 1Stephen Smalley1-1/+4
Deprecate setting the SELinux checkreqprot tunable to 1 via kernel parameter or /sys/fs/selinux/checkreqprot. Setting it to 0 is left intact for compatibility since Android and some Linux distributions do so for security and treat an inability to set it as a fatal error. Eventually setting it to 0 will become a no-op and the kernel will stop using checkreqprot's value internally altogether. checkreqprot was originally introduced as a compatibility mechanism for legacy userspace and the READ_IMPLIES_EXEC personality flag. However, if set to 1, it weakens security by allowing mappings to be made executable without authorization by policy. The default value for the SECURITY_SELINUX_CHECKREQPROT_VALUE config option was changed from 1 to 0 in commit 2a35d196c160e3 ("selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default") and both Android and Linux distributions began explicitly setting /sys/fs/selinux/checkreqprot to 0 some time ago. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-10selinux: move status variables out of selinux_ssOndrej Mosnacek1-0/+1
It fits more naturally in selinux_state, since it reflects also global state (the enforcing and policyload fields). Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-08Merge branch 'merge.nfs-fs_parse.1' of ↵Linus Torvalds1-8/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs file system parameter updates from Al Viro: "Saner fs_parser.c guts and data structures. The system-wide registry of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is the horror switch() in fs_parse() that would have to grow another case every time something got added to that system-wide registry. New syntax types can be added by filesystems easily now, and their namespace is that of functions - not of system-wide enum members. IOW, they can be shared or kept private and if some turn out to be widely useful, we can make them common library helpers, etc., without having to do anything whatsoever to fs_parse() itself. And we already get that kind of requests - the thing that finally pushed me into doing that was "oh, and let's add one for timeouts - things like 15s or 2h". If some filesystem really wants that, let them do it. Without somebody having to play gatekeeper for the variants blessed by direct support in fs_parse(), TYVM. Quite a bit of boilerplate is gone. And IMO the data structures make a lot more sense now. -200LoC, while we are at it" * 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits) tmpfs: switch to use of invalfc() cgroup1: switch to use of errorfc() et.al. procfs: switch to use of invalfc() hugetlbfs: switch to use of invalfc() cramfs: switch to use of errofc() et.al. gfs2: switch to use of errorfc() et.al. fuse: switch to use errorfc() et.al. ceph: use errorfc() and friends instead of spelling the prefix out prefix-handling analogues of errorf() and friends turn fs_param_is_... into functions fs_parse: handle optional arguments sanely fs_parse: fold fs_parameter_desc/fs_parameter_spec fs_parser: remove fs_parameter_description name field add prefix to fs_context->log ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log new primitive: __fs_parse() switch rbd and libceph to p_log-based primitives struct p_log, variants of warnf() et.al. taking that one instead teach logfc() to handle prefices, give it saner calling conventions get rid of cg_invalf() ...
2020-02-07fs_parse: fold fs_parameter_desc/fs_parameter_specAl Viro1-7/+3
The former contains nothing but a pointer to an array of the latter... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07fs_parser: remove fs_parameter_description name fieldEric Sandeen1-2/+1
Unused now. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-05selinux: fix typo in filesystem nameHridya Valsaraju1-1/+1
Correct the filesystem name to "binder" to enable genfscon per-file labelling for binderfs. Fixes: 7a4b5194747 ("selinux: allow per-file labelling for binderfs") Signed-off-by: Hridya Valsaraju <hridya@google.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: slight style changes to the subj/description] Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-20selinux: fix regression introduced by move_mount(2) syscallStephen Smalley1-0/+10
commit 2db154b3ea8e ("vfs: syscall: Add move_mount(2) to move mounts around") introduced a new move_mount(2) system call and a corresponding new LSM security_move_mount hook but did not implement this hook for any existing LSM. This creates a regression for SELinux with respect to consistent checking of mounts; the existing selinux_mount hook checks mounton permission to the mount point path. Provide a SELinux hook implementation for move_mount that applies this same check for consistency. In the future we may wish to add a new move_mount filesystem permission and check as well, but this addresses the immediate regression. Fixes: 2db154b3ea8e ("vfs: syscall: Add move_mount(2) to move mounts around") Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-16selinux: remove redundant allocation and helper functionsPaul Moore1-58/+36
This patch removes the inode, file, and superblock security blob allocation functions and moves the associated code into the respective LSM hooks. This patch also removes the inode_doinit() function as it was a trivial wrapper around inode_doinit_with_dentry() and called from one location in the code. Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-16selinux: remove redundant selinux_nlmsg_permHuaisheng Ye1-39/+34
selinux_nlmsg_perm is used for only by selinux_netlink_send. Remove the redundant function to simplify the code. Fix a typo by suggestion from Stephen. Signed-off-by: Huaisheng Ye <yehs1@lenovo.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10selinux: reorder hooks to make runtime disable less brokenOndrej Mosnacek1-31/+70
