Create a new audit record AUDIT_CONTAINER_ID to document the audit container identifier of a process if it is present. Called from audit_log_exit(), syscalls are covered. Include target_cid references from ptrace and signal. A sample raw event: time->Thu Nov 26 10:24:40 2020 type=PROCTITLE msg=audit(1606404280.226:174542): proctitle=2F7573722F62696E2F7065726C002D7700636F6E7461696E657269642F74657374 type=PATH msg=audit(1606404280.226:174542): item=1 name="/tmp/audit-testsuite-dir-8riQ/testsuite-1606404267-WNldVJCr" inode=428 dev=00:1f mode=0100644 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:user_tmp_t:s0 nametype=CREATE cap_fp=0 cap_fi=0 cap_fe=0 cap_fver=0 cap_frootid=0 type=PATH msg=audit(1606404280.226:174542): item=0 name="/tmp/audit-testsuite-dir-8riQ/" inode=427 dev=00:1f mode=040700 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:user_tmp_t:s0 nametype=PARENT cap_fp=0 cap_fi=0 cap_fe=0 cap_fver=0 cap_frootid=0 type=CWD msg=audit(1606404280.226:174542): cwd="/root/rgb/git/audit-testsuite/tests" type=SYSCALL msg=audit(1606404280.226:174542): arch=c000003e syscall=257 success=yes exit=6 a0=ffffff9c a1=557446bd5f10 a2=80241 a3=1b6 items=2 ppid=8724 pid=8758 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 ses=1 comm="perl" exe="/usr/bin/perl" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key="testsuite-1606404267-WNldVJCr" record=1 type=CONTAINER_ID msg=audit(1606404280.226:174542): record=1 contid=527940429489930240 Please see the github audit kernel issue for the main feature: https://github.com/linux-audit/audit-kernel/issues/90 Please see the github audit userspace issue for supporting additions: https://github.com/linux-audit/audit-userspace/issues/51 Please see the github audit testsuiite issue for the test case: https://github.com/linux-audit/audit-testsuite/issues/64 Please see the github audit wiki for the feature overview: https://github.com/linux-audit/audit-kernel/wiki/RFE-Audit-Container-ID Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx> --- Acks removed due to added "record=" field, track container of signalled process Acked-by: Serge Hallyn <serge@xxxxxxxxxx> Acked-by: Steve Grubb <sgrubb@xxxxxxxxxx> Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx> Reviewed-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx> --- include/uapi/linux/audit.h | 1 + kernel/audit.c | 74 ++++++++++++++++++++++++++++++++++++++ kernel/audit.h | 6 ++++ kernel/auditsc.c | 49 ++++++++++++++++++++----- 4 files changed, 122 insertions(+), 8 deletions(-) diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h index 26d65d0882e2..c56335e828dc 100644 --- a/include/uapi/linux/audit.h +++ b/include/uapi/linux/audit.h @@ -119,6 +119,7 @@ #define AUDIT_TIME_ADJNTPVAL 1333 /* NTP value adjustment */ #define AUDIT_BPF 1334 /* BPF subsystem */ #define AUDIT_EVENT_LISTENER 1335 /* Task joined multicast read socket */ +#define AUDIT_CONTAINER_ID 1336 /* Container ID */ #define AUDIT_AVC 1400 /* SE Linux avc denial or grant */ #define AUDIT_SELINUX_ERR 1401 /* Internal SE Linux Errors */ diff --git a/kernel/audit.c b/kernel/audit.c index fe94b295a362..5495b69bc505 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -319,6 +319,11 @@ static struct audit_contobj *_audit_contobj_get_bytask(struct task_struct *tsk) return _audit_contobj_get(info->cont); } +void *audit_contobj_get_bytask(struct task_struct *tsk) +{ + return (void *)_audit_contobj_get_bytask(tsk); +} + /* _audit_contobj_list_lock must be held by caller */ static void _audit_contobj_put(struct audit_contobj *cont) { @@ -331,6 +336,17 @@ static void _audit_contobj_put(struct audit_contobj *cont) } } +void audit_contobj_put(void **cont, int count) +{ + int i; + struct audit_contobj **contobj = (struct audit_contobj **)cont; + + spin_lock(&_audit_contobj_list_lock); + for (i = 0; i < count; i++) + _audit_contobj_put(contobj[i]); + spin_unlock(&_audit_contobj_list_lock); +} + static inline int audit_hash_contid(u64 contid) { return (contid & (AUDIT_CONTID_BUCKETS-1)); @@ -2327,6 +2343,59 @@ void audit_log_session_info(struct audit_buffer *ab) audit_log_format(ab, "auid=%u ses=%u", auid, sessionid); } +/* + * _audit_log_container_id - report container info + * @context: task or local context for record + * @cont: container object to report + * + * Returns 0 on record absence, positive integer on valid record id. + */ +static int _audit_log_container_id(struct audit_context *context, + struct audit_contobj *contobj) +{ + struct audit_buffer *ab; + int record; + + if (!contobj) + return 0; + /* Generate AUDIT_CONTAINER_ID record with container ID */ + ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONTAINER_ID); + if (!ab) + return 0; + audit_log_format(ab, "record=%d contid=%llu", + record = ++context->contid_records, contobj->id); + audit_log_end(ab); + return record; +} + +int audit_log_container_id(struct audit_context *context, void *cont) +{ + return _audit_log_container_id(context, (struct audit_contobj *)cont); +} + +/* + * audit_log_container_id_ctx - report container info + * @context: task or local context for record + * + * Returns 0 on record absence, positive integer on valid record id. + */ +int audit_log_container_id_ctx(struct audit_context *context) +{ + struct audit_contobj *contobj; + int record; + + rcu_read_lock(); + contobj = _audit_contobj_get_bytask(current); + rcu_read_unlock(); + if (!contobj) + return 0; + record = _audit_log_container_id(context, contobj); + spin_lock(&_audit_contobj_list_lock); + _audit_contobj_put(contobj); + spin_unlock(&_audit_contobj_list_lock); + return record; +} + void audit_log_key(struct audit_buffer *ab, char *key) { audit_log_format(ab, " key="); @@ -2631,6 +2700,11 @@ int audit_set_contid(struct task_struct *tsk, u64 contid) if (cont->id == contid) { /* task injection to existing container */ if (current == cont->owner) { + if (!refcount_read(&cont->refcount)) { + rc = -ENOTUNIQ; + spin_unlock(&_audit_contobj_list_lock); + goto error; + } _audit_contobj_get(cont); newcont = cont; } else { diff --git a/kernel/audit.h b/kernel/audit.h index c4a3d7e03fbe..de79f59d623f 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -135,6 +135,8 @@ struct audit_context { kuid_t target_uid; unsigned int target_sessionid; u32 target_sid; + void *target_cid; + int contid_records; char target_comm[TASK_COMM_LEN]; struct audit_tree_refs *trees, *first_trees; @@ -211,6 +213,10 @@ static inline int audit_hash_ino(u32 ino) } extern void audit_log_container_drop(void); +extern void *audit_contobj_get_bytask(struct task_struct *tsk); +extern void audit_contobj_put(void **cont, int count); +extern int audit_log_container_id(struct audit_context *context, void *cont); +extern int audit_log_container_id_ctx(struct audit_context *context); /* Indicates that audit should log the full pathname. */ #define AUDIT_NAME_FULL -1 diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 5056e32f9f47..2d9762f2f432 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -112,6 +112,7 @@ struct audit_aux_data_pids { kuid_t target_uid[AUDIT_AUX_PIDS]; unsigned int target_sessionid[AUDIT_AUX_PIDS]; u32 target_sid[AUDIT_AUX_PIDS]; + void *target_cid[AUDIT_AUX_PIDS]; char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; int pid_count; }; @@ -905,6 +906,7 @@ static inline void audit_free_names(struct audit_context *context) static inline void audit_free_aux(struct audit_context *context) { struct audit_aux_data *aux; + struct audit_aux_data_pids *axp; while ((aux = context->aux)) { context->aux = aux->next; @@ -912,6 +914,8 @@ static inline void audit_free_aux(struct audit_context *context) } while ((aux = context->aux_pids)) { context->aux_pids = aux->next; + axp = (struct audit_aux_data_pids *)aux; + audit_contobj_put(axp->target_cid, axp->pid_count); kfree(aux); } } @@ -985,7 +989,7 @@ static inline void audit_free_context(struct audit_context *context) static int audit_log_pid_context(struct audit_context *context, pid_t