elf: Add _dl_audit_activity_map and _dl_audit_activity_nsid

It consolidates the code required to call la_activity audit
callback.

Also for a new Lmid_t the namespace link_map list are empty, so it
requires to check if before using it.  This can happen for when audit
module is used along with dlmopen.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
This commit is contained in:
Adhemerval Zanella 2021-07-20 11:03:34 -03:00
parent aee6e90f93
commit 3dac3959a5
6 changed files with 45 additions and 111 deletions

View File

@ -18,6 +18,32 @@
#include <ldsodefs.h>
void
_dl_audit_activity_map (struct link_map *l, int action)
{
struct audit_ifaces *afct = GLRO(dl_audit);
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
afct->activity (&link_map_audit_state (l, cnt)->cookie, action);
afct = afct->next;
}
}
void
_dl_audit_activity_nsid (Lmid_t nsid, int action)
{
/* If head is NULL, the namespace has become empty, and the audit interface
does not give us a way to signal LA_ACT_CONSISTENT for it because the
first loaded module is used to identify the namespace. */
struct link_map *head = GL(dl_ns)[nsid]._ns_loaded;
if (__glibc_likely (GLRO(dl_naudit) == 0)
|| head == NULL || head->l_auditing)
return;
_dl_audit_activity_map (head, action);
}
void
_dl_audit_objopen (struct link_map *l, Lmid_t nsid)
{

View File

@ -472,25 +472,7 @@ _dl_close_worker (struct link_map *map, bool force)
#ifdef SHARED
/* Auditing checkpoint: we will start deleting objects. */
if (__glibc_unlikely (do_audit))
{
struct link_map *head = ns->_ns_loaded;
struct audit_ifaces *afct = GLRO(dl_audit);
/* Do not call the functions for any auditing object. */
if (head->l_auditing == 0)
{
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
{
struct auditstate *state = link_map_audit_state (head, cnt);
afct->activity (&state->cookie, LA_ACT_DELETE);
}
afct = afct->next;
}
}
}
_dl_audit_activity_nsid (nsid, LA_ACT_DELETE);
#endif
/* Notify the debugger we are about to remove some loaded objects. */
@ -785,32 +767,9 @@ _dl_close_worker (struct link_map *map, bool force)
__rtld_lock_unlock_recursive (GL(dl_load_tls_lock));
#ifdef SHARED
/* Auditing checkpoint: we have deleted all objects. */
if (__glibc_unlikely (do_audit))
{
struct link_map *head = ns->_ns_loaded;
/* If head is NULL, the namespace has become empty, and the
audit interface does not give us a way to signal
LA_ACT_CONSISTENT for it because the first loaded module is
used to identify the namespace.
Furthermore, do not notify auditors of the cleanup of a
failed audit module loading attempt. */
if (head != NULL && head->l_auditing == 0)
{
struct audit_ifaces *afct = GLRO(dl_audit);
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
{
struct auditstate *state = link_map_audit_state (head, cnt);
afct->activity (&state->cookie, LA_ACT_CONSISTENT);
}
afct = afct->next;
}
}
}
/* Auditing checkpoint: we have deleted all objects. Also, do not notify
auditors of the cleanup of a failed audit module loading attempt. */
_dl_audit_activity_nsid (nsid, LA_ACT_CONSISTENT);
#endif
if (__builtin_expect (ns->_ns_loaded == NULL, 0)

View File

@ -1483,24 +1483,8 @@ cannot enable executable stack as shared object requires");
/* Auditing checkpoint: we are going to add new objects. Since this
is called after _dl_add_to_namespace_list the namespace is guaranteed
to not be empty. */
if ((mode & __RTLD_AUDIT) == 0
&& __glibc_unlikely (GLRO(dl_naudit) > 0))
{
struct link_map *head = GL(dl_ns)[nsid]._ns_loaded;
/* Do not call the functions for any auditing object. */
if (head->l_auditing == 0)
{
struct audit_ifaces *afct = GLRO(dl_audit);
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
afct->activity (&link_map_audit_state (head, cnt)->cookie,
LA_ACT_ADD);
afct = afct->next;
}
}
}
if ((mode & __RTLD_AUDIT) == 0)
_dl_audit_activity_nsid (nsid, LA_ACT_ADD);
#endif
/* Notify the debugger we have added some objects. We need to

View File

@ -611,25 +611,7 @@ dl_open_worker_begin (void *a)
#ifdef SHARED
/* Auditing checkpoint: we have added all objects. */
if (__glibc_unlikely (GLRO(dl_naudit) > 0))
{
struct link_map *head = GL(dl_ns)[new->l_ns]._ns_loaded;
/* Do not call the functions for any auditing object. */
if (head->l_auditing == 0)
{
struct audit_ifaces *afct = GLRO(dl_audit);
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
{
struct auditstate *state = link_map_audit_state (head, cnt);
afct->activity (&state->cookie, LA_ACT_CONSISTENT);
}
afct = afct->next;
}
}
}
_dl_audit_activity_nsid (new->l_ns, LA_ACT_CONSISTENT);
#endif
/* Notify the debugger all new objects are now ready to go. */

View File

@ -1794,18 +1794,7 @@ dl_main (const ElfW(Phdr) *phdr,
/* Auditing checkpoint: we are ready to signal that the initial map
is being constructed. */
if (__glibc_unlikely (GLRO(dl_naudit) > 0))
{
struct audit_ifaces *afct = GLRO(dl_audit);
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
afct->activity (&link_map_audit_state (main_map, cnt)->cookie,
LA_ACT_ADD);
afct = afct->next;
}
}
_dl_audit_activity_map (main_map, LA_ACT_ADD);
/* We have two ways to specify objects to preload: via environment
variable and via the file /etc/ld.so.preload. The latter can also
@ -2486,23 +2475,7 @@ dl_main (const ElfW(Phdr) *phdr,
#ifdef SHARED
/* Auditing checkpoint: we have added all objects. */
if (__glibc_unlikely (GLRO(dl_naudit) > 0))
{
struct link_map *head = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
/* Do not call the functions for any auditing object. */
if (head->l_auditing == 0)
{
struct audit_ifaces *afct = GLRO(dl_audit);
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->activity != NULL)
afct->activity (&link_map_audit_state (head, cnt)->cookie,
LA_ACT_CONSISTENT);
afct = afct->next;
}
}
}
_dl_audit_activity_nsid (LM_ID_BASE, LA_ACT_CONSISTENT);
#endif
/* Notify the debugger all new objects are now ready to go. We must re-get

View File

@ -1396,6 +1396,16 @@ link_map_audit_state (struct link_map *l, size_t index)
}
}
/* Call the la_activity from the audit modules from the link map L and issues
the ACTION argument. */
void _dl_audit_activity_map (struct link_map *l, int action)
attribute_hidden;
/* Call the la_activity from the audit modules from the link map from the
namespace NSID and issues the ACTION argument. */
void _dl_audit_activity_nsid (Lmid_t nsid, int action)
attribute_hidden;
/* Call the la_objopen from the audit modules for the link_map L on the
namespace identification NSID. */
void _dl_audit_objopen (struct link_map *l, Lmid_t nsid)