diff options
Diffstat (limited to 'kernel/auditsc.c')
| -rw-r--r-- | kernel/auditsc.c | 168 |
1 files changed, 127 insertions, 41 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index ae40ac8c39e72..1bd8827a01028 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -85,6 +85,9 @@ extern int audit_enabled; /* Indicates that audit should log the full pathname. */ #define AUDIT_NAME_FULL -1 +/* number of audit rules */ +int audit_n_rules; + /* 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). @@ -174,6 +177,7 @@ struct audit_aux_data_path { /* The per-task audit context. */ struct audit_context { + int dummy; /* must be the first element */ int in_syscall; /* 1 if task is in a syscall */ enum audit_state state; unsigned int serial; /* serial number for record */ @@ -205,6 +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. */ @@ -393,6 +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) @@ -514,7 +569,7 @@ static inline struct audit_context *audit_get_context(struct task_struct *tsk, context->return_valid = return_valid; context->return_code = return_code; - if (context->in_syscall && !context->auditable) { + if (context->in_syscall && !context->dummy && !context->auditable) { enum audit_state state; state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); @@ -530,17 +585,7 @@ static inline struct audit_context *audit_get_context(struct task_struct *tsk, } get_context: - context->pid = tsk->pid; - context->ppid = sys_getppid(); /* sic. tsk == current in all cases */ - context->uid = tsk->uid; - context->gid = tsk->gid; - context->euid = tsk->euid; - context->suid = tsk->suid; - context->fsuid = tsk->fsuid; - context->egid = tsk->egid; - context->sgid = tsk->sgid; - context->fsgid = tsk->fsgid; - context->personality = tsk->personality; + tsk->audit_context = NULL; return context; } @@ -749,6 +794,17 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts const char *tty; /* tsk == current */ + context->pid = tsk->pid; + context->ppid = sys_getppid(); /* sic. tsk == current in all cases */ + context->uid = tsk->uid; + context->gid = tsk->gid; + context->euid = tsk->euid; + context->suid = tsk->suid; + context->fsuid = tsk->fsuid; + context->egid = tsk->egid; + context->sgid = tsk->sgid; + context->fsgid = tsk->fsgid; + context->personality = tsk->personality; ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); if (!ab) @@ -1066,7 +1122,8 @@ void audit_syscall_entry(int arch, int major, context->argv[3] = a4; state = context->state; - if (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT) + context->dummy = !audit_n_rules; + if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT)) state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); if (likely(state == AUDIT_DISABLED)) return; @@ -1199,14 +1256,18 @@ void audit_putname(const char *name) #endif } -static void audit_inode_context(int idx, const struct inode *inode) +/* Copy inode data into an audit_names. */ +static void audit_copy_inode(struct audit_names *name, const struct inode *inode) { - struct audit_context *context = current->audit_context; - - selinux_get_inode_sid(inode, &context->names[idx].osid); + name->ino = inode->i_ino; + name->dev = inode->i_sb->s_dev; + name->mode = inode->i_mode; + name->uid = inode->i_uid; + name->gid = inode->i_gid; + name->rdev = inode->i_rdev; + selinux_get_inode_sid(inode, &name->osid); } - /** * audit_inode - store the inode and device from a lookup * @name: name being audited @@ -1240,20 +1301,14 @@ void __audit_inode(const char *name, const struct inode *inode) ++context->ino_count; #endif } - context->names[idx].ino = inode->i_ino; - context->names[idx].dev = inode->i_sb->s_dev; - context->names[idx].mode = inode->i_mode; - context->names[idx].uid = inode->i_uid; - context->names[idx].gid = inode->i_gid; - context->names[idx].rdev = inode->i_rdev; - audit_inode_context(idx, inode); + audit_copy_inode(&context->names[idx], inode); } /** * audit_inode_child - collect inode info for created/removed objects * @dname: inode's dentry name * @inode: inode being audited - * @pino: inode number of dentry parent + * @parent: inode of dentry parent * * For syscalls that create or remove filesystem objects, audit_inode * can only collect information for the filesystem object's parent. @@ -1264,7 +1319,7 @@ void __audit_inode(const char *name, const struct inode *inode) * unsuccessful attempts. */ void __audit_inode_child(const char *dname, const struct inode *inode, - unsigned long pino) + const struct inode *parent) { int idx; struct audit_context *context = current->audit_context; @@ -1278,7 +1333,7 @@ void __audit_inode_child(const char *dname, const struct inode *inode, if (!dname) goto update_context; for (idx = 0; idx < context->name_count; idx++) - if (context->names[idx].ino == pino) { + if (context->names[idx].ino == parent->i_ino) { const char *name = context->names[idx].name; if (!name) @@ -1302,16 +1357,47 @@ update_context: context->names[idx].name_len = AUDIT_NAME_FULL; context->names[idx].name_put = 0; /* don't call __putname() */ - if (inode) { - context->names[idx].ino = inode->i_ino; - context->names[idx].dev = inode->i_sb->s_dev; - context->names[idx].mode = inode->i_mode; - context->names[idx].uid = inode->i_uid; - context->names[idx].gid = inode->i_gid; - context->names[idx].rdev = inode->i_rdev; - audit_inode_context(idx, inode); - } else - context->names[idx].ino = (unsigned long)-1; + 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 AUDIT_DEBUG + context->ino_count++; +#endif + 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 (!context->in_syscall || !inode) + return; + + if (context->name_count == 0) { + context->name_count++; +#if AUDIT_DEBUG + context->ino_count++; +#endif + } + idx = context->name_count - 1; + + audit_copy_inode(&context->names[idx], inode); } /** @@ -1642,7 +1728,7 @@ int audit_bprm(struct linux_binprm *bprm) unsigned long p, next; void *to; - if (likely(!audit_enabled || !context)) + if (likely(!audit_enabled || !context || context->dummy)) return 0; ax = kmalloc(sizeof(*ax) + PAGE_SIZE * MAX_ARG_PAGES - bprm->p, @@ -1680,7 +1766,7 @@ int audit_socketcall(int nargs, unsigned long *args) struct audit_aux_data_socketcall *ax; struct audit_context *context = current->audit_context; - if (likely(!context)) + if (likely(!context || context->dummy)) return 0; ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL); @@ -1708,7 +1794,7 @@ int audit_sockaddr(int len, void *a) struct audit_aux_data_sockaddr *ax; struct audit_context *context = current->audit_context; - if (likely(!context)) + if (likely(!context || context->dummy)) return 0; ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL); |