d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Invoke the kld_* event handlers from linker_load_file() and

Browse Source 
linker_unload_file() rather than kern_kldload() and kern_kldunload(). This
ensures that the handlers are invoked for files that are loaded/unloaded
automatically as dependencies. Previously, they were only invoked for files
loaded by a user.

As a side effect, the kld_load and kld_unload handlers are now invoked with
the kernel linker lock exclusively held.

Reported by:	avg
Reviewed by:	jhb
MFC after:	2 weeks
This commit is contained in:
Mark Johnston 2013-12-19 03:48:36 +00:00
parent 8cf9cdeb65
commit 8f7254629f
1 changed files with 14 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
sys/kern/kern_linker.c
View File

@ -434,6 +434,7 @@ linker_load_file(const char *filename, linker_file_t *result)
linker_file_unload(lf, LINKER_UNLOAD_FORCE);
return (ENOEXEC);
}
EVENTHANDLER_INVOKE(kld_load, lf);
*result = lf;
return (0);
}
@ -609,6 +610,12 @@ linker_file_unload(linker_file_t file, int flags)
return (0);
}
/* Give eventhandlers a chance to prevent the unload. */
error = 0;
EVENTHANDLER_INVOKE(kld_unload_try, file, &error);
if (error != 0)
return (EBUSY);
KLD_DPF(FILE, ("linker_file_unload: file is unloading,"
" informing modules\n"));
@ -690,6 +697,10 @@ linker_file_unload(linker_file_t file, int flags)
}
LINKER_UNLOAD(file);
EVENTHANDLER_INVOKE(kld_unload, file->filename, file->address,
file->size);
if (file->filename) {
free(file->filename, M_LINKER);
file->filename = NULL;
@ -1033,10 +1044,7 @@ kern_kldload(struct thread *td, const char *file, int *fileid)
lf->userrefs++;
if (fileid != NULL)
*fileid = lf->id;
sx_downgrade(&kld_sx);
EVENTHANDLER_INVOKE(kld_load, lf);
sx_sunlock(&kld_sx);
sx_xunlock(&kld_sx);
done:
CURVNET_RESTORE();
@ -1066,9 +1074,6 @@ int
kern_kldunload(struct thread *td, int fileid, int flags)
{
linker_file_t lf;
char *filename = NULL;
caddr_t address;
size_t size;
int error = 0;
if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
@ -1083,10 +1088,7 @@ kern_kldunload(struct thread *td, int fileid, int flags)
if (lf) {
KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
EVENTHANDLER_INVOKE(kld_unload_try, lf, &error);
if (error != 0)
error = EBUSY;
else if (lf->userrefs == 0) {
if (lf->userrefs == 0) {
/*
* XXX: maybe LINKER_UNLOAD_FORCE should override ?
*/
@ -1094,11 +1096,6 @@ kern_kldunload(struct thread *td, int fileid, int flags)
" loaded by the kernel\n");
error = EBUSY;
} else {
/* Save data needed for the kld_unload callbacks. */
filename = strdup(lf->filename, M_TEMP);
address = lf->address;
size = lf->size;
lf->userrefs--;
error = linker_file_unload(lf, flags);
if (error)
@ -1106,14 +1103,7 @@ kern_kldunload(struct thread *td, int fileid, int flags)
}
} else
error = ENOENT;
if (error == 0) {
sx_downgrade(&kld_sx);
EVENTHANDLER_INVOKE(kld_unload, filename, address, size);
sx_sunlock(&kld_sx);
} else
sx_xunlock(&kld_sx);
free(filename, M_TEMP);
sx_xunlock(&kld_sx);
CURVNET_RESTORE();
return (error);