Module Name: src
Committed By: kamil
Date: Fri May 31 23:01:39 UTC 2019
Modified Files:
src/sys/kern: kern_proc.c
src/sys/sys: sysctl.h
Log Message:
Implement KERN_PROC_CWD in sysctl(3)
Retrieve specified process current working directory.
Fixes PR kern/50620 by Thomas Klausner.
To generate a diff of this commit:
cvs rdiff -u -r1.228 -r1.229 src/sys/kern/kern_proc.c
cvs rdiff -u -r1.229 -r1.230 src/sys/sys/sysctl.h
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/kern_proc.c
diff -u src/sys/kern/kern_proc.c:1.228 src/sys/kern/kern_proc.c:1.229
--- src/sys/kern/kern_proc.c:1.228 Fri Mar 1 11:06:57 2019
+++ src/sys/kern/kern_proc.c Fri May 31 23:01:39 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_proc.c,v 1.228 2019/03/01 11:06:57 pgoyette Exp $ */
+/* $NetBSD: kern_proc.c,v 1.229 2019/05/31 23:01:39 kamil Exp $ */
/*-
* Copyright (c) 1999, 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.228 2019/03/01 11:06:57 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_proc.c,v 1.229 2019/05/31 23:01:39 kamil Exp $");
#ifdef _KERNEL_OPT
#include "opt_kstack.h"
@@ -246,6 +246,7 @@ static kauth_listener_t proc_listener;
static void fill_proc(const struct proc *, struct proc *, bool);
static int fill_pathname(struct lwp *, pid_t, void *, size_t *);
+static int fill_cwd(struct lwp *, pid_t, void *, size_t *);
static int
proc_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
@@ -1945,6 +1946,12 @@ sysctl_kern_proc_args(SYSCTLFN_ARGS)
sysctl_relock();
return error;
+ case KERN_PROC_CWD:
+ sysctl_unlock();
+ error = fill_cwd(l, pid, oldp, oldlenp);
+ sysctl_relock();
+ return error;
+
case KERN_PROC_ARGV:
case KERN_PROC_NARGV:
case KERN_PROC_ENV:
@@ -2577,6 +2584,58 @@ fill_pathname(struct lwp *l, pid_t pid,
return error;
}
+static int
+fill_cwd(struct lwp *l, pid_t pid, void *oldp, size_t *oldlenp)
+{
+ int error;
+ struct proc *p;
+ char *path;
+ char *bp, *bend;
+ struct cwdinfo *cwdi;
+ struct vnode *vp;
+ size_t len, lenused;
+ const int flags = GETCWD_CHECK_ACCESS;
+
+ if ((error = proc_find_locked(l, &p, pid)) != 0)
+ return error;
+
+ len = MAXPATHLEN * 4;
+ if (*oldlenp < 2) {
+ if (pid != -1)
+ mutex_exit(p->p_lock);
+ return ERANGE;
+ }
+
+ path = kmem_alloc(len, KM_SLEEP);
+
+ bp = &path[len];
+ bend = bp;
+ *(--bp) = '\0';
+
+ cwdi = p->p_cwdi;
+ rw_enter(&cwdi->cwdi_lock, RW_READER);
+ vp = cwdi->cwdi_cdir;
+ error = getcwd_common(vp, NULL, &bp, path, len/2, flags, l);
+ rw_exit(&cwdi->cwdi_lock);
+
+ if (error)
+ goto out;
+
+ lenused = bend - bp;
+
+ if (oldp != NULL) {
+ error = sysctl_copyout(l, bp, oldp, lenused);
+ if (error == 0 && *oldlenp < lenused)
+ error = ENOSPC;
+ }
+ *oldlenp = lenused;
+out:
+ if (pid != -1)
+ mutex_exit(p->p_lock);
+ kmem_free(path, len);
+ return error;
+}
+
int
proc_getauxv(struct proc *p, void **buf, size_t *len)
{
Index: src/sys/sys/sysctl.h
diff -u src/sys/sys/sysctl.h:1.229 src/sys/sys/sysctl.h:1.230
--- src/sys/sys/sysctl.h:1.229 Wed Dec 5 18:16:51 2018
+++ src/sys/sys/sysctl.h Fri May 31 23:01:39 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: sysctl.h,v 1.229 2018/12/05 18:16:51 christos Exp $ */
+/* $NetBSD: sysctl.h,v 1.230 2019/05/31 23:01:39 kamil Exp $ */
/*
* Copyright (c) 1989, 1993
@@ -585,6 +585,7 @@ struct kinfo_lwp {
#define KERN_PROC_ENV 3 /* environ */
#define KERN_PROC_NENV 4 /* number of strings in above */
#define KERN_PROC_PATHNAME 5 /* path to executable */
+#define KERN_PROC_CWD 6 /* current working dir */
/*
* KERN_SYSVIPC subtypes
