path: root/security/selinux/Kconfig
AgeCommit message (Collapse)Author
2020-02-10Documentation,selinux: deprecate setting checkreqprot to 1Stephen Smalley
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 <> Signed-off-by: Paul Moore <>
2020-01-07Documentation,selinux: fix references to old selinuxfs mount pointStephen Smalley
selinuxfs was originally mounted on /selinux, and various docs and kconfig help texts referred to nodes under it. In Linux 3.0, /sys/fs/selinux was introduced as the preferred mount point for selinuxfs. Fix all the old references to /selinux/ to /sys/fs/selinux/. While we are there, update the description of the selinux boot parameter to reflect the fact that the default value is always 1 since commit be6ec88f41ba94 ("selinux: Remove SECURITY_SELINUX_BOOTPARAM_VALUE") and drop discussion of runtime disable since it is deprecated. Signed-off-by: Stephen Smalley <> Signed-off-by: Paul Moore <>
2020-01-07selinux: deprecate disabling SELinux and runtimePaul Moore
Deprecate the CONFIG_SECURITY_SELINUX_DISABLE functionality. The code was originally developed to make it easier for Linux distributions to support architectures where adding parameters to the kernel command line was difficult. Unfortunately, supporting runtime disable meant we had to make some security trade-offs when it came to the LSM hooks, as documented in the Kconfig help text: NOTE: selecting this option will disable the '__ro_after_init' kernel hardening feature for security hooks. Please consider using the selinux=0 boot parameter instead of enabling this option. Fortunately it looks as if that the original motivation for the runtime disable functionality is gone, and Fedora/RHEL appears to be the only major distribution enabling this capability at build time so we are now taking steps to remove it entirely from the kernel. The first step is to mark the functionality as deprecated and print an error when it is used (what this patch is doing). As Fedora/RHEL makes progress in transitioning the distribution away from runtime disable, we will introduce follow-up patches over several kernel releases which will block for increasing periods of time when the runtime disable is used. Finally we will remove the option entirely once we believe all users have moved to the kernel cmdline approach. Acked-by: Casey Schaufler <> Acked-by: Ondrej Mosnacek <> Acked-by: Stephen Smalley <> Signed-off-by: Paul Moore <>
2019-12-09selinux: cache the SID -> context string translationOndrej Mosnacek
Translating a context struct to string can be quite slow, especially if the context has a lot of category bits set. This can cause quite noticeable performance impact in situations where the translation needs to be done repeatedly. A common example is a UNIX datagram socket with the SO_PASSSEC option enabled, which is used e.g. by systemd-journald when receiving log messages via datagram socket. This scenario can be reproduced with: cat /dev/urandom | base64 | logger & timeout 30s perf record -p $(pidof systemd-journald) -a -g kill %1 perf report -g none --pretty raw | grep security_secid_to_secctx Before the caching introduced by this patch, computing the context string (security_secid_to_secctx() function) takes up ~65% of systemd-journald's CPU time (assuming a context with 1024 categories set and Fedora x86_64 release kernel configs). After this patch (assuming near-perfect cache hit ratio) this overhead is reduced to just ~2%. This patch addresses the issue by caching a certain number (compile-time configurable) of recently used context strings to speed up repeated translations of the same context, while using only a small amount of memory. The cache is integrated into the existing sidtab table by adding a field to each entry, which when not NULL contains an RCU-protected pointer to a cache entry containing the cached string. The cache entries are kept in a linked list sorted according to how recently they were used. On a cache miss when the cache is full, the least recently used entry is removed to make space for the new entry. The patch migrates security_sid_to_context_core() to use the cache (also a few other functions where it was possible without too much fuss, but these mostly use the translation for logging in case of error, which is rare). Link: Cc: Michal Sekletar <> Signed-off-by: Ondrej Mosnacek <> Reviewed-by: Stephen Smalley <> Tested-by: Stephen Smalley <> Reviewed-by: Paul E. McKenney <> [PM: lots of merge fixups due to collisions with other sidtab patches] Signed-off-by: Paul Moore <>
2019-12-09selinux: sidtab reverse lookup hash tableJeff Vander Stoep
