Add the ability to clean up all shared memory segments which are

unused in one go.

From the original PR:

	I've observed that linux apps running under the linuxulator
	have a habit of leaving behind shared memory segments which
	are unused, but which eventually cause the system to run
	out of free segments and these apps will stop working.
	ipcrm(1) currently only allows removal of unused message
	queues, shared memory segments and semaphores on an individual
	basis, or those having a matching (non-zero) key. However
	it would often be convenient to just do a complete cleanup
	of everything, usually as root.

PR:		bin/118292
Submitted by:	Callum Gibson <callumgibson@optusnet.com.au>
Not reviewed by:	grog@
Approved by:	grog@

3 files changed, 172 insertions, 17 deletions

diff --git a/usr.bin/ipcrm/Makefile b/usr.bin/ipcrm/Makefile
index 9c0e45c..47e4ccc 100644
--- a/usr.bin/ipcrm/Makefile
+++ b/usr.bin/ipcrm/Makefile
@@ -1,5 +1,10 @@
 # $FreeBSD$
 
 PROG=	ipcrm
+SRCS=	ipcrm.c ipc.c
+DPADD=	${LIBKVM}
+LDADD=	-lkvm
+CFLAGS+=-I${.CURDIR}/../ipcs
+.PATH:  ${.CURDIR}/../ipcs
 
 .include <bsd.prog.mk>
diff --git a/usr.bin/ipcrm/ipcrm.1 b/usr.bin/ipcrm/ipcrm.1
index 9e2a470..30378f2 100644
--- a/usr.bin/ipcrm/ipcrm.1
+++ b/usr.bin/ipcrm/ipcrm.1
@@ -23,7 +23,7 @@
 .\"
 .\" $FreeBSD$
 .\""
-.Dd August 8, 1994
+.Dd December 12, 2007
 .Dt IPCRM 1
 .Os
 .Sh NAME
@@ -31,6 +31,8 @@
 .Nd "remove the specified message queues, semaphore sets, and shared segments"
 .Sh SYNOPSIS
 .Nm
+.Op Fl W
+.Op Fl v
 .Op Fl q Ar msqid
 .Op Fl m Ar shmid
 .Op Fl s Ar semid
@@ -46,6 +48,31 @@ segments.
 These System V IPC objects can be specified by their
 creation ID or any associated key.
 .Pp
+The following options are generic:
+.Bl -tag -width indent
+.It Fl v
+If specified once with -W or with -1 for an object, it will show
+all removed objects.
+If specified twice with -W or with -1 for an objects, it will show
+all removed objects and all failed removals.
+.It Fl W
+Try to wipe all specified message queues, semaphores and shared
+memory segments.
+.It Fl y
+Use the
+.Xr kvm 3
+interface instead of the
+.Xr sysctl 3
+interface to extract the required information.
+If
+.Nm
+is to operate on the running system,
+using
+.Xr kvm 3
+will require read privileges to
+.Pa /dev/kmem .
+.El
+.Pp
 The following options are used to specify which IPC objects will be removed.
 Any number and combination of these options can be used:
 .Bl -tag -width indent
@@ -80,5 +107,13 @@ from the system.
 The identifiers and keys associated with these System V IPC objects can be
 determined by using
 .Xr ipcs 1 .
+If the identifier or the key is -1, it will remove all these objects.
 .Sh SEE ALSO
 .Xr ipcs 1
+.Sh HISTORY
+The wiping of all System V IPC objects was first implemented in
+.Fx 6.4 and 7.1.
+.Sh AUTHORS
+The original author was Adam Glass. 
+The wiping of all System V IPC objects was thought up by Callum
+Gibson and extended and implemented by Edwin Groothuis.
diff --git a/usr.bin/ipcrm/ipcrm.c b/usr.bin/ipcrm/ipcrm.c
index 1ced896..32887e0 100644
--- a/usr.bin/ipcrm/ipcrm.c
+++ b/usr.bin/ipcrm/ipcrm.c
@@ -27,42 +27,47 @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
-#include <sys/types.h>
-#include <sys/ipc.h>
-#include <sys/msg.h>
+#include <sys/param.h>
+#define _KERNEL
 #include <sys/sem.h>
 #include <sys/shm.h>
+#include <sys/msg.h>
+#undef _KERNEL
 
 #include <ctype.h>
 #include <err.h>
-#include <signal.h>
+#include <grp.h>
+#include <kvm.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 
-#define IPC_TO_STR(x) (x == 'Q' ? "msq" : (x == 'M' ? "shm" : "sem"))
-#define IPC_TO_STRING(x) (x == 'Q' ? "message queue" : \
-	(x == 'M' ? "shared memory segment" : "semaphore"))
+#include "ipc.h"
+
+int	signaled;
+int	errflg;
+int	rmverbose = 0;
 
-int signaled;
+void	usage(void);
 
-void usage(void);
-int msgrm(key_t, int);
-int shmrm(key_t, int);
-int semrm(key_t, int);
-void not_configured(int);
+int	msgrm(key_t, int);
+int	shmrm(key_t, int);
+int	semrm(key_t, int);
+void	not_configured(int);
 
 void
 usage(void)
 {
 
 	fprintf(stderr,
-	    "usage: ipcrm [-q msqid] [-m shmid] [-s semid]\n"
+	    "usage: ipcrm [-W] [-v[v]]\n"
+	    "             [-q msqid] [-m shmid] [-s semid]\n"
 	    "             [-Q msgkey] [-M shmkey] [-S semkey] ...\n");
 	exit(1);
 }
@@ -71,11 +76,40 @@ int
 msgrm(key_t key, int id)
 {
 
