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2025-09-10audit: fix skb leak when audit rate limit is exceededGerald Yang
When configuring a small audit rate limit in /etc/audit/rules.d/audit.rules: -a always,exit -F arch=b64 -S openat -S truncate -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=4294967295 -k access -r 100 And then repeatedly triggering permission denied as a normal user: while :; do cat /proc/1/environ; done We can see the messages in kernel log: [ 2531.862184] audit: rate limit exceeded The unreclaimable slab objects start to leak quickly. With kmemleak enabled, many call traces appear like: unreferenced object 0xffff99144b13f600 (size 232): comm "cat", pid 1100, jiffies 4294739144 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 8540ec4f): kmemleak_alloc+0x4a/0x90 kmem_cache_alloc_node+0x2ea/0x390 __alloc_skb+0x174/0x1b0 audit_log_start+0x198/0x3d0 audit_log_proctitle+0x32/0x160 audit_log_exit+0x6c6/0x780 __audit_syscall_exit+0xee/0x140 syscall_exit_work+0x12b/0x150 syscall_exit_to_user_mode_prepare+0x39/0x80 syscall_exit_to_user_mode+0x11/0x260 do_syscall_64+0x8c/0x180 entry_SYSCALL_64_after_hwframe+0x78/0x80 This shows that the skb allocated in audit_log_start() and queued onto skb_list is never freed. In audit_log_end(), each skb is dequeued from skb_list and passed to __audit_log_end(). However, when the audit rate limit is exceeded, __audit_log_end() simply prints "rate limit exceeded" and returns without processing the skb. Since the skb is already removed from skb_list, audit_buffer_free() cannot free it later, leading to a memory leak. Fix this by freeing the skb when the rate limit is exceeded. Fixes: eb59d494eebd ("audit: add record for multiple task security contexts") Signed-off-by: Gerald Yang <gerald.yang@canonical.com> [PM: fixes tag, subj tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-09-04audit: init ab->skb_list earlier in audit_buffer_alloc()Eric Dumazet
syzbot found a bug in audit_buffer_alloc() if nlmsg_new() returns NULL. We need to initialize ab->skb_list before calling audit_buffer_free() which will use both the skb_list spinlock and list pointers. Fixes: eb59d494eebd ("audit: add record for multiple task security contexts") Reported-by: syzbot+bb185b018a51f8d91fd2@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/68b93e3c.a00a0220.eb3d.0000.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Eric Paris <eparis@redhat.com> Cc: audit@vger.kernel.org Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-08-30audit: add record for multiple object contextsCasey Schaufler
Create a new audit record AUDIT_MAC_OBJ_CONTEXTS. An example of the MAC_OBJ_CONTEXTS record is: type=MAC_OBJ_CONTEXTS msg=audit(1601152467.009:1050): obj_selinux=unconfined_u:object_r:user_home_t:s0 When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record the "obj=" field in other records in the event will be "obj=?". An AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has multiple security modules that may make access decisions based on an object security context. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subj tweak, audit example readability indents] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-08-30audit: add record for multiple task security contextsCasey Schaufler
Replace the single skb pointer in an audit_buffer with a list of skb pointers. Add the audit_stamp information to the audit_buffer as there's no guarantee that there will be an audit_context containing the stamp associated with the event. At audit_log_end() time create auxiliary records as have been added to the list. Functions are created to manage the skb list in the audit_buffer. Create a new audit record AUDIT_MAC_TASK_CONTEXTS. An example of the MAC_TASK_CONTEXTS record is: type=MAC_TASK_CONTEXTS msg=audit(1600880931.832:113) subj_apparmor=unconfined subj_smack=_ When an audit event includes a AUDIT_MAC_TASK_CONTEXTS record the "subj=" field in other records in the event will be "subj=?". An AUDIT_MAC_TASK_CONTEXTS record is supplied when the system has multiple security modules that may make access decisions based on a subject security context. Refactor audit_log_task_context(), creating a new audit_log_subj_ctx(). This is used in netlabel auditing to provide multiple subject security contexts as necessary. Suggested-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subj tweak, audit example readability indents] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-08-30lsm: security_lsmblob_to_secctx module selectionCasey Schaufler
