Module Name: src
Committed By: riastradh
Date: Sun Jun 13 09:30:48 UTC 2021
Modified Files:
src/sys/kern: subr_autoconf.c
Log Message:
autoconf(9): Take kernel lock in config_detach.
config_detach is used in too many places to audit for now -- so
although I'm quite sure it is racy (e.g., with cloning devices and
drvctl: drvctl -d a newly opened fss0 before sc_state has
transitioned from FSS_IDLE), this will mitigate the immediate fallout
until we can properly fix autoconf's notions of device pointers.
To generate a diff of this commit:
cvs rdiff -u -r1.286 -r1.287 src/sys/kern/subr_autoconf.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/subr_autoconf.c
diff -u src/sys/kern/subr_autoconf.c:1.286 src/sys/kern/subr_autoconf.c:1.287
--- src/sys/kern/subr_autoconf.c:1.286 Sun Jun 13 00:11:46 2021
+++ src/sys/kern/subr_autoconf.c Sun Jun 13 09:30:48 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_autoconf.c,v 1.286 2021/06/13 00:11:46 riastradh Exp $ */
+/* $NetBSD: subr_autoconf.c,v 1.287 2021/06/13 09:30:48 riastradh Exp $ */
/*
* Copyright (c) 1996, 2000 Christopher G. Demetriou
@@ -79,7 +79,7 @@
#define __SUBR_AUTOCONF_PRIVATE /* see <sys/device.h> */
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.286 2021/06/13 00:11:46 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.287 2021/06/13 09:30:48 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_ddb.h"
@@ -1969,7 +1969,7 @@ config_detach(device_t dev, int flags)
device_t d __diagused;
int rv = 0;
- KASSERT(KERNEL_LOCKED_P());
+ KERNEL_LOCK(1, NULL);
cf = dev->dv_cfdata;
KASSERTMSG((cf == NULL || cf->cf_fstate == FSTATE_FOUND ||
@@ -1988,8 +1988,10 @@ config_detach(device_t dev, int flags)
* attached.
*/
rv = config_detach_enter(dev);
- if (rv)
+ if (rv) {
+ KERNEL_UNLOCK_ONE(NULL);
return rv;
+ }
mutex_enter(&alldevs_lock);
if (dev->dv_del_gen != 0) {
@@ -1999,6 +2001,7 @@ config_detach(device_t dev, int flags)
device_xname(dev));
#endif /* DIAGNOSTIC */
config_detach_exit(dev);
+ KERNEL_UNLOCK_ONE(NULL);
return ENOENT;
}
alldevs_nwrite++;
@@ -2095,6 +2098,8 @@ out:
}
config_alldevs_exit(&af);
+ KERNEL_UNLOCK_ONE(NULL);
+
return rv;
}
