Module Name: src
Committed By: christos
Date: Mon May 2 01:46:31 UTC 2016
Modified Files:
src/bin/sh: cd.c eval.c input.c jobs.c parser.c redir.c redir.h
Log Message:
Fix handing of user file descriptors outside the 0..9 range.
Also, move (most of) the shell's internal use fd's to much
higher values (depending upon what ulimit -n allows) so they
are less likely to clash with user supplied fd numbers. A future
patch will (hopefully) avoid this problem completely by dynamically
moving the shell's internal fds around as needed. (From kre@)
To generate a diff of this commit:
cvs rdiff -u -r1.45 -r1.46 src/bin/sh/cd.c
cvs rdiff -u -r1.119 -r1.120 src/bin/sh/eval.c
cvs rdiff -u -r1.48 -r1.49 src/bin/sh/input.c
cvs rdiff -u -r1.75 -r1.76 src/bin/sh/jobs.c
cvs rdiff -u -r1.116 -r1.117 src/bin/sh/parser.c
cvs rdiff -u -r1.42 -r1.43 src/bin/sh/redir.c
cvs rdiff -u -r1.18 -r1.19 src/bin/sh/redir.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/bin/sh/cd.c
diff -u src/bin/sh/cd.c:1.45 src/bin/sh/cd.c:1.46
--- src/bin/sh/cd.c:1.45 Sun Jan 3 22:00:24 2016
+++ src/bin/sh/cd.c Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: cd.c,v 1.45 2016/01/04 03:00:24 christos Exp $ */
+/* $NetBSD: cd.c,v 1.46 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)cd.c 8.2 (Berkeley) 5/4/95";
#else
-__RCSID("$NetBSD: cd.c,v 1.45 2016/01/04 03:00:24 christos Exp $");
+__RCSID("$NetBSD: cd.c,v 1.46 2016/05/02 01:46:31 christos Exp $");
#endif
#endif /* not lint */
@@ -427,11 +427,7 @@ find_curdir(int noerror)
jp = makejob(NULL, 1);
if (forkshell(jp, NULL, FORK_NOJOB) == 0) {
(void) close(pip[0]);
- if (pip[1] != 1) {
- close(1);
- copyfd(pip[1], 1, 1, 0);
- close(pip[1]);
- }
+ movefd(pip[1], 1);
(void) execl("/bin/pwd", "pwd", (char *)0);
error("Cannot exec /bin/pwd");
}
Index: src/bin/sh/eval.c
diff -u src/bin/sh/eval.c:1.119 src/bin/sh/eval.c:1.120
--- src/bin/sh/eval.c:1.119 Wed Mar 16 17:20:59 2016
+++ src/bin/sh/eval.c Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: eval.c,v 1.119 2016/03/16 21:20:59 christos Exp $ */
+/* $NetBSD: eval.c,v 1.120 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)eval.c 8.9 (Berkeley) 6/8/95";
#else
-__RCSID("$NetBSD: eval.c,v 1.119 2016/03/16 21:20:59 christos Exp $");
+__RCSID("$NetBSD: eval.c,v 1.120 2016/05/02 01:46:31 christos Exp $");
#endif
#endif /* not lint */
@@ -508,6 +508,7 @@ expredir(union node *n)
for (redir = n ; redir ; redir = redir->nfile.next) {
struct arglist fn;
+
fn.lastp = &fn.list;
switch (redir->type) {
case NFROMTO:
@@ -566,18 +567,11 @@ evalpipe(union node *n)
}
if (forkshell(jp, lp->n, n->npipe.backgnd ? FORK_BG : FORK_FG) == 0) {
INTON;
- if (prevfd > 0) {
- close(0);
- copyfd(prevfd, 0, 1, 0);
- close(prevfd);
- }
+ if (prevfd > 0)
+ movefd(prevfd, 0);
if (pip[1] >= 0) {
close(pip[0]);
- if (pip[1] != 1) {
- close(1);
- copyfd(pip[1], 1, 1, 0);
- close(pip[1]);
- }
+ movefd(pip[1], 1);
}
evaltree(lp->n, EV_EXIT);
}
@@ -638,11 +632,7 @@ evalbackcmd(union node *n, struct backcm
if (forkshell(jp, n, FORK_NOJOB) == 0) {
FORCEINTON;
close(pip[0]);
- if (pip[1] != 1) {
- close(1);
- copyfd(pip[1], 1, 1, 0);
- close(pip[1]);
- }
+ movefd(pip[1], 1);
eflag = 0;
evaltree(n, EV_EXIT);
/* NOTREACHED */
@@ -970,11 +960,7 @@ normal_fork:
FORCEINTON;
}
close(pip[0]);
- if (pip[1] != 1) {
- close(1);
- copyfd(pip[1], 1, 1, 0);
- close(pip[1]);
- }
+ movefd(pip[1], 1);
}
flags |= EV_EXIT;
}
Index: src/bin/sh/input.c
diff -u src/bin/sh/input.c:1.48 src/bin/sh/input.c:1.49
--- src/bin/sh/input.c:1.48 Sun Mar 27 10:34:46 2016
+++ src/bin/sh/input.c Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: input.c,v 1.48 2016/03/27 14:34:46 christos Exp $ */
+/* $NetBSD: input.c,v 1.49 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)input.c 8.3 (Berkeley) 6/9/95";
#else
-__RCSID("$NetBSD: input.c,v 1.48 2016/03/27 14:34:46 christos Exp $");
+__RCSID("$NetBSD: input.c,v 1.49 2016/05/02 01:46:31 christos Exp $");
#endif
#endif /* not lint */
@@ -411,14 +411,13 @@ setinputfile(const char *fname, int push
error("Cannot rewind the file %s", fname);
}
- if (fd < 10) {
- fd2 = copyfd(fd, 10, 0, 0);
- close(fd);
- if (fd2 < 0)
- error("Out of file descriptors");