Add a parameter lsmid to security_lsmblob_to_secctx() to identify which of the security modules that may be active should provide the security context. If the value of lsmid is LSM_ID_UNDEF the first LSM providing a hook is used. security_secid_to_secctx() is unchanged, and will always report the first LSM providing a hook. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subj tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-08-30audit: create audit_stamp structureCasey Schaufler
Replace the timestamp and serial number pair used in audit records with a structure containing the two elements. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subj tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-04-11audit: record AUDIT_ANOM_* events regardless of presence of rulesRichard Guy Briggs
When no audit rules are in place, AUDIT_ANOM_{LINK,CREAT} events reported in audit_log_path_denied() are unconditionally dropped due to an explicit check for the existence of any audit rules. Given this is a report of a security violation, allow it to be recorded regardless of the existence of any audit rules. To test, mkdir -p /root/tmp chmod 1777 /root/tmp touch /root/tmp/test.txt useradd test chown test /root/tmp/test.txt {echo C0644 12 test.txt; printf 'hello\ntest1\n'; printf \\000;} | \ scp -t /root/tmp Check with ausearch -m ANOM_CREAT -ts recent Link: https://issues.redhat.com/browse/RHEL-9065 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-04-11audit: mark audit_log_vformat() with __printf() attributeAndy Shevchenko
audit_log_vformat() is using printf() type of format, and GCC compiler (Debian 14.2.0-17) is not happy about this: kernel/audit.c:1978:9: error: function ‘audit_log_vformat’ might be a candidate for ‘gnu_printf’ format attribute kernel/audit.c:1987:17: error: function ‘audit_log_vformat’ might be a candidate for ‘gnu_printf’ format attribute Fix the compilation errors (`make W=1` when CONFIG_WERROR=y, which is default) by adding __printf() attribute. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [PM: commit description line wrap fixes] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-29audit: Initialize lsmctx to avoid memory allocation errorHuacai Chen
When audit is enabled in a kernel build, and there are no LSMs active that support LSM labeling, it is possible that local variable lsmctx in the AUDIT_SIGNAL_INFO handler in audit_receive_msg() could be used before it is properly initialize. Then kmalloc() will try to allocate a large amount of memory with the uninitialized length. This patch corrects this problem by initializing the lsmctx to a safe value when it is declared, which avoid errors like: WARNING: CPU: 2 PID: 443 at mm/page_alloc.c:4727 __alloc_pages_noprof ... ra: 9000000003059644 ___kmalloc_large_node+0x84/0x1e0 ERA: 900000000304d588 __alloc_pages_noprof+0x4c8/0x1040 CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) PRMD: 00000004 (PPLV0 +PIE -PWE) EUEN: 00000007 (+FPE +SXE +ASXE -BTE) ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7) ESTAT: 000c0000 [BRK] (IS= ECode=12 EsubCode=0) PRID: 0014c010 (Loongson-64bit, Loongson-3A5000) CPU: 2 UID: 0 PID: 443 Comm: auditd Not tainted 6.13.0-rc1+ #1899 ... Call Trace: [<9000000002def6a8>] show_stack+0x30/0x148 [<9000000002debf58>] dump_stack_lvl+0x68/0xa0 [<9000000002e0fe18>] __warn+0x80/0x108 [<900000000407486c>] report_bug+0x154/0x268 [<90000000040ad468>] do_bp+0x2a8/0x320 [<9000000002dedda0>] handle_bp+0x120/0x1c0 [<900000000304d588>] __alloc_pages_noprof+0x4c8/0x1040 [<9000000003059640>] ___kmalloc_large_node+0x80/0x1e0 [<9000000003061504>] __kmalloc_noprof+0x2c4/0x380 [<9000000002f0f7ac>] audit_receive_msg+0x764/0x1530 [<9000000002f1065c>] audit_receive+0xe4/0x1c0 [<9000000003e5abe8>] netlink_unicast+0x340/0x450 [<9000000003e5ae9c>] netlink_sendmsg+0x1a4/0x4a0 [<9000000003d9ffd0>] __sock_sendmsg+0x48/0x58 [<9000000003da32f0>] __sys_sendto+0x100/0x170 [<9000000003da3374>] sys_sendto+0x14/0x28 [<90000000040ad574>] do_syscall+0x94/0x138 [<9000000002ded318>] handle_syscall+0xb8/0x158 Fixes: 6fba89813ccf333d ("lsm: ensure the correct LSM context releaser") Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> [PM: resolved excessive line length in the backtrace] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-12-04lsm: replace context+len with lsm_contextCasey Schaufler
