diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/audit.h | 1 | ||||
| -rw-r--r-- | kernel/auditfilter.c | 17 | ||||
| -rw-r--r-- | kernel/auditsc.c | 51 |
3 files changed, 69 insertions, 0 deletions
diff --git a/kernel/audit.h b/kernel/audit.h index 6aa33b848cf..a3370232a39 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -104,6 +104,7 @@ static inline int audit_hash_ino(u32 ino) return (ino & (AUDIT_INODE_BUCKETS-1)); } +extern int audit_match_class(int class, unsigned syscall); extern int audit_comparator(const u32 left, const u32 op, const u32 right); extern int audit_compare_dname_path(const char *dname, const char *path, int *dirlen); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index e4cafc11c51..a44879b0c72 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -302,6 +302,15 @@ int __init audit_register_class(int class, unsigned *list) return 0; } +int audit_match_class(int class, unsigned syscall) +{ + if (unlikely(syscall >= AUDIT_BITMASK_SIZE * sizeof(__u32))) + return 0; + if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) + return 0; + return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); +} + /* Common user-space to kernel rule translation. */ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) { @@ -414,6 +423,10 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) case AUDIT_ARG2: case AUDIT_ARG3: break; + case AUDIT_PERM: + if (f->val & ~15) + goto exit_free; + break; case AUDIT_INODE: err = audit_to_inode(&entry->rule, f); if (err) @@ -568,6 +581,10 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, entry->rule.buflen += f->val; entry->rule.filterkey = str; break; + case AUDIT_PERM: + if (f->val & ~15) + goto exit_free; + break; default: goto exit_free; } diff --git a/kernel/auditsc.c b/kernel/auditsc.c index efc1b74bebf..1bd8827a010 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -209,6 +209,54 @@ struct audit_context { #endif }; +#define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) +static inline int open_arg(int flags, int mask) +{ + int n = ACC_MODE(flags); + if (flags & (O_TRUNC | O_CREAT)) + n |= AUDIT_PERM_WRITE; + return n & mask; +} + +static int audit_match_perm(struct audit_context *ctx, int mask) +{ + unsigned n = ctx->major; + switch (audit_classify_syscall(ctx->arch, n)) { + case 0: /* native */ + if ((mask & AUDIT_PERM_WRITE) && + audit_match_class(AUDIT_CLASS_WRITE, n)) + return 1; + if ((mask & AUDIT_PERM_READ) && + audit_match_class(AUDIT_CLASS_READ, n)) + return 1; + if ((mask & AUDIT_PERM_ATTR) && + audit_match_class(AUDIT_CLASS_CHATTR, n)) + return 1; + return 0; + case 1: /* 32bit on biarch */ + if ((mask & AUDIT_PERM_WRITE) && + audit_match_class(AUDIT_CLASS_WRITE_32, n)) + return 1; + if ((mask & AUDIT_PERM_READ) && + audit_match_class(AUDIT_CLASS_READ_32, n)) + return 1; + if ((mask & AUDIT_PERM_ATTR) && + audit_match_class(AUDIT_CLASS_CHATTR_32, n)) + return 1; + return 0; + case 2: /* open */ + return mask & ACC_MODE(ctx->argv[1]); + case 3: /* openat */ + return mask & ACC_MODE(ctx->argv[2]); + case 4: /* socketcall */ + return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); + case 5: /* execve */ + return mask & AUDIT_PERM_EXEC; + default: + return 0; + } +} + /* Determine if any context name data matches a rule's watch data */ /* Compare a task_struct with an audit_rule. Return 1 on match, 0 * otherwise. */ @@ -397,6 +445,9 @@ static int audit_filter_rules(struct task_struct *tsk, /* ignore this field for filtering */ result = 1; break; + case AUDIT_PERM: + result = audit_match_perm(ctx, f->val); + break; } if (!result) |