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2021-03-08selinux: fix misspellings using codespell toolXiong Zhenwu1-1/+1
A typo is found out by codespell tool in 16th line of hashtab.c $ codespell ./security/selinux/ss/ ./hashtab.c:16: rouding ==> rounding Fix a typo found by codespell. Signed-off-by: Xiong Zhenwu <xiong.zhenwu@zte.com.cn> [PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-01-12selinux: mark some global variables __ro_after_initOndrej Mosnacek1-1/+1
All of these are never modified outside initcalls, so they can be __ro_after_init. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-17selinux: refactor changing booleansStephen Smalley1-0/+53
Refactor the logic for changing SELinux policy booleans in a similar manner to the refactoring of policy load, thereby reducing the size of the critical section when the policy write-lock is held and making it easier to convert the policy rwlock to RCU in the future. Instead of directly modifying the policydb in place, modify a copy and then swap it into place through a single pointer update. Only fully copy the portions of the policydb that are affected by boolean changes to avoid the full cost of a deep policydb copy. Introduce another level of indirection for the sidtab since changing booleans does not require updating the sidtab, unlike policy load. While we are here, create a common helper for notifying other kernel components and userspace of a policy change and call it from both security_set_bools() and selinux_policy_commit(). Based on an old (2004) patch by Kaigai Kohei [1] to convert the policy rwlock to RCU that was deferred at the time since it did not significantly improve performance and introduced complexity. Peter Enderborg later submitted a patch series to convert to RCU [2] that would have made changing booleans a much more expensive operation by requiring a full policydb_write();policydb_read(); sequence to deep copy the entire policydb and also had concerns regarding atomic allocations. This change is now simplified by the earlier work to encapsulate policy state in the selinux_policy struct and to refactor policy load. After this change, the last major obstacle to converting the policy rwlock to RCU is likely the sidtab live convert support. [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> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-07-09selinux: complete the inlining of hashtab functionsOndrej Mosnacek1-54/+5
Move (most of) the definitions of hashtab_search() and hashtab_insert() to the header file. In combination with the previous patch, this avoids calling the callbacks indirectly by function pointers and allows for better optimization, leading to a drastic performance improvement of these operations. With this patch, I measured a speed up in the following areas (measured on x86_64 F32 VM with 4 CPUs): 1. Policy load (`load_policy`) - takes ~150 ms instead of ~230 ms. 2. `chcon -R unconfined_u:object_r:user_tmp_t:s0:c381,c519 /tmp/linux-src` where /tmp/linux-src is an extracted linux-5.7 source tarball - takes ~522 ms instead of ~576 ms. This is because of many symtab_search() calls in string_to_context_struct() when there are many categories specified in the context. 3. `stress-ng --msg 1 --msg-ops 10000000` - takes 12.41 s instead of 13.95 s (consumes 18.6 s of kernel CPU time instead of 21.6 s). This is thanks to security_transition_sid() being ~43% faster after this patch. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-07-09selinux: prepare for inlining of hashtab functionsOndrej Mosnacek1-21/+23
Refactor searching and inserting into hashtabs to pave the way for converting hashtab_search() and hashtab_insert() to inline functions in the next patch. This will avoid indirect calls and allow the compiler to better optimize individual callers, leading to a significant performance improvement. In order to avoid the indirect calls, the key hashing and comparison callbacks need to be extracted from the hashtab struct and passed directly to hashtab_search()/_insert() by the callers so that the callback address is always known at compile time. The kernel's rhashtable library (<linux/rhashtable*.h>) does the same thing. This of course makes the hashtab functions slightly easier to misuse by passing a wrong callback set, but unfortunately there is no better way to implement a hash table that is both generic and efficient in C. This patch tries to somewhat mitigate this by only calling the hashtab functions in the same file where the corresponding callbacks are defined (wrapping them into more specialized functions as needed). Note that this patch doesn't bring any benefit without also moving the definitions of hashtab_search() and -_insert() to the header file, which is done in a follow-up patch for easier review of the hashtab.c changes in this patch. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-01selinux: do not allocate hashtabs dynamicallyOndrej Mosnacek1-36/+15
It is simpler to allocate them statically in the corresponding structure, avoiding unnecessary kmalloc() calls and pointer dereferencing. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> [PM: manual merging required in policydb.c] Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-27selinux: reduce the use of hard-coded hash sizesOndrej Mosnacek1-4/+24
Instead allocate hash tables with just the right size based on the actual number of elements (which is almost always known beforehand, we just need to defer the hashtab allocation to the right time). The only case when we don't know the size (with the current policy format) is the new filename transitions hashtable. Here I just left the existing value. After this patch, the time to load Fedora policy on x86_64 decreases from 790 ms to 167 ms. If the unconfined module is removed, it decreases from 750 ms to 122 ms. It is also likely that other operations are going to be faster, mainly string_to_context_struct() or mls_compute_sid(), but I didn't try to quantify that. The memory usage of all hash table arrays increases from ~58 KB to ~163 KB (with Fedora policy on x86_64). Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-03-01selinux: wrap global selinux stateStephen Smalley1-6/+2