Commit b1d9e6b0646d ("LSM: Switch to lists of hooks") switched the LSM infrastructure to use per-hook lists, which meant that removing the hooks for a given module was no longer atomic. Even though the commit clearly documents that modules implementing runtime revmoval of hooks (only SELinux attempts this madness) need to take special precautions to avoid race conditions, SELinux has never addressed this. By inserting an artificial delay between the loop iterations of security_delete_hooks() (I used 100 ms), booting to a state where SELinux is enabled, but policy is not yet loaded, and running these commands: while true; do ping -c 1 <some IP>; done & echo -n 1 >/sys/fs/selinux/disable kill %1 wait ...I was able to trigger NULL pointer dereferences in various places. I also have a report of someone getting panics on a stock RHEL-8 kernel after setting SELINUX=disabled in /etc/selinux/config and rebooting (without adding "selinux=0" to kernel command-line). Reordering the SELinux hooks such that those that allocate structures are removed last seems to prevent these panics. It is very much possible that this doesn't make the runtime disable completely race-free, but at least it makes the operation much less fragile. Cc: stable@vger.kernel.org Fixes: b1d9e6b0646d ("LSM: Switch to lists of hooks") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10selinux: treat atomic flags more carefullyOndrej Mosnacek1-10/+11
The disabled/enforcing/initialized flags are all accessed concurrently by threads so use the appropriate accessors that ensure atomicity and document that it is expected. Use smp_load/acquire...() helpers (with memory barriers) for the initialized flag, since it gates access to the rest of the state structures. Note that the disabled flag is currently not used for anything other than avoiding double disable, but it will be used for bailing out of hooks once security_delete_hooks() is removed. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10selinux: make default_noexec read-only after initStephen Smalley1-1/+1
SELinux checks whether VM_EXEC is set in the VM_DATA_DEFAULT_FLAGS during initialization and saves the result in default_noexec for use in its mmap and mprotect hook function implementations to decide whether to apply EXECMEM, EXECHEAP, EXECSTACK, and EXECMOD checks. Mark default_noexec as ro_after_init to prevent later clearing it and thereby disabling these checks. It is only set legitimately from init code. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-10selinux: remove redundant msg_msg_alloc_securityHuaisheng Ye1-11/+6
selinux_msg_msg_alloc_security only calls msg_msg_alloc_security but do nothing else. And also msg_msg_alloc_security is just used by the former. Remove the redundant function to simplify the code. Signed-off-by: Huaisheng Ye <yehs1@lenovo.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-01-06selinux: allow per-file labelling for binderfsHridya Valsaraju1-0/+1
This patch allows genfscon per-file labeling for binderfs. This is required to have separate permissions to allow access to binder, hwbinder and vndbinder devices which are relocating to binderfs. Acked-by: Jeff Vander Stoep <jeffv@google.com> Acked-by: Mark Salyzyn <salyzyn@android.com> Signed-off-by: Hridya Valsaraju <hridya@google.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-18selinux: clean up selinux_enabled/disabled/enforcing_bootStephen Smalley1-7/+5
Rename selinux_enabled to selinux_enabled_boot to make it clear that it only reflects whether SELinux was enabled at boot. Replace the references to it in the MAC_STATUS audit log in sel_write_enforce() with hardcoded "1" values because this code is only reachable if SELinux is enabled and does not change its value, and update the corresponding MAC_STATUS audit log in sel_write_disable(). Stop clearing selinux_enabled in selinux_disable() since it is not used outside of initialization code that runs before selinux_disable() can be reached. Mark both selinux_enabled_boot and selinux_enforcing_boot as __initdata since they are only used in initialization code. Wrap the disabled field in the struct selinux_state with CONFIG_SECURITY_SELINUX_DISABLE since it is only used for runtime disable. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-12selinux: remove unnecessary selinux cred requestYang Guo1-4/+3
task_security_struct was obtained at the beginning of may_create and selinux_inode_init_security, no need to obtain again. may_create will be called very frequently when create dir and file. Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Yang Guo <guoyang2@huawei.com> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-09selinux: clean up selinux_inode_permission MAY_NOT_BLOCK testsStephen Smalley1-4/+4
Through a somewhat convoluted series of changes, we have ended up with multiple unnecessary occurrences of (flags & MAY_NOT_BLOCK) tests in selinux_inode_permission(). Clean it up and simplify. No functional change. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-09selinux: fall back to ref-walk if audit is requiredStephen Smalley1-4/+7
commit bda0be7ad994 ("security: make inode_follow_link RCU-walk aware") passed down the rcu flag to the SELinux AVC, but failed to adjust the test in slow_avc_audit() to also return -ECHILD on LSM_AUDIT_DATA_DENTRY. Previously, we only returned -ECHILD if generating an audit record with LSM_AUDIT_DATA_INODE since this was only relevant from inode_permission. Move the handling of MAY_NOT_BLOCK to avc_audit() and its inlined equivalent in selinux_inode_permission() immediately after we determine that audit is required, and always fall back to ref-walk in this case. Fixes: bda0be7ad994 ("security: make inode_follow_link RCU-walk aware") Reported-by: Will Deacon <will@kernel.org> Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-09selinux: revert "stop passing MAY_NOT_BLOCK to the AVC upon follow_link"Stephen Smalley1-2/+3
This reverts commit e46e01eebbbc ("selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link"). The correct fix is to instead fall back to ref-walk if audit is required irrespective of the specific audit data type. This is done in the next commit. Fixes: e46e01eebbbc ("selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link") Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-01 06:38:40 +0000