Replace the (secctx,seclen) pointer pair with a single lsm_context pointer to allow return of the LSM identifier along with the context and context length. This allows security_release_secctx() to know how to release the context. Callers have been modified to use or save the returned data from the new structure. security_secid_to_secctx() and security_lsmproc_to_secctx() will now return the length value on success instead of 0. Cc: netdev@vger.kernel.org Cc: audit@vger.kernel.org Cc: netfilter-devel@vger.kernel.org Cc: Todd Kjos <tkjos@google.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subject tweak, kdoc fix, signedness fix from Dan Carpenter] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-12-04lsm: ensure the correct LSM context releaserCasey Schaufler
Add a new lsm_context data structure to hold all the information about a "security context", including the string, its size and which LSM allocated the string. The allocation information is necessary because LSMs have different policies regarding the lifecycle of these strings. SELinux allocates and destroys them on each use, whereas Smack provides a pointer to an entry in a list that never goes away. Update security_release_secctx() to use the lsm_context instead of a (char *, len) pair. Change its callers to do likewise. The LSMs supporting this hook have had comments added to remind the developer that there is more work to be done. The BPF security module provides all LSM hooks. While there has yet to be a known instance of a BPF configuration that uses security contexts, the possibility is real. In the existing implementation there is potential for multiple frees in that case. Cc: linux-integrity@vger.kernel.org Cc: netdev@vger.kernel.org Cc: audit@vger.kernel.org Cc: netfilter-devel@vger.kernel.org To: Pablo Neira Ayuso <pablo@netfilter.org> Cc: linux-nfs@vger.kernel.org Cc: Todd Kjos <tkjos@google.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subject tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-11-18Merge tag 'lsm-pr-20241112' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm Pull lsm updates from Paul Moore: "Thirteen patches, all focused on moving away from the current 'secid' LSM identifier to a richer 'lsm_prop' structure. This move will help reduce the translation that is necessary in many LSMs, offering better performance, and make it easier to support different LSMs in the future" * tag 'lsm-pr-20241112' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: lsm: remove lsm_prop scaffolding netlabel,smack: use lsm_prop for audit data audit: change context data from secid to lsm_prop lsm: create new security_cred_getlsmprop LSM hook audit: use an lsm_prop in audit_names lsm: use lsm_prop in security_inode_getsecid lsm: use lsm_prop in security_current_getsecid audit: update shutdown LSM data lsm: use lsm_prop in security_ipc_getsecid audit: maintain an lsm_prop in audit_context lsm: add lsmprop_to_secctx hook lsm: use lsm_prop in security_audit_rule_match lsm: add the lsm_prop data structure
2024-10-11lsm: use lsm_prop in security_current_getsecidCasey Schaufler
Change the security_current_getsecid_subj() and security_task_getsecid_obj() interfaces to fill in a lsm_prop structure instead of a u32 secid. Audit interfaces will need to collect all possible security data for possible reporting. Cc: linux-integrity@vger.kernel.org Cc: audit@vger.kernel.org Cc: selinux@vger.kernel.org Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-10-11audit: update shutdown LSM dataCasey Schaufler
The audit process LSM information is changed from a secid audit_sig_sid to an lsm_prop in audit_sig_lsm. Update the users of this data appropriately. Calls to security_secid_to_secctx() are changed to use security_lsmprop_to_secctx() instead. security_current_getsecid_subj() is scaffolded. It will be updated in a subsequent patch. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> [PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-10-03audit: Reorganize kerneldoc parameter namesJulia Lawall
Reorganize kerneldoc parameter names to match the parameter order in the function header. Problems identified using Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-09-03audit: Make use of str_enabled_disabled() helperHongbo Li
Use str_enabled_disabled() helper instead of open coding the same. Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-08-28audit: use task_tgid_nr() instead of task_pid_nr()Ricardo Robaina