pid, kuid_t auid, kuid_t uid, unsigned int sessionid, - u32 sid, char *comm) + u32 sid, char *comm, int record) { struct audit_buffer *ab; char *ctx = NULL; @@ -1010,6 +1014,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid, } audit_log_format(ab, " ocomm="); audit_log_untrustedstring(ab, comm); + if (record) + audit_log_format(ab, " record=%d", record); audit_log_end(ab); return rc; @@ -1479,9 +1485,12 @@ static void audit_log_exit(void) struct audit_buffer *ab; struct audit_aux_data *aux; struct audit_names *n; + int record; context->personality = current->personality; + record = audit_log_container_id_ctx(context); + ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); if (!ab) return; /* audit_panic has been called */ @@ -1504,6 +1513,8 @@ static void audit_log_exit(void) audit_log_task_info(ab); audit_log_key(ab, context->filterkey); + if (record) + audit_log_format(ab, " record=%d", record); audit_log_end(ab); for (aux = context->aux; aux; aux = aux->next) { @@ -1562,22 +1573,28 @@ static void audit_log_exit(void) for (aux = context->aux_pids; aux; aux = aux->next) { struct audit_aux_data_pids *axs = (void *)aux; - for (i = 0; i < axs->pid_count; i++) + for (i = 0; i < axs->pid_count; i++) { + record = audit_log_container_id(context, axs->target_cid[i]); if (audit_log_pid_context(context, axs->target_pid[i], axs->target_auid[i], axs->target_uid[i], axs->target_sessionid[i], axs->target_sid[i], - axs->target_comm[i])) + axs->target_comm[i], record)) call_panic = 1; + } } - if (context->target_pid && - audit_log_pid_context(context, context->target_pid, - context->target_auid, context->target_uid, - context->target_sessionid, - context->target_sid, context->target_comm)) + if (context->target_pid) { + record = audit_log_container_id(context, context->target_cid); + if (audit_log_pid_context(context, context->target_pid, + context->target_auid, + context->target_uid, + context->target_sessionid, + context->target_sid, + context->target_comm, record)) call_panic = 1; + } if (context->pwd.dentry && context->pwd.mnt) { ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); @@ -1755,11 +1772,16 @@ void __audit_syscall_exit(int success, long return_code) audit_free_aux(context); context->aux = NULL; context->aux_pids = NULL; + if (context->target_pid) { + audit_contobj_put(&context->target_cid, 1); + context->target_cid = NULL; + } context->target_pid = 0; context->target_sid = 0; context->sockaddr_len = 0; context->type = 0; context->fds[0] = -1; + context->contid_records = 0; if (context->state != AUDIT_RECORD_CONTEXT) { kfree(context->filterkey); context->filterkey = NULL; @@ -2400,11 +2422,16 @@ void __audit_ptrace(struct task_struct *t) { struct audit_context *context = audit_context(); + if (context->target_pid) + audit_contobj_put(&context->target_cid, 1); context->target_pid = task_tgid_nr(t); context->target_auid = audit_get_loginuid(t); context->target_uid = task_uid(t); context->target_sessionid = audit_get_sessionid(t); security_task_getsecid(t, &context->target_sid); + rcu_read_lock(); + context->target_cid = audit_contobj_get_bytask(t); + rcu_read_unlock(); memcpy(context->target_comm, t->comm, TASK_COMM_LEN); } @@ -2432,6 +2459,9 @@ int audit_signal_info_syscall(struct task_struct *t) ctx->target_uid = t_uid; ctx->target_sessionid = audit_get_sessionid(t); security_task_getsecid(t, &ctx->target_sid); + rcu_read_lock(); + ctx->target_cid = audit_contobj_get_bytask(t); + rcu_read_unlock(); memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); return 0; } @@ -2453,6 +2483,9 @@ int audit_signal_info_syscall(struct task_struct *t) axp->target_uid[axp->pid_count] = t_uid; axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); security_task_getsecid(t, &axp->target_sid[axp->pid_count]); + rcu_read_lock(); + axp->target_cid[axp->pid_count] = audit_contobj_get_bytask(t); + rcu_read_unlock(); memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); axp->pid_count++; -- 2.18.4