This replaces the reverse table lookup and reverse cache with a hashtable which improves cache-miss reverse-lookup times from O(n) to O(1)* and maintains the same performance as a reverse cache hit. This reduces the time needed to add a new sidtab entry from ~500us to 5us on a Pixel 3 when there are ~10,000 sidtab entries. The implementation uses the kernel's generic hashtable API, It uses the context's string represtation as the hash source, and the kernels generic string hashing algorithm full_name_hash() to reduce the string to a 32 bit value. This change also maintains the improvement introduced in commit ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve performance") which removed the need to keep the current sidtab locked during policy reload. It does however introduce periodic locking of the target sidtab while converting the hashtable. Sidtab entries are never modified or removed, so the context struct stored in the sid_to_context tree can also be used for the context_to_sid hashtable to reduce memory usage. This bug was reported by: - On the selinux bug tracker. BUG: kernel softlockup due to too many SIDs/contexts #37 - Jovana Knezevic on Android's bugtracker. Bug: 140252993 "During multi-user performance testing, we create and remove users many times. selinux_android_restorecon_pkgdir goes from 1ms to over 20ms after about 200 user creations and removals. Accumulated over ~280 packages, that adds a significant time to user creation, making perf benchmarks unreliable." * Hashtable lookup is only O(1) when n < the number of buckets. Signed-off-by: Jeff Vander Stoep <> Reported-by: Stephen Smalley <> Reported-by: Jovana Knezevic <> Reviewed-by: Stephen Smalley <> Tested-by: Stephen Smalley <> [PM: subj tweak, removed changelog from patch description] Signed-off-by: Paul Moore <>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <> Signed-off-by: Greg Kroah-Hartman <>
2019-01-08selinux: Remove SECURITY_SELINUX_BOOTPARAM_VALUEKees Cook
In preparation for removing CONFIG_DEFAULT_SECURITY, this removes the soon-to-be redundant SECURITY_SELINUX_BOOTPARAM_VALUE. Since explicit ordering via CONFIG_LSM or "lsm=" will define whether an LSM is enabled or not, this CONFIG will become effectively ignored, so remove it. However, in order to stay backward-compatible with "security=selinux", the enable variable defaults to true. Signed-off-by: Kees Cook <>
2017-03-06security: introduce CONFIG_SECURITY_WRITABLE_HOOKSJames Morris
Subsequent patches will add RO hardening to LSM hooks, however, SELinux still needs to be able to perform runtime disablement after init to handle architectures where init-time disablement via boot parameters is not feasible. Introduce a new kernel configuration parameter CONFIG_SECURITY_WRITABLE_HOOKS, and a helper macro __lsm_ro_after_init, to handle this case. Signed-off-by: James Morris <> Acked-by: Stephen Smalley <> Acked-by: Casey Schaufler <> Acked-by: Kees Cook <>
2016-08-18selinux: drop SECURITY_SELINUX_POLICYDB_VERSION_MAXWilliam Roberts
Remove the SECURITY_SELINUX_POLICYDB_VERSION_MAX Kconfig option Per: This was only needed on Fedora 3 and 4 and just causes issues now, so drop it. The MAX and MIN should just be whatever the kernel can support. Signed-off-by: William Roberts <> Signed-off-by: Paul Moore <>
2015-10-21selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE defaultPaul Moore
Change the SELinux checkreqprot default value to 0 so that SELinux performs access control checking on the actual memory protections used by the kernel and not those requested by the application. Signed-off-by: Paul Moore <>
2008-12-31selinux: Deprecate and schedule the removal of the the compat_net functionalityPaul Moore
This patch is the first step towards removing the old "compat_net" code from the kernel. Secmark, the "compat_net" replacement was first introduced in 2.6.18 (September 2006) and the major Linux distributions with SELinux support have transitioned to Secmark so it is time to start deprecating the "compat_net" mechanism. Testing a patched version of 2.6.28-rc6 with the initial release of Fedora Core 5 did not show any problems when running in enforcing mode. This patch adds an entry to the feature-removal-schedule.txt file and removes the SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT configuration option, forcing Secmark on by default although it can still be disabled at runtime. The patch also makes the Secmark permission checks "dynamic" in the sense that they are only executed when Secmark is configured; this should help prevent problems with older distributions that have not yet migrated to Secmark. Signed-off-by: Paul Moore <> Acked-by: James Morris <>
2008-09-12Update selinux info in MAINTAINERS and Kconfig help textStephen Smalley