In a few audit records, PIDs were being recorded with task_pid_nr() instead of task_tgid_nr(). $ grep "task_pid_nr" kernel/audit*.c audit.c: task_pid_nr(current), auditfilter.c: pid = task_pid_nr(current); auditsc.c: audit_log_format(ab, " pid=%u", task_pid_nr(current)); For single-thread applications, the process id (pid) and the thread group id (tgid) are the same. However, on multi-thread applications, task_pid_nr() returns the current thread id (user-space's TID), while task_tgid_nr() returns the main thread id (user-space's PID). Since the users are more interested in the process id (pid), rather than the thread id (tid), this patch converts these callers to the correct method. Link: https://github.com/linux-audit/audit-kernel/issues/126 Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Ricardo Robaina <rrobaina@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-01-25audit: use KMEM_CACHE() instead of kmem_cache_create()Kunwu Chan
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create to simplify the creation of SLAB caches. Signed-off-by: Kunwu Chan <chentao@kylinos.cn> [PM: subject line tweaks] Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12audit: Send netlink ACK before setting connection in auditd_setChris Riches
When auditd_set sets the auditd_conn pointer, audit messages can immediately be put on the socket by other kernel threads. If the backlog is large or the rate is high, this can immediately fill the socket buffer. If the audit daemon requested an ACK for this operation, a full socket buffer causes the ACK to get dropped, also setting ENOBUFS on the socket. To avoid this race and ensure ACKs get through, fast-track the ACK in this specific case to ensure it is sent before auditd_conn is set. Signed-off-by: Chris Riches <chris.riches@nutanix.com> [PM: fix some tab vs space damage] Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-08-15audit: move trailing statements to next lineAtul Kumar Pant
Fixes following checkpatch.pl issue: ERROR: trailing statements should be on next line Signed-off-by: Atul Kumar Pant <atulpant.linux@gmail.com> [PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-07-20audit: include security.h unconditionallyXiu Jianfeng
The ifdef-else logic is already in the header file, so include it unconditionally, no functional changes here. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> [PM: fixed misspelling in the subject] Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-08-29audit: use time_after to compare timewuchi
Using time_{*} macro to compare time is better Signed-off-by: wuchi <wuchi.zero@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-13audit: make is_audit_feature_set() staticXiu Jianfeng
Currently nobody use is_audit_feature_set() outside this file, so make it static. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-07audit: remove redundant data_len checkShreenidhi Shedi
data_len is already getting checked if it's less than 2 earlier in this function. Signed-off-by: Shreenidhi Shedi <sshedi@vmware.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-01-25audit: improve audit queue handling when "audit=1" on cmdlinePaul Moore
When an admin enables audit at early boot via the "audit=1" kernel command line the audit queue behavior is slightly different; the audit subsystem goes to greater lengths to avoid dropping records, which unfortunately can result in problems when the audit daemon is forcibly stopped for an extended period of time. This patch makes a number of changes designed to improve the audit queuing behavior so that leaving the audit daemon in a stopped state for an extended period does not cause a significant impact to the system. - kauditd_send_queue() is now limited to looping through the passed queue only once per call. This not only prevents the function from looping indefinitely when records are returned to the current queue, it also allows any recovery handling in kauditd_thread() to take place when kauditd_send_queue() returns. - Transient netlink send errors seen as -EAGAIN now cause the record to be returned to the retry queue instead of going to the hold queue. The intention of the hold queue is to store, perhaps for an extended period of time, the events which led up to the audit daemon going offline. The retry queue remains a temporary queue intended to protect against transient issues between the kernel and the audit daemon. - The retry queue is now limited by the audit_backlog_limit setting, the same as the other queues. This allows admins to bound the size of all of the audit queues on the system. - kauditd_rehold_skb() now returns records to the end of the hold queue to ensure ordering is preserved