Re: [RFC] [PATCH] audit: log module name on init_module

On Thu, Jan 26, 2017 at 4:21 PM, Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > This adds a new auxiliary record MODULE_INIT to the SYSCALL event. > > We get finit_module for free since it made most sense to hook this in to > load_module(). > > https://github.com/linux-audit/audit-kernel/issues/7 > https://github.com/linux-audit/audit-kernel/wiki/RFE-Module-load-record-f... Consistency nit: capitalize the first letter in the wiki page words (see the existing RFE pages) > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > --- > include/linux/audit.h | 12 ++++++++++++ > include/uapi/linux/audit.h | 1 + > kernel/audit.h | 3 +++ > kernel/auditsc.c | 20 ++++++++++++++++++++ > kernel/module.c | 5 ++++- > 5 files changed, 40 insertions(+), 1 deletions(-) > > diff --git a/include/linux/audit.h b/include/linux/audit.h > index 2be99b2..7bb23d5 100644 > --- a/include/linux/audit.h > +++ b/include/linux/audit.h > @@ -360,6 +360,7 @@ extern int __audit_log_bprm_fcaps(struct linux_binprm *bprm, > const struct cred *old); > extern void __audit_log_capset(const struct cred *new, const struct cred *old); > extern void __audit_mmap_fd(int fd, int flags); > +extern void __audit_module_init(char *name); > > static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp) > { > @@ -450,6 +451,12 @@ static inline void audit_mmap_fd(int fd, int flags) > __audit_mmap_fd(fd, flags); > } > > +static inline void audit_module_init(char *name) > +{ > + if (!audit_dummy_context()) > + __audit_module_init(name); > +} More on this below, but I was expecting the function above to named audit_log_kern_module(), or something similar.

> extern int audit_n_rules; > extern int audit_signals; > #else /* CONFIG_AUDITSYSCALL */ > @@ -561,6 +568,11 @@ static inline void audit_log_capset(const struct cred *new, > { } > static inline void audit_mmap_fd(int fd, int flags) > { } > + > +static inline void audit_module_init(char *name) > +{ > +} > + > static inline void audit_ptrace(struct task_struct *t) > { } > #define audit_n_rules 0 > diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h > index 3f24110..4a328b4 100644 > --- a/include/uapi/linux/audit.h > +++ b/include/uapi/linux/audit.h > @@ -111,6 +111,7 @@ > #define AUDIT_PROCTITLE 1327 /* Proctitle emit event */ > #define AUDIT_FEATURE_CHANGE 1328 /* audit log listing feature changes */ > #define AUDIT_REPLACE 1329 /* Replace auditd if this packet unanswerd */ > +#define AUDIT_MODULE_INIT 1330 /* Module init event */ > > #define AUDIT_AVC 1400 /* SE Linux avc denial or grant */ > #define AUDIT_SELINUX_ERR 1401 /* Internal SE Linux Errors */ > diff --git a/kernel/audit.h b/kernel/audit.h > index 431444c..144b7eb 100644 > --- a/kernel/audit.h > +++ b/kernel/audit.h > @@ -199,6 +199,9 @@ struct audit_context { > struct { > int argc; > } execve; > + struct { > + char *name; > + } module; > }; > int fds[2]; > struct audit_proctitle proctitle; > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index bb5f504..3e12678 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -1172,6 +1172,14 @@ out: > kfree(buf_head); > } > > +static void audit_log_kern_module(struct audit_context *context, > + struct audit_buffer **ab) > +{ > + audit_log_format(*ab, " name="); > + audit_log_untrustedstring(*ab, context->module.name); > + kfree(context->module.name); > +} > + > static void show_special(struct audit_context *context, int *call_panic) > { > struct audit_buffer *ab; > @@ -1268,6 +1276,9 @@ static void show_special(struct audit_context *context, int *call_panic) > case AUDIT_EXECVE: { > audit_log_execve_info(context, &ab); > break; } > + case AUDIT_MODULE_INIT: > + audit_log_kern_module(context, &ab); > + break; With the exception of AUDIT_EXECVE everything else in show_special() is simply open coded inside the show_special() function; considering that audit_log_kern_module() is trivial it seems like a separate function isn't really needed here. > } > audit_log_end(ab); > } > @@ -2368,6 +2379,15 @@ void __audit_mmap_fd(int fd, int flags) > context->type = AUDIT_MMAP; > } > > +void __audit_module_init(char *name) > +{ > + struct audit_context *context = current->audit_context; > + > + context->module.name = kmalloc(strlen(name) + 1, GFP_KERNEL); > + strcpy(context->module.name, name); > + context->type = AUDIT_MODULE_INIT; > +} > + > static void audit_log_task(struct audit_buffer *ab) > { > kuid_t auid, uid; > diff --git a/kernel/module.c b/kernel/module.c > index 529efae..678407e 100644 > --- a/kernel/module.c > +++ b/kernel/module.c > @@ -61,6 +61,7 @@ > #include <linux/pfn.h> > #include <linux/bsearch.h> > #include <linux/dynamic_debug.h> > +#include <linux/audit.h> > #include <uapi/linux/module.h> > #include "module-internal.h" > > @@ -3593,6 +3594,8 @@ static int load_module(struct load_info *info, const char __user *uargs, > goto free_copy; > } > > + audit_module_init(mod->name); > + > /* Reserve our place in the list. */ > err = add_unformed_module(mod); > if (err) > @@ -3681,7 +3684,7 @@ static int load_module(struct load_info *info, const char __user *uargs, > mod->name, after_dashes); > } > > - /* Link in to syfs. */ > + /* Link in to sysfs. */ > err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp); > if (err < 0) > goto coming_cleanup; paul moore