diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/audit.h | 13 | ||||
| -rw-r--r-- | kernel/auditfilter.c | 48 | ||||
| -rw-r--r-- | kernel/auditsc.c | 311 | ||||
| -rw-r--r-- | kernel/ptrace.c | 3 | ||||
| -rw-r--r-- | kernel/signal.c | 10 |
5 files changed, 290 insertions, 95 deletions
diff --git a/kernel/audit.h b/kernel/audit.h index a3370232a39..815d6f5c04e 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -83,6 +83,7 @@ struct audit_krule { u32 field_count; char *filterkey; /* ties events to rules */ struct audit_field *fields; + struct audit_field *arch_f; /* quick access to arch field */ struct audit_field *inode_f; /* quick access to an inode field */ struct audit_watch *watch; /* associated watch */ struct list_head rlist; /* entry in audit_watch.rules list */ @@ -131,17 +132,19 @@ extern void audit_handle_ievent(struct inotify_watch *, u32, u32, u32, extern int selinux_audit_rule_update(void); #ifdef CONFIG_AUDITSYSCALL -extern void __audit_signal_info(int sig, struct task_struct *t); -static inline void audit_signal_info(int sig, struct task_struct *t) +extern int __audit_signal_info(int sig, struct task_struct *t); +static inline int audit_signal_info(int sig, struct task_struct *t) { - if (unlikely(audit_pid && t->tgid == audit_pid)) - __audit_signal_info(sig, t); + if (unlikely((audit_pid && t->tgid == audit_pid) || + (audit_signals && !audit_dummy_context()))) + return __audit_signal_info(sig, t); + return 0; } extern enum audit_state audit_filter_inodes(struct task_struct *, struct audit_context *); extern void audit_set_auditable(struct audit_context *); #else -#define audit_signal_info(s,t) +#define audit_signal_info(s,t) AUDIT_DISABLED #define audit_filter_inodes(t,c) AUDIT_DISABLED #define audit_set_auditable(c) #endif diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 3749193aed8..6c61263ff96 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -311,6 +311,43 @@ int audit_match_class(int class, unsigned syscall) return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); } +static inline int audit_match_class_bits(int class, u32 *mask) +{ + int i; + + if (classes[class]) { + for (i = 0; i < AUDIT_BITMASK_SIZE; i++) + if (mask[i] & classes[class][i]) + return 0; + } + return 1; +} + +static int audit_match_signal(struct audit_entry *entry) +{ + struct audit_field *arch = entry->rule.arch_f; + + if (!arch) { + /* When arch is unspecified, we must check both masks on biarch + * as syscall number alone is ambiguous. */ + return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, + entry->rule.mask) && + audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, + entry->rule.mask)); + } + + switch(audit_classify_arch(arch->val)) { + case 0: /* native */ + return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, + entry->rule.mask)); + case 1: /* 32bit on biarch */ + return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, + entry->rule.mask)); + default: + return 1; + } +} + /* Common user-space to kernel rule translation. */ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) { @@ -429,6 +466,7 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) err = -EINVAL; goto exit_free; } + entry->rule.arch_f = f; break; case AUDIT_PERM: if (f->val & ~15) @@ -519,7 +557,6 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, case AUDIT_FSGID: case AUDIT_LOGINUID: case AUDIT_PERS: - case AUDIT_ARCH: case AUDIT_MSGTYPE: case AUDIT_PPID: case AUDIT_DEVMAJOR: @@ -531,6 +568,9 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, case AUDIT_ARG2: case AUDIT_ARG3: break; + case AUDIT_ARCH: + entry->rule.arch_f = f; + break; case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: @@ -1221,6 +1261,9 @@ static inline int audit_add_rule(struct audit_entry *entry, #ifdef CONFIG_AUDITSYSCALL if (!dont_count) audit_n_rules++; + + if (!audit_match_signal(entry)) + audit_signals++; #endif mutex_unlock(&audit_filter_mutex); @@ -1294,6 +1337,9 @@ static inline int audit_del_rule(struct audit_entry *entry, #ifdef CONFIG_AUDITSYSCALL if (!dont_count) audit_n_rules--; + + if (!audit_match_signal(entry)) + audit_signals--; #endif mutex_unlock(&audit_filter_mutex); diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 628c7ac590a..e36481ed61b 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -78,17 +78,15 @@ extern int audit_enabled; * for saving names from getname(). */ #define AUDIT_NAMES 20 -/* AUDIT_NAMES_RESERVED is the number of slots we reserve in the - * audit_context