in the face of recent changes to kauditd_send_queue(). Cc: stable@vger.kernel.org Fixes: 5b52330bbfe63 ("audit: fix auditd/kernel connection state tracking") Fixes: f4b3ee3c85551 ("audit: improve robustness of the audit queue handling") Reported-by: Gaosheng Cui <cuigaosheng1@huawei.com> Tested-by: Gaosheng Cui <cuigaosheng1@huawei.com> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-01-11Merge tag 'audit-pr-20220110' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "Four audit patches for v5.17: - Harden the code through additional use of the struct_size() macro and zero-length arrays to flexible-array conversions. - Ensure that processes which generate userspace audit records are not exempt from the kernel's audit throttling when the audit queues are being overrun" * tag 'audit-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: replace zero-length array with flexible-array member audit: use struct_size() helper in audit_[send|make]_reply() audit: ensure userspace is penalized the same as the kernel when under pressure audit: use struct_size() helper in kmalloc()
2022-01-11Merge tag 'selinux-pr-20220110' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "Nothing too significant, but five SELinux patches for v5.17 that do the following: - Harden the code through additional use of the struct_size() macro - Plug some memory leaks - Clean up the code via removal of the security_add_mnt_opt() LSM hook and minor tweaks to selinux_add_opt() - Rename security_task_getsecid_subj() to better reflect its actual behavior/use - now called security_current_getsecid_subj()" * tag 'selinux-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: minor tweaks to selinux_add_opt() selinux: fix potential memleak in selinux_add_opt() security,selinux: remove security_add_mnt_opt() selinux: Use struct_size() helper in kmalloc() lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()
2021-12-20audit: use struct_size() helper in audit_[send|make]_reply()Xiu Jianfeng
Make use of struct_size() helper instead of an open-coded calculation. Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-12-15audit: improve robustness of the audit queue handlingPaul Moore
If the audit daemon were ever to get stuck in a stopped state the kernel's kauditd_thread() could get blocked attempting to send audit records to the userspace audit daemon. With the kernel thread blocked it is possible that the audit queue could grow unbounded as certain audit record generating events must be exempt from the queue limits else the system enter a deadlock state. This patch resolves this problem by lowering the kernel thread's socket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks the kauditd_send_queue() function to better manage the various audit queues when connection problems occur between the kernel and the audit daemon. With this patch, the backlog may temporarily grow beyond the defined limits when the audit daemon is stopped and the system is under heavy audit pressure, but kauditd_thread() will continue to make progress and drain the queues as it would for other connection problems. For example, with the audit daemon put into a stopped state and the system configured to audit every syscall it was still possible to shutdown the system without a kernel panic, deadlock, etc.; granted, the system was slow to shutdown but that is to be expected given the extreme pressure of recording every syscall. The timeout value of HZ/10 was chosen primarily through experimentation and this developer's "gut feeling". There is likely no one perfect value, but as this scenario is limited in scope (root privileges would be needed to send SIGSTOP to the audit daemon), it is likely not worth exposing this as a tunable at present. This can always be done at a later date if it proves necessary. Cc: stable@vger.kernel.org Fixes: 5b52330bbfe63 ("audit: fix auditd/kernel connection state tracking") Reported-by: Gaosheng Cui <cuigaosheng1@huawei.com> Tested-by: Gaosheng Cui <cuigaosheng1@huawei.com> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-12-15audit: ensure userspace is penalized the same as the kernel when under pressurePaul Moore
