989d921f5d
I'm very pleased to announce the release of our new website and documentation using the new toolchain with Hugo and AsciiDoctor. To get more information about the new toolchain please read the FreeBSD Documentation Project Primer[1], Hugo docs[2] and AsciiDoctor docs[3]. Acknowledgment: Benedict Reuschling <bcr@> Glen Barber <gjb@> Hiroki Sato <hrs@> Li-Wen Hsu <lwhsu@> Sean Chittenden <seanc@> The FreeBSD Foundation [1] https://docs.FreeBSD.org/en/books/fdp-primer/ [2] https://gohugo.io/documentation/ [3] https://docs.asciidoctor.org/home/ Approved by: doceng, core
109 lines
3.6 KiB
Groff
109 lines
3.6 KiB
Groff
--- sys/kern/kern_descrip.c Fri Dec 14 13:26:24 2001
|
|
+++ sys/kern/kern_descrip.c Mon Apr 22 16:38:20 2002
|
|
@@ -50,6 +50,7 @@
|
|
#include <sys/sysctl.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/proc.h>
|
|
+#include <sys/namei.h>
|
|
#include <sys/file.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/filio.h>
|
|
@@ -1183,6 +1184,63 @@
|
|
}
|
|
while (fdp->fd_lastfile > 0 && fdp->fd_ofiles[fdp->fd_lastfile] == NULL)
|
|
fdp->fd_lastfile--;
|
|
+}
|
|
+
|
|
+/*
|
|
+ * It is unsafe for set[ug]id processes to be started with file
|
|
+ * descriptors 0..2 closed, as these descriptors are given implicit
|
|
+ * significance in the Standard C library. fdcheckstd() will create a
|
|
+ * descriptor referencing /dev/null for each of stdin, stdout, and
|
|
+ * stderr that is not already open.
|
|
+ */
|
|
+int
|
|
+fdcheckstd(p)
|
|
+ struct proc *p;
|
|
+{
|
|
+ struct nameidata nd;
|
|
+ struct filedesc *fdp;
|
|
+ struct file *fp;
|
|
+ register_t retval;
|
|
+ int fd, i, error, flags, devnull;
|
|
+
|
|
+ fdp = p->p_fd;
|
|
+ if (fdp == NULL)
|
|
+ return (0);
|
|
+ devnull = -1;
|
|
+ error = 0;
|
|
+ for (i = 0; i < 3; i++) {
|
|
+ if (fdp->fd_ofiles[i] != NULL)
|
|
+ continue;
|
|
+ if (devnull < 0) {
|
|
+ error = falloc(p, &fp, &fd);
|
|
+ if (error != 0)
|
|
+ break;
|
|
+ NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/null",
|
|
+ p);
|
|
+ flags = FREAD | FWRITE;
|
|
+ error = vn_open(&nd, flags, 0);
|
|
+ if (error != 0) {
|
|
+ fdp->fd_ofiles[i] = NULL;
|
|
+ fdrop(fp, p);
|
|
+ break;
|
|
+ }
|
|
+ NDFREE(&nd, NDF_ONLY_PNBUF);
|
|
+ fp->f_data = (caddr_t)nd.ni_vp;
|
|
+ fp->f_flag = flags;
|
|
+ fp->f_ops = &vnops;
|
|
+ fp->f_type = DTYPE_VNODE;
|
|
+ VOP_UNLOCK(nd.ni_vp, 0, p);
|
|
+ devnull = fd;
|
|
+ } else {
|
|
+ error = fdalloc(p, 0, &fd);
|
|
+ if (error != 0)
|
|
+ break;
|
|
+ error = do_dup(fdp, devnull, fd, &retval, p);
|
|
+ if (error != 0)
|
|
+ break;
|
|
+ }
|
|
+ }
|
|
+ return (error);
|
|
}
|
|
|
|
/*
|
|
diff --exclude=CVS -ruN sys/kern/kern_exec.c sys/kern/kern_exec.c
|
|
--- sys/kern/kern_exec.c Tue Jan 22 11:22:59 2002
|
|
+++ sys/kern/kern_exec.c Mon Jul 29 22:21:49 2002
|
|
@@ -328,6 +328,12 @@
|
|
vrele(vtmp);
|
|
}
|
|
}
|
|
+ /* Close any file descriptors 0..2 that reference procfs */
|
|
+ setugidsafety(p);
|
|
+ /* Make sure file descriptors 0..2 are in use. */
|
|
+ error = fdcheckstd(p);
|
|
+ if (error != 0)
|
|
+ goto exec_fail_dealloc;
|
|
/*
|
|
* Set the new credentials.
|
|
*/
|
|
@@ -336,7 +342,6 @@
|
|
change_euid(p, attr.va_uid);
|
|
if (attr.va_mode & VSGID)
|
|
p->p_ucred->cr_gid = attr.va_gid;
|
|
- setugidsafety(p);
|
|
} else {
|
|
if (p->p_ucred->cr_uid == p->p_cred->p_ruid &&
|
|
p->p_ucred->cr_gid == p->p_cred->p_rgid)
|
|
diff --exclude=CVS -ruN sys/sys/filedesc.h sys/sys/filedesc.h
|
|
--- sys/sys/filedesc.h Sat Nov 25 20:30:08 2000
|
|
+++ sys/sys/filedesc.h Sun Apr 21 08:08:57 2002
|
|
@@ -142,6 +142,7 @@
|
|
void fdfree __P((struct proc *p));
|
|
int closef __P((struct file *fp,struct proc *p));
|
|
void fdcloseexec __P((struct proc *p));
|
|
+int fdcheckstd __P((struct proc *p));
|
|
struct file *holdfp __P((struct filedesc* fdp, int fd, int flag));
|
|
int getvnode __P((struct filedesc *fdp, int fd, struct file **fpp));
|
|
int fdissequential __P((struct file *));
|