from being used for nameless inodes from - * path_lookup. */ -#define AUDIT_NAMES_RESERVED 7 - /* Indicates that audit should log the full pathname. */ #define AUDIT_NAME_FULL -1 /* number of audit rules */ int audit_n_rules; +/* determines whether we collect data for signals sent */ +int audit_signals; + /* When fs/namei.c:getname() is called, we store the pointer in name and * we don't let putname() free it (instead we free all of the saved * pointers at syscall exit time). @@ -114,6 +112,9 @@ struct audit_aux_data { #define AUDIT_AUX_IPCPERM 0 +/* Number of target pids per aux struct. */ +#define AUDIT_AUX_PIDS 16 + struct audit_aux_data_mq_open { struct audit_aux_data d; int oflag; @@ -181,6 +182,13 @@ struct audit_aux_data_path { struct vfsmount *mnt; }; +struct audit_aux_data_pids { + struct audit_aux_data d; + pid_t target_pid[AUDIT_AUX_PIDS]; + u32 target_sid[AUDIT_AUX_PIDS]; + int pid_count; +}; + /* The per-task audit context. */ struct audit_context { int dummy; /* must be the first element */ @@ -201,6 +209,7 @@ struct audit_context { struct vfsmount * pwdmnt; struct audit_context *previous; /* For nested syscalls */ struct audit_aux_data *aux; + struct audit_aux_data *aux_pids; /* Save things to print about task_struct */ pid_t pid, ppid; @@ -209,6 +218,9 @@ struct audit_context { unsigned long personality; int arch; + pid_t target_pid; + u32 target_sid; + #if AUDIT_DEBUG int put_count; int ino_count; @@ -654,6 +666,10 @@ static inline void audit_free_aux(struct audit_context *context) context->aux = aux->next; kfree(aux); } + while ((aux = context->aux_pids)) { + context->aux_pids = aux->next; + kfree(aux); + } } static inline void audit_zero_context(struct audit_context *context, @@ -795,6 +811,29 @@ static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk audit_log_task_context(ab); } +static int audit_log_pid_context(struct audit_context *context, pid_t pid, + u32 sid) +{ + struct audit_buffer *ab; + char *s = NULL; + u32 len; + int rc = 0; + + ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); + if (!ab) + return 1; + + if (selinux_sid_to_string(sid, &s, &len)) { + audit_log_format(ab, "opid=%d obj=(none)", pid); + rc = 1; + } else + audit_log_format(ab, "opid=%d obj=%s", pid, s); + audit_log_end(ab); + kfree(s); + + return rc; +} + static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) { int i, call_panic = 0; @@ -973,6 +1012,21 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts audit_log_end(ab); } + for (aux = context->aux_pids; aux; aux = aux->next) { + struct audit_aux_data_pids *axs = (void *)aux; + int i; + + for (i = 0; i < axs->pid_count; i++) + if (audit_log_pid_context(context, axs->target_pid[i], + axs->target_sid[i])) + call_panic = 1; + } + + if (context->target_pid && + audit_log_pid_context(context, context->target_pid, + context->target_sid)) + call_panic = 1; + if (context->pwd && context->pwdmnt) { ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); if (ab) { @@ -1193,6 +1247,10 @@ void audit_syscall_exit(int valid, long return_code) } else { audit_free_names(context); audit_free_aux(context); + context->aux = NULL; + context->aux_pids = NULL; + context->target_pid = 0; + context->target_sid = 0; kfree(context->filterkey); context->filterkey = NULL; tsk->audit_context = context; @@ -1226,6 +1284,7 @@ void __audit_getname(const char *name) context->names[context->name_count].name_len = AUDIT_NAME_FULL; context->names[context->name_count].name_put = 1; context->names[context->name_count].ino = (unsigned long)-1; + context->names[context->name_count].osid = 0; ++context->name_count; if (!context->pwd) { read_lock(¤t->fs->lock); @@ -1279,6 +1338,28 @@ void audit_putname(const char *name) #endif } +static int audit_inc_name_count(struct audit_context *context, + const struct inode *inode) +{ + if (context->name_count >= AUDIT_NAMES) { + if (inode) + printk(KERN_DEBUG "name_count maxed, losing inode data: " + "dev=%02x:%02x, inode=%lu", + MAJOR(inode->i_sb->s_dev), + MINOR(inode->i_sb->s_dev), + inode->i_ino); + + else + printk(KERN_DEBUG "name_count maxed, losing inode data"); + return 1; + } + context->name_count++; +#if AUDIT_DEBUG + context->ino_count++; +#endif + return 0; +} + /* Copy inode data into an audit_names. */ static void audit_copy_inode(struct audit_names *name, const struct inode *inode) { @@ -1316,13 +1397,10 @@ void __audit_inode(const char *name, const struct inode *inode) else { /* FIXME: how much do we care about inodes that