Due to the audit control mutex necessary for serializing audit userspace messages we haven't been able to block/penalize userspace processes that attempt to send audit records while the system is under audit pressure. The result is that privileged userspace applications have a priority boost with respect to audit as they are not bound by the same audit queue throttling as the other tasks on the system. This patch attempts to restore some balance to the system when under audit pressure by blocking these privileged userspace tasks after they have finished their audit processing, and dropped the audit control mutex, but before they return to userspace. Reported-by: Gaosheng Cui <cuigaosheng1@huawei.com> Tested-by: Gaosheng Cui <cuigaosheng1@huawei.com> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-12-14audit: use struct_size() helper in kmalloc()Xiu Jianfeng
Make use of struct_size() helper instead of an open-coded calucation. Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-11-22lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()Paul Moore
The security_task_getsecid_subj() LSM hook invites misuse by allowing callers to specify a task even though the hook is only safe when the current task is referenced. Fix this by removing the task_struct argument to the hook, requiring LSM implementations to use the current task. While we are changing the hook declaration we also rename the function to security_current_getsecid_subj() in an effort to reinforce that the hook captures the subjective credentials of the current task and not an arbitrary task on the system. Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-03-22lsm: separate security_task_getsecid() into subjective and objective variantsPaul Moore
Of the three LSMs that implement the security_task_getsecid() LSM hook, all three LSMs provide the task's objective security credentials. This turns out to be unfortunate as most of the hook's callers seem to expect the task's subjective credentials, although a small handful of callers do correctly expect the objective credentials. This patch is the first step towards fixing the problem: it splits the existing security_task_getsecid() hook into two variants, one for the subjective creds, one for the objective creds. void security_task_getsecid_subj(struct task_struct *p, u32 *secid); void security_task_getsecid_obj(struct task_struct *p, u32 *secid); While this patch does fix all of the callers to use the correct variant, in order to keep this patch focused on the callers and to ease review, the LSMs continue to use the same implementation for both hooks. The net effect is that this patch should not change the behavior of the kernel in any way, it will be up to the latter LSM specific patches in this series to change the hook implementations and return the correct credentials. Acked-by: Mimi Zohar <zohar@linux.ibm.com> (IMA) Acked-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-01-15audit: Remove leftover reference to the audit_taskletDavidlohr Bueso
This was replaced with a kauditd_wait kthread long ago, back in: b7d1125817c (AUDIT: Send netlink messages from a separate kernel thread) Update the stale comment. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-01-04kernel/audit: convert comma to semicolonZheng Yongjun
Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-12-02audit: replace atomic_add_return()Yejune Deng
atomic_inc_return() is a little neater Signed-off-by: Yejune Deng <yejune.deng@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-11-24audit: fix macros warningsAlex Shi
Some unused macros could cause gcc warning: kernel/audit.c:68:0: warning: macro "AUDIT_UNINITIALIZED" is not used [-Wunused-macros] kernel/auditsc.c:104:0: warning: macro "AUDIT_AUX_IPCPERM" is not used [-Wunused-macros] kernel/auditsc.c:82:0: warning: macro "AUDITSC_INVALID" is not used [-Wunused-macros] AUDIT_UNINITIALIZED and AUDITSC_INVALID are still meaningful and should be in incorporated. Just remove AUDIT_AUX_IPCPERM. Thanks comments from Richard Guy Briggs and Paul Moore. Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Richard Guy Briggs <rgb@redhat.com> Cc: Eric Paris <eparis@redhat.com> Cc: linux-audit@redhat.com Cc: linux-kernel@vger.kernel.org Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-10-27audit: trigger accompanying records when no rules presentRichard Guy Briggs
