Re: [PATCH v24 21/25] audit: add support for non-syscall auxiliary records

On 2021-01-26 08:41, Casey Schaufler wrote: > Standalone audit records have the timestamp and serial number generated > on the fly and as such are unique, making them standalone. This new > function audit_alloc_local() generates a local audit context that will > be used only for a standalone record and its auxiliary record(s). The > context is discarded immediately after the local associated records are > produced. > > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > Signed-off-by: Casey Schaufler <casey(a)schaufler-ca.com&gt; > Cc: linux-audit(a)redhat.com > To: Richard Guy Briggs <rgb(a)redhat.com&gt; This has been minorly bothering me for several revisions... Is there a way for the development/authorship to be accurately reflected if/when this patch is merged before the contid patch set?

> --- > include/linux/audit.h | 8 ++++++++ > kernel/audit.h | 1 + > kernel/auditsc.c | 33 ++++++++++++++++++++++++++++----- > 3 files changed, 37 insertions(+), 5 deletions(-) > > diff --git a/include/linux/audit.h b/include/linux/audit.h > index 418a485af114..97cd7471e572 100644 > --- a/include/linux/audit.h > +++ b/include/linux/audit.h > @@ -289,6 +289,8 @@ static inline int audit_signal_info(int sig, struct task_struct *t) > /* Public API */ > extern int audit_alloc(struct task_struct *task); > extern void __audit_free(struct task_struct *task); > +extern struct audit_context *audit_alloc_local(gfp_t gfpflags); > +extern void audit_free_context(struct audit_context *context); > extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1, > unsigned long a2, unsigned long a3); > extern void __audit_syscall_exit(int ret_success, long ret_value); > @@ -552,6 +554,12 @@ static inline void audit_log_nfcfg(const char *name, u8 af, > extern int audit_n_rules; > extern int audit_signals; > #else /* CONFIG_AUDITSYSCALL */ > ++static inline struct audit_context *audit_alloc_local(gfp_t gfpflags) > +{ > + return NULL; > +} > +static inline void audit_free_context(struct audit_context *context) > +{ } > static inline int audit_alloc(struct task_struct *task) > { > return 0; > diff --git a/kernel/audit.h b/kernel/audit.h > index ce41886807bb..3f2285e1c6e0 100644 > --- a/kernel/audit.h > +++ b/kernel/audit.h > @@ -99,6 +99,7 @@ struct audit_proctitle { > struct audit_context { > int dummy; /* must be the first element */ > int in_syscall; /* 1 if task is in a syscall */ > + bool local; /* local context needed */ > enum audit_state state, current_state; > unsigned int serial; /* serial number for record */ > int major; /* syscall number */ > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index de2b2ecb3aea..479b3933d788 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -927,11 +927,13 @@ static inline void audit_free_aux(struct audit_context *context) > } > } > > -static inline struct audit_context *audit_alloc_context(enum audit_state state) > +static inline struct audit_context *audit_alloc_context(enum audit_state state, > + gfp_t gfpflags) > { > struct audit_context *context; > > - context = kzalloc(sizeof(*context), GFP_KERNEL); > + /* We can be called in atomic context via audit_tg() */ > + context = kzalloc(sizeof(*context), gfpflags); > if (!context) > return NULL; > context->state = state; > @@ -967,7 +969,8 @@ int audit_alloc(struct task_struct *tsk) > return 0; > } > > - if (!(context = audit_alloc_context(state))) { > + context = audit_alloc_context(state, GFP_KERNEL); > + if (!context) { > kfree(key); > audit_log_lost("out of memory in audit_alloc"); > return -ENOMEM; > @@ -979,8 +982,27 @@ int audit_alloc(struct task_struct *tsk) > return 0; > } > > -static inline void audit_free_context(struct audit_context *context) > +struct audit_context *audit_alloc_local(gfp_t gfpflags) > { > + struct audit_context *context = NULL; > + > + context = audit_alloc_context(AUDIT_RECORD_CONTEXT, gfpflags); > + if (!context) { > + audit_log_lost("out of memory in audit_alloc_local"); > + goto out; > + } > + context->serial = audit_serial(); > + ktime_get_coarse_real_ts64(&context->ctime); > + context->local = true; > +out: > + return context; > +} > +EXPORT_SYMBOL(audit_alloc_local); > + > +void audit_free_context(struct audit_context *context) > +{ > + if (!context) > + return; > audit_free_module(context); > audit_free_names(context); > unroll_tree_refs(context, NULL, 0); > @@ -991,6 +1013,7 @@ static inline void audit_free_context(struct audit_context *context) > audit_proctitle_free(context); > kfree(context); > } > +EXPORT_SYMBOL(audit_free_context); > > static int audit_log_pid_context(struct audit_context *context, pid_t pid, > kuid_t auid, kuid_t uid, > @@ -2214,7 +2237,7 @@ EXPORT_SYMBOL_GPL(__audit_inode_child); > int auditsc_get_stamp(struct audit_context *ctx, > struct timespec64 *t, unsigned int *serial) > { > - if (!ctx->in_syscall) > + if (!ctx->in_syscall && !ctx->local) > return 0; > if (!ctx->serial) > ctx->serial = audit_serial(); > -- > 2.25.4 > - RGB -- Richard Guy Briggs <rgb(a)redhat.com&gt; Sr. S/W Engineer, Kernel Security, Base Operating Systems Remote, Ottawa, Red Hat Canada IRC: rgb, SunRaycer Voice: +1.647.777.2635, Internal: (81) 32635