Define a selinux state structure (struct selinux_state) for global SELinux state and pass it explicitly to all security server functions. The public portion of the structure contains state that is used throughout the SELinux code, such as the enforcing mode. The structure also contains a pointer to a selinux_ss structure whose definition is private to the security server and contains security server specific state such as the policy database and SID table. This change should have no effect on SELinux behavior or APIs (userspace or LSM). It merely wraps SELinux state and passes it explicitly as needed. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: minor fixups needed due to collisions with the SCTP patches] Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-11-15Merge tag 'selinux-pr-20171113' of ↵Linus Torvalds1-3/+16
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull SELinux updates from Paul Moore: "Seven SELinux patches for v4.15, although five of the seven are small build fixes and cleanups. Of the remaining two patches, the only one worth really calling out is Eric's fix for the SELinux filesystem xattr set/remove code; the other patch simply converts the SELinux hash table implementation to use kmem_cache. Eric's setxattr/removexattr tweak converts SELinux back to calling the commoncap implementations when the xattr is not SELinux related. The immediate win is to fixup filesystem capabilities in user namespaces, but it makes things a bit saner overall; more information in the commit description" * tag 'selinux-pr-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: remove extraneous initialization of slots_used and max_chain_len selinux: remove redundant assignment to len selinux: remove redundant assignment to str selinux: fix build warning selinux: fix build warning by removing the unused sid variable selinux: Perform both commoncap and selinux xattr checks selinux: Use kmem_cache for hashtab_node
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-16selinux: remove extraneous initialization of slots_used and max_chain_lenColin Ian King1-1/+1
Variables slots_used and max_chain_len are being initialized to zero twice. Remove the second set of initializations in the for loop. Cleans up the clang warnings: Value stored to 'slots_used' is never read Value stored to 'max_chain_len' is never read Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-09-20selinux: Use kmem_cache for hashtab_nodeKyeongdon Kim1-2/+15
During random test as own device to check slub account, we found some slack memory from hashtab_node(kmalloc-64). By using kzalloc(), middle of test result like below: allocated size 240768 request size 45144 slack size 195624 allocation count 3762 So, we want to use kmem_cache_zalloc() and that can reduce memory size 52byte(slack size/alloc count) per each struct. Signed-off-by: Kyeongdon Kim <kyeongdon.kim@lge.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-08-17selinux: update my email addressStephen Smalley1-1/+1
Update my email address since epoch.ncsc.mil no longer exists. MAINTAINERS and CREDITS are already correct. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-03-23selinux: Adjust four checks for null pointersMarkus Elfring1-4/+4
The script "checkpatch.pl" pointed information out like the following. Comparison to NULL could be written !… Thus fix affected source code places. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-03-23selinux: Use kmalloc_array() in hashtab_create()Markus Elfring1-1/+1
A multiplication for the size determination of a memory allocation indicated that an array data structure should be processed. Thus use the corresponding function "kmalloc_array". This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Paul Moore <paul@paul-moore.com>
2014-06-03selinux: conditionally reschedule in hashtab_insert while loading selinux policyDave Jones1-0/+3
After silencing the sleeping warning in mls_convert_context() I started seeing similar traces from hashtab_insert. Do a cond_resched there too. Signed-off-by: Dave Jones <davej@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <pmoore@redhat.com>
2008-08-15selinux: Unify for- and while-loop styleVesa-Matti Kari1-3/+3
Replace "thing != NULL" comparisons with just "thing" to make the code look more uniform (mixed styles were used even in the same source file). Signed-off-by: Vesa-Matti Kari <vmkari@cc.helsinki.fi> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-04-21SELinux: hashtab.c whitespace, syntax, and static declaraction cleanupsEric Paris1-2/+2
This patch changes hashtab.c to fix whitespace and syntax issues. Things that are fixed may include (does not not have to include) whitespace at end of lines spaces followed by tabs spaces used instead of tabs spacing around parenthesis locateion of { around struct and else clauses location of * in pointer declarations removal of initialization of static data to keep it in the right section useless {} in if statemetns useless checking for NULL before kfree fixing of the indentation depth of switch statements and any number of other things I forgot to mention Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2006-11-28SELinux: ensure keys constant in hashtab_searchChad Sellers1-3/+3
Makes the key argument passed into hashtab_search and all the functions it calls constant. These functions include hash table function pointers hash_value and keycmp. The only implementations of these currently are symhash and symcmp, which do not modify the key. The key parameter should never be changed by any of these, so it should be const. This is necessary to allow calling these functions with keys found in kernel object class and permission definitions. Signed-off-by: Chad Sellers <csellers@tresys.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2005-10-30[PATCH] SELinux: convert to kzallocJames Morris1-4/+2
This patch converts SELinux code from kmalloc/memset to the new kazalloc unction. On i386, this results in a text saving of over 1K. Before: text data bss dec hex filename 86319 4642 15236 106197 19ed5 security/selinux/built-in.o After: text data bss dec hex filename 85278 4642 15236 105156 19ac4 security/selinux/built-in.o Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+167
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!