When there are no audit rules registered, mandatory records (config, etc.) are missing their accompanying records (syscall, proctitle, etc.). This is due to audit context dummy set on syscall entry based on absence of rules that signals that no other records are to be printed. Clear the dummy bit if any record is generated, open coding this in audit_log_start(). The proctitle context and dummy checks are pointless since the proctitle record will not be printed if no syscall records are printed. The fds array is reset to -1 after the first syscall to indicate it isn't valid any more, but was never set to -1 when the context was allocated to indicate it wasn't yet valid. Check ctx->pwd in audit_log_name(). The audit_inode* functions can be called without going through getname_flags() or getname_kernel() that sets audit_names and cwd, so set the cwd in audit_alloc_name() if it has not already been done so due to audit_names being valid and purge all other audit_getcwd() calls. Revert the LSM dump_common_audit_data() LSM_AUDIT_DATA_* cases from the ghak96 patch since they are no longer necessary due to cwd coverage in audit_alloc_name(). Thanks to bauen1 <j2468h@googlemail.com> for reporting LSM situations in which context->cwd is not valid, inadvertantly fixed by the ghak96 patch. Please see upstream github issue https://github.com/linux-audit/audit-kernel/issues/120 This is also related to upstream github issue https://github.com/linux-audit/audit-kernel/issues/96 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-10-27audit: fix a kernel-doc markupMauro Carvalho Chehab
typo: kauditd_print_skb -> kauditd_printk_skb Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-26audit: Remove redundant null checkXu Wang
Because kfree_skb already checked NULL skb parameter, so the additional check is unnecessary, just remove it. Signed-off-by: Xu Wang <vulab@iscas.ac.cn> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-17audit: uninitialize variable audit_sig_sidJules Irenge
Checkpatch tool reports "ERROR: do not initialise globals/statics to 0" To fix this, audit_sig_sid is uninitialized As this is stored in the .bss section, the compiler can initialize the variable automatically. Signed-off-by: Jules Irenge <jbi.octave@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-17audit: change unnecessary globals into staticsJules Irenge
Variables sig_pid, audit_sig_uid and audit_sig_sid are only used in the audit.c file across the kernel Hence it appears no reason for declaring them as globals This patch removes their global declarations from the .h file and change them into static in the .c file. Signed-off-by: Jules Irenge <jbi.octave@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-08-04Merge tag 'audit-pr-20200803' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "Aside from some smaller bug fixes, here are the highlights: - add a new backlog wait metric to the audit status message, this is intended to help admins determine how long processes have been waiting for the audit backlog queue to clear - generate audit records for nftables configuration changes - generate CWD audit records for for the relevant LSM audit records" * tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: report audit wait metric in audit status reply audit: purge audit_log_string from the intra-kernel audit API audit: issue CWD record to accompany LSM_AUDIT_DATA_* records audit: use the proper gfp flags in the audit_log_nfcfg() calls audit: remove unused !CONFIG_AUDITSYSCALL __audit_inode* stubs audit: add gfp parameter to audit_log_nfcfg audit: log nftables configuration change events audit: Use struct_size() helper in alloc_chunk
2020-08-04Merge tag 'uninit-macro-v5.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull uninitialized_var() macro removal from Kees Cook: "This is long overdue, and has hidden too many bugs over the years. The series has several "by hand" fixes, and then a trivial treewide replacement. - Clean up non-trivial uses of uninitialized_var() - Update documentation and checkpatch for uninitialized_var() removal - Treewide removal of uninitialized_var()" * tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: compiler: Remove uninitialized_var() macro treewide: Remove uninitialized_var() usage checkpatch: Remove awareness of uninitialized_var() macro mm/debug_vm_pgtable: Remove uninitialized_var() usage f2fs: Eliminate usage of uninitialized_var() macro media: sur40: Remove uninitialized_var() usage KVM: PPC: Book3S PR: Remove uninitialized_var() usage clk: spear: Remove uninitialized_var() usage clk: st: Remove uninitialized_var() usage spi: davinci: Remove uninitialized_var() usage ide: Remove uninitialized_var() usage rtlwifi: rtl8192cu: Remove uninitialized_var() usage b43: Remove uninitialized_var() usage drbd: Remove uninitialized_var() usage x86/mm/numa: Remove uninitialized_var() usage docs: deprecated.rst: Add uninitialized_var()