Update the SELinux entry in MAINTAINERS and drop the obsolete information from the selinux Kconfig help text. Signed-off-by: Stephen Smalley <> Signed-off-by: James Morris <>
2008-04-18selinux: introduce permissive typesEric Paris
Introduce the concept of a permissive type. A new ebitmap is introduced to the policy database which indicates if a given type has the permissive bit set or not. This bit is tested for the scontext of any denial. The bit is meaningless on types which only appear as the target of a decision and never the source. A domain running with a permissive type will be allowed to perform any action similarly to when the system is globally set permissive. Signed-off-by: Eric Paris <> Acked-by: Stephen Smalley <> Signed-off-by: James Morris <>
2008-01-30SELinux: Add a capabilities bitmap to SELinux policy version 22Paul Moore
Add a new policy capabilities bitmap to SELinux policy version 22. This bitmap will enable the security server to query the policy to determine which features it supports. Signed-off-by: Paul Moore <> Signed-off-by: James Morris <>
2007-05-09Fix trivial typos in Kconfig* filesDavid Sterba
Fix several typos in help text in Kconfig* files. Signed-off-by: David Sterba <> Signed-off-by: Adrian Bunk <>
2006-10-03Still more typo fixesMatt LaPlante
Signed-off-by: Adrian Bunk <>
2006-10-03more misc typo fixesMatt LaPlante
Signed-off-by: Adrian Bunk <>
2006-09-26[PATCH] selinux: add support for range transitions on object classesDarrel Goeddel
Introduces support for policy version 21. This version of the binary kernel policy allows for defining range transitions on security classes other than the process security class. As always, backwards compatibility for older formats is retained. The security class is read in as specified when using the new format, while the "process" security class is assumed when using an older policy format. Signed-off-by: Darrel Goeddel <> Signed-off-by: Stephen Smalley <> Acked-by: James Morris <> Acked-by: Eric Paris <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
2006-09-26[PATCH] selinux: enable configuration of max policy versionStephen Smalley
Enable configuration of SELinux maximum supported policy version to support legacy userland (init) that does not gracefully handle kernels that support newer policy versions two or more beyond the installed policy, as in FC3 and FC4. [ improve Kconfig help text] Signed-off-by: Stephen Smalley <> Acked-by: James Morris <> Acked-by: Eric Paris <> Signed-off-by: Adrian Bunk <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
2006-06-17[SECMARK]: Add new packet controls to SELinuxJames Morris
Add new per-packet access controls to SELinux, replacing the old packet controls. Packets are labeled with the iptables SECMARK and CONNSECMARK targets, then security policy for the packets is enforced with these controls. To allow for a smooth transition to the new controls, the old code is still present, but not active by default. To restore previous behavior, the old controls may be activated at runtime by writing a '1' to /selinux/compat_net, and also via the kernel boot parameter selinux_compat_net. Switching between the network control models requires the security load_policy permission. The old controls will probably eventually be removed and any continued use is discouraged. With this patch, the new secmark controls for SElinux are disabled by default, so existing behavior is entirely preserved, and the user is not affected at all. It also provides a config option to enable the secmark controls by default (which can always be overridden at boot and runtime). It is also noted in the kconfig help that the user will need updated userspace if enabling secmark controls for SELinux and that they'll probably need the SECMARK and CONNMARK targets, and conntrack protocol helpers, although such decisions are beyond the scope of kernel configuration. Signed-off-by: James Morris <> Signed-off-by: Andrew Morton <> Signed-off-by: David S. Miller <>
2006-02-07[PATCH] selinux: require AUDITStephen Smalley
Make SELinux depend on AUDIT as it requires the basic audit support to log permission denials at all. Note that AUDITSYSCALL remains optional for SELinux, although it can be useful in providing further information upon denials. Signed-off-by: Stephen Smalley <> Acked-by: James Morris <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
2006-02-05[PATCH] selinux: require SECURITY_NETWORKStephen Smalley
Make SELinux depend on SECURITY_NETWORK (which depends on SECURITY), as it requires the socket hooks for proper operation even in the local case. Signed-off-by: Stephen Smalley <> Acked-by: James Morris <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!