have no * associated name? */ - if (context->name_count >= AUDIT_NAMES - AUDIT_NAMES_RESERVED) + if (audit_inc_name_count(context, inode)) return; - idx = context->name_count++; + idx = context->name_count - 1; context->names[idx].name = NULL; -#if AUDIT_DEBUG - ++context->ino_count; -#endif } audit_copy_inode(&context->names[idx], inode); } @@ -1346,7 +1424,7 @@ void __audit_inode_child(const char *dname, const struct inode *inode, { int idx; struct audit_context *context = current->audit_context; - const char *found_name = NULL; + const char *found_parent = NULL, *found_child = NULL; int dirlen = 0; if (!context->in_syscall) @@ -1354,88 +1432,73 @@ void __audit_inode_child(const char *dname, const struct inode *inode, /* determine matching parent */ if (!dname) - goto update_context; - for (idx = 0; idx < context->name_count; idx++) - if (context->names[idx].ino == parent->i_ino) { - const char *name = context->names[idx].name; + goto add_names; - if (!name) - continue; + /* parent is more likely, look for it first */ + for (idx = 0; idx < context->name_count; idx++) { + struct audit_names *n = &context->names[idx]; - if (audit_compare_dname_path(dname, name, &dirlen) == 0) { - context->names[idx].name_len = dirlen; - found_name = name; - break; - } + if (!n->name) + continue; + + if (n->ino == parent->i_ino && + !audit_compare_dname_path(dname, n->name, &dirlen)) { + n->name_len = dirlen; /* update parent data in place */ + found_parent = n->name; + goto add_names; } + } -update_context: - idx = context->name_count; - if (context->name_count == AUDIT_NAMES) { - printk(KERN_DEBUG "name_count maxed and losing %s\n", - found_name ?: "(null)"); - return; + /* no matching parent, look for matching child */ + for (idx = 0; idx < context->name_count; idx++) { + struct audit_names *n = &context->names[idx]; + + if (!n->name) + continue; + + /* strcmp() is the more likely scenario */ + if (!strcmp(dname, n->name) || + !audit_compare_dname_path(dname, n->name, &dirlen)) { + if (inode) + audit_copy_inode(n, inode); + else + n->ino = (unsigned long)-1; + found_child = n->name; + goto add_names; + } } - context->name_count++; -#if AUDIT_DEBUG - context->ino_count++; -#endif - /* Re-use the name belonging to the slot for a matching parent directory. - * All names for this context are relinquished in audit_free_names() */ - context->names[idx].name = found_name; - context->names[idx].name_len = AUDIT_NAME_FULL; - context->names[idx].name_put = 0; /* don't call __putname() */ - - if (!inode) - context->names[idx].ino = (unsigned long)-1; - else - audit_copy_inode(&context->names[idx], inode); - - /* A parent was not found in audit_names, so copy the inode data for the - * provided parent. */ - if (!found_name) { - idx = context->name_count; - if (context->name_count == AUDIT_NAMES) { - printk(KERN_DEBUG - "name_count maxed and losing parent inode data: dev=%02x:%02x, inode=%lu", - MAJOR(parent->i_sb->s_dev), - MINOR(parent->i_sb->s_dev), - parent->i_ino); + +add_names: + if (!found_parent) { + if (audit_inc_name_count(context, parent)) return; - } - context->name_count++; -#if AUDIT_DEBUG - context->ino_count++; -#endif + idx = context->name_count - 1; + context->names[idx].name = NULL; audit_copy_inode(&context->names[idx], parent); } -} -/** - * audit_inode_update - update inode info for last collected name - * @inode: inode being audited - * - * When open() is called on an existing object with the O_CREAT flag, the inode - * data audit initially collects is incorrect. This additional hook ensures - * audit has the inode data for the actual object to be opened. - */ -void __audit_inode_update(const struct inode *inode) -{ - struct audit_context *context = current->audit_context; - int idx; + if (!found_child) { + if (audit_inc_name_count(context, inode)) + return; + idx = context->name_count - 1; - if (!context->in_syscall || !inode) - return; + /* Re-use the name belonging to the slot for a matching parent + * directory. All names for this context are relinquished in + * audit_free_names() */ + if (found_parent) { + context->names[idx].name = found_parent; + context->names[idx].name_len = AUDIT_NAME_FULL; + /* don't call __putname() */ + context->names[idx].name_put = 0; + } else { + context->names[idx].name = NULL; + } - if (context->name_count == 0) { - context->name_count++; -#if AUDIT_DEBUG - context->ino_count++; -#endif + if (inode) + audit_copy_inode(&context->names[idx], inode); + else + context->names[idx].ino = (unsigned long)-1; } - idx = context->name_count - 1; - - audit_copy_inode(&context->names[idx], inode); } /** @@ -1880,6 +1943,14 @@ int audit_sockaddr(int len, void *a) return 0; } +void __audit_ptrace(struct task_struct *t) +{ + struct audit_context *context = current->audit_context; + + context->target_pid = t->pid; + selinux_get_task_sid(t, &context->target_sid); +} + /** * audit_avc_path - record the granting or denial of permissions * @dentry: dentry to record @@ -1918,15 +1989,17 @@ int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt) * If the audit subsystem is being terminated, record the task (pid) * and uid that is doing that. */ -void __audit_signal_info(int sig, struct task_struct *t) +int __audit_signal_info(int sig, struct task_struct *t) { + struct audit_aux_data_pids *axp; + struct task_struct *tsk = current; + struct audit_context *ctx = tsk->audit_context; extern pid_t audit_sig_pid; extern uid_t audit_sig_uid; extern u32 audit_sig_sid; - if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) { - struct task_struct *tsk = current; - struct audit_context *ctx = tsk->audit_context; + if (audit_pid && t->tgid == audit_pid && + (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1)) { audit_sig_pid = tsk->pid; if (ctx) audit_sig_uid = ctx->loginuid; @@ -1934,4 +2007,72 @@ void __audit_signal_info(int sig, struct task_struct *t) audit_sig_uid = tsk->uid; selinux_get_task_sid(tsk, &audit_sig_sid); } + + if (!audit_signals) /* audit_context checked in wrapper */ + return 0; + + /* optimize the common case by putting first signal recipient directly + * in audit_context */ + if (!ctx->target_pid) { + ctx->target_pid = t->tgid; + selinux_get_task_sid(t, &ctx->target_sid); + return 0; + } + + axp = (void *)ctx->aux_pids; + if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { + axp = kzalloc(sizeof(*axp), GFP_ATOMIC); + if (!axp) + return -ENOMEM; + + axp->d.type = AUDIT_OBJ_PID; + axp->d.next = ctx->aux_pids; + ctx->aux_pids = (void *)axp; + } + BUG_ON(axp->pid_count > AUDIT_AUX_PIDS); + + axp->target_pid[axp->pid_count] = t->tgid; + selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]); + axp->pid_count++; + + return 0; +} + +/** + * audit_core_dumps - record information about processes that end abnormally + * @sig: signal value + * + * If a process ends with a core dump, something fishy is going on and we + * should record the event for investigation. + */ +void audit_core_dumps(long signr) +{ + struct audit_buffer *ab; + u32 sid; + + if (!audit_enabled) + return; + + if (signr == SIGQUIT) /* don't care for those */ + return; + + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); + audit_log_format(ab, "auid=%u uid=%u gid=%u", + audit_get_loginuid(current->audit_context), + current->uid, current->gid); + selinux_get_task_sid(current, &sid); + if (sid) { + char *ctx = NULL; + u32 len; + + if (selinux_sid_to_string(sid, &ctx, &len)) + audit_log_format(ab, " ssid=%u", sid); + else + audit_log_format(ab, " subj=%s", ctx); + kfree(ctx); + } + audit_log_format(ab, " pid=%d comm=", current->pid); + audit_log_untrustedstring(ab, current->comm); + audit_log_format(ab, " sig=%ld", signr); + audit_log_end(ab); } diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 4d50e06fd74..ad7949a589d 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -18,6 +18,7 @@ #include <linux/ptrace.h> #include <linux/security.h> #include <linux/signal.h> +#include <linux/audit.h> #include <asm/pgtable.h> #include <asm/uaccess.h> @@ -161,6 +162,8 @@ int ptrace_attach(struct task_struct *task) { int retval; + audit_ptrace(task); + retval = -EPERM; if (task->pid <= 1) goto out; diff --git a/kernel/signal.c b/kernel/signal.c index 34b7d6abce8..364fc95bf97 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -497,6 +497,11 @@ static int check_kill_permission(int sig, struct siginfo *info, int error = -EINVAL; if (!valid_signal(sig)) return error; + + error = audit_signal_info(sig, t); /* Let audit system see the signal */ + if (error) + return error; + error = -EPERM; if ((info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info))) && ((sig != SIGCONT) || @@ -506,10 +511,7 @@ static int check_kill_permission(int sig, struct siginfo *info, && !capable(CAP_KILL)) return error; - error = security_task_kill(t, info, sig, 0); - if (!error) - audit_signal_info(sig, t); /* Let audit system see the signal */ - return error; + return security_task_kill(t, info, sig, 0); } /* forward decl */ |