+	if (key == -1 || id == -1) {
+		struct msqid_kernel *kxmsqids;
+		size_t kxmsqids_len;
+		int num;
+
+		kget(X_MSGINFO, &msginfo, sizeof(msginfo));
+		kxmsqids_len = sizeof(struct msqid_kernel) * msginfo.msgmni;
+		kxmsqids = malloc(kxmsqids_len);
+		kget(X_MSQIDS, kxmsqids, kxmsqids_len);
+		num = msginfo.msgmni;
+		while (num-- && !signaled)
+			if (kxmsqids[num].u.msg_qbytes != 0) {
+				id = IXSEQ_TO_IPCID(num,
+					kxmsqids[num].u.msg_perm);
+				if (msgctl(id, IPC_RMID, NULL) < 0) {
+					if (rmverbose > 1)
+						warn("msqid(%d): ", id);
+					errflg++;
+				} else
+					if (rmverbose)
+						printf(
+						    "Removed %s %d\n",
+						    IPC_TO_STRING('Q'),
+						    id);
+			}
+		return signaled ? -1 : 0;       /* errors maybe handled above */
+	}
+
 	if (key) {
 		id = msgget(key, 0);
 		if (id == -1)
 			return -1;
 	}
+
 	return msgctl(id, IPC_RMID, NULL);
 }
 
@@ -83,11 +117,40 @@ int
 shmrm(key_t key, int id)
 {
 
+	if (key == -1 || id == -1) {
+		struct shmid_kernel *kxshmids;
+		size_t kxshmids_len;
+		int num;
+
+		kget(X_SHMINFO, &shminfo, sizeof(shminfo));
+		kxshmids_len = sizeof(struct shmid_kernel) * shminfo.shmmni;
+		kxshmids = malloc(kxshmids_len);
+		kget(X_SHMSEGS, kxshmids, kxshmids_len);
+		num = shminfo.shmmni;
+		while (num-- && !signaled)
+			if (kxshmids[num].u.shm_perm.mode & 0x0800) {
+				id = IXSEQ_TO_IPCID(num,
+					kxshmids[num].u.shm_perm);
+				if (shmctl(id, IPC_RMID, NULL) < 0) {
+					if (rmverbose > 1)
+						warn("shmid(%d): ", id);
+					errflg++;
+				} else
+					if (rmverbose)
+						printf(
+						    "Removed %s %d\n",
+						    IPC_TO_STRING('M'),
+						    id);
+			}
+		return signaled ? -1 : 0;       /* errors maybe handled above */
+	}
+
 	if (key) {
 		id = shmget(key, 0, 0);
 		if (id == -1)
 			return -1;
 	}
+
 	return shmctl(id, IPC_RMID, NULL);
 }
 
@@ -96,11 +159,40 @@ semrm(key_t key, int id)
 {
 	union semun arg;
 
+	if (key == -1 || id == -1) {
+		struct semid_kernel *kxsema;
+		size_t kxsema_len;
+		int num;
+
+		kget(X_SEMINFO, &seminfo, sizeof(seminfo));
+		kxsema_len = sizeof(struct semid_kernel) * seminfo.semmni;
+		kxsema = malloc(kxsema_len);
+		kget(X_SEMA, kxsema, kxsema_len);
+		num = seminfo.semmni;
+		while (num-- && !signaled)
+			if ((kxsema[num].u.sem_perm.mode & SEM_ALLOC) != 0) {
+				id = IXSEQ_TO_IPCID(num,
+					kxsema[num].u.sem_perm);
+				if (semctl(id, IPC_RMID, NULL) < 0) {
+					if (rmverbose > 1)
+						warn("semid(%d): ", id);
+					errflg++;
+				} else
+					if (rmverbose)
+						printf(
+						    "Removed %s %d\n",
+						    IPC_TO_STRING('S'),
+						    id);
+			}
+		return signaled ? -1 : 0;       /* errors maybe handled above */
+	}
+
 	if (key) {
 		id = semget(key, 0, 0);
 		if (id == -1)
 			return -1;
 	}
+
 	return semctl(id, 0, IPC_RMID, arg);
 }
 
@@ -114,12 +206,26 @@ not_configured(int signo __unused)
 int
 main(int argc, char *argv[])
 {
-	int c, result, errflg, target_id;
+	int c, result, target_id;
 	key_t target_key;
 
+	while ((c = getopt(argc, argv, "q:m:s:Q:M:S:vWy")) != -1) {
+
+		signaled = 0;
+		switch (c) {
+		case 'v':
+			rmverbose++;
+			break;
+		case 'y':
+			use_sysctl = 0;
+			break;
+		}
+	}
+
+	optind = 1;
 	errflg = 0;
 	signal(SIGSYS, not_configured);
-	while ((c = getopt(argc, argv, ":q:m:s:Q:M:S:")) != -1) {
+	while ((c = getopt(argc, argv, "q:m:s:Q:M:S:vWy")) != -1) {
 
 		signaled = 0;
 		switch (c) {
@@ -171,6 +277,15 @@ main(int argc, char *argv[])
 					    IPC_TO_STRING(c));
 			}
 			break;
+		case 'v':
+		case 'y':
+			/* Handled in other getopt() loop */
+			break;
+		case 'W':
+			msgrm(-1, 0);
+			shmrm(-1, 0);
+			semrm(-1, 0);
+			break;
 		case ':':
 			fprintf(stderr,
 			    "option -%c requires an argument\n", optopt);