2020-07-29Merge tag 'audit-pr-20200729' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit fixes from Paul Moore: "One small audit fix that you can hopefully merge before v5.8 is released. Unfortunately it is a revert of a patch that went in during the v5.7 window and we just recently started to see some bug reports relating to that commit. We are working on a proper fix, but I'm not yet clear on when that will be ready and we need to fix the v5.7 kernels anyway, so in the interest of time a revert seemed like the best solution right now" * tag 'audit-pr-20200729' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: revert: 1320a4052ea1 ("audit: trigger accompanying records when no rules present")
2020-07-29revert: 1320a4052ea1 ("audit: trigger accompanying records when no rules ↵Paul Moore
present") Unfortunately the commit listed in the subject line above failed to ensure that the task's audit_context was properly initialized/set before enabling the "accompanying records". Depending on the situation, the resulting audit_context could have invalid values in some of it's fields which could cause a kernel panic/oops when the task/syscall exists and the audit records are generated. We will revisit the original patch, with the necessary fixes, in a future kernel but right now we just want to fix the kernel panic with the least amount of added risk. Cc: stable@vger.kernel.org Fixes: 1320a4052ea1 ("audit: trigger accompanying records when no rules present") Reported-by: j2468h@googlemail.com Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-07-21audit: report audit wait metric in audit status replyMax Englander
In environments where the preservation of audit events and predictable usage of system memory are prioritized, admins may use a combination of --backlog_wait_time and -b options at the risk of degraded performance resulting from backlog waiting. In some cases, this risk may be preferred to lost events or unbounded memory usage. Ideally, this risk can be mitigated by making adjustments when backlog waiting is detected. However, detection can be difficult using the currently available metrics. For example, an admin attempting to debug degraded performance may falsely believe a full backlog indicates backlog waiting. It may turn out the backlog frequently fills up but drains quickly. To make it easier to reliably track degraded performance to backlog waiting, this patch makes the following changes: Add a new field backlog_wait_time_total to the audit status reply. Initialize this field to zero. Add to this field the total time spent by the current task on scheduled timeouts while the backlog limit is exceeded. Reset field to zero upon request via AUDIT_SET. Tested on Ubuntu 18.04 using complementary changes to the audit-userspace and audit-testsuite: - https://github.com/linux-audit/audit-userspace/pull/134 - https://github.com/linux-audit/audit-testsuite/pull/97 Signed-off-by: Max Englander <max.englander@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-07-21audit: purge audit_log_string from the intra-kernel audit APIRichard Guy Briggs
audit_log_string() was inteded to be an internal audit function and since there are only two internal uses, remove them. Purge all external uses of it by restructuring code to use an existing audit_log_format() or using audit_log_format(). Please see the upstream issue https://github.com/linux-audit/audit-kernel/issues/84 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-07-16treewide: Remove uninitialized_var() usageKees Cook
Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs Signed-off-by: Kees Cook <keescook@chromium.org>
2020-06-02Merge tag 'audit-pr-20200601' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "Summary of the significant patches: - Record information about binds/unbinds to the audit multicast socket. This helps identify which processes have/had access to the information in the audit stream. - Cleanup and add some additional information to the netfilter configuration events collected by audit. - Fix some of the audit error handling code so we don't leak network namespace references" * tag 'audit-pr-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: add subj creds to NETFILTER_CFG record to audit: Replace zero-length array with flexible-array audit: make symbol 'audit_nfcfgs' static netfilter: add audit table unregister actions audit: tidy and extend netfilter_cfg x_tables audit: log audit netlink multicast bind and unbind audit: fix a net reference leak in audit_list_rules_send() audit: fix a net reference leak in audit_send_reply()