- fd = fd2;
+ fd2 = to_upper_fd(fd); /* closes fd, returns higher equiv */
+ if (fd2 == fd) {
+ (void) close(fd);
+ error("Out of file descriptors");
}
- setinputfd(fd, push);
+
+ setinputfd(fd2, push);
INTON;
}
Index: src/bin/sh/jobs.c
diff -u src/bin/sh/jobs.c:1.75 src/bin/sh/jobs.c:1.76
--- src/bin/sh/jobs.c:1.75 Sat Aug 22 08:12:47 2015
+++ src/bin/sh/jobs.c Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: jobs.c,v 1.75 2015/08/22 12:12:47 christos Exp $ */
+/* $NetBSD: jobs.c,v 1.76 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95";
#else
-__RCSID("$NetBSD: jobs.c,v 1.75 2015/08/22 12:12:47 christos Exp $");
+__RCSID("$NetBSD: jobs.c,v 1.76 2016/05/02 01:46:31 christos Exp $");
#endif
#endif /* not lint */
@@ -161,15 +161,7 @@ setjobctl(int on)
if (i == 3)
goto out;
}
- /* Move to a high fd */
- for (i = 10; i > 2; i--) {
- if ((err = fcntl(ttyfd, F_DUPFD, (1 << i) - 1)) != -1)
- break;
- }
- if (err != -1) {
- close(ttyfd);
- ttyfd = err;
- }
+ ttyfd = to_upper_fd(ttyfd); /* Move to a high fd */
#ifdef FIOCLEX
err = ioctl(ttyfd, FIOCLEX, 0);
#elif FD_CLOEXEC
Index: src/bin/sh/parser.c
diff -u src/bin/sh/parser.c:1.116 src/bin/sh/parser.c:1.117
--- src/bin/sh/parser.c:1.116 Mon Apr 4 08:39:08 2016
+++ src/bin/sh/parser.c Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: parser.c,v 1.116 2016/04/04 12:39:08 christos Exp $ */
+/* $NetBSD: parser.c,v 1.117 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95";
#else
-__RCSID("$NetBSD: parser.c,v 1.116 2016/04/04 12:39:08 christos Exp $");
+__RCSID("$NetBSD: parser.c,v 1.117 2016/05/02 01:46:31 christos Exp $");
#endif
#endif /* not lint */
@@ -50,7 +50,6 @@ __RCSID("$NetBSD: parser.c,v 1.116 2016/
#include "nodes.h"
#include "expand.h" /* defines rmescapes() */
#include "eval.h" /* defines commandname */
-#include "redir.h" /* defines copyfd() */
#include "syntax.h"
#include "options.h"
#include "input.h"
Index: src/bin/sh/redir.c
diff -u src/bin/sh/redir.c:1.42 src/bin/sh/redir.c:1.43
--- src/bin/sh/redir.c:1.42 Sat Mar 12 20:22:42 2016
+++ src/bin/sh/redir.c Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: redir.c,v 1.42 2016/03/13 01:22:42 christos Exp $ */
+/* $NetBSD: redir.c,v 1.43 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)redir.c 8.2 (Berkeley) 5/4/95";
#else
-__RCSID("$NetBSD: redir.c,v 1.42 2016/03/13 01:22:42 christos Exp $");
+__RCSID("$NetBSD: redir.c,v 1.43 2016/05/02 01:46:31 christos Exp $");
#endif
#endif /* not lint */
@@ -76,9 +76,16 @@ __RCSID("$NetBSD: redir.c,v 1.42 2016/03
MKINIT
+struct renamelist {
+ struct renamelist *next;
+ int orig;
+ int into;
+};
+
+MKINIT
struct redirtab {
struct redirtab *next;
- short renamed[10];
+ struct renamelist *renamed;
};
@@ -88,12 +95,64 @@ MKINIT struct redirtab *redirlist;
* We keep track of whether or not fd0 has been redirected. This is for
* background commands, where we want to redirect fd0 to /dev/null only
* if it hasn't already been redirected.
-*/
-int fd0_redirected = 0;
+ */
+STATIC int fd0_redirected = 0;
+/*
+ * And also where to put internal use fds that should be out of the
+ * way of user defined fds (normally)
+ */
+STATIC int big_sh_fd = 0;
+
+STATIC const struct renamelist *is_renamed(const struct renamelist *, int);
+STATIC void fd_rename(struct redirtab *, int, int);
+STATIC void free_rl(struct redirtab *, int);
STATIC void openredirect(union node *, char[10], int);
STATIC int openhere(const union node *);
+STATIC void find_big_fd(void);
+
+STATIC const struct renamelist *
+is_renamed(const struct renamelist *rl, int fd)
+{
+ while (rl != NULL) {
+ if (rl->orig == fd)
+ return rl;
+ rl = rl->next;
+ }
+ return NULL;
+}
+
+STATIC void
+free_rl(struct redirtab *rt, int reset)
+{
+ struct renamelist *rl, *rn = rt->renamed;
+
+ while ((rl = rn) != NULL) {
+ rn = rl->next;
+ if (rl->orig == 0)
+ fd0_redirected--;
+ if (reset) {
+ if (rl->into < 0)
+ close(rl->orig);
+ else
+ movefd(rl->into, rl->orig);
+ }
+ ckfree(rl);
+ }
+ rt->renamed = NULL;
+}
+STATIC void
+fd_rename(struct redirtab *rt, int from, int to)
+{
+ struct renamelist *rl = ckmalloc(sizeof(struct renamelist));
+
+ rl->next = rt->renamed;
+ rt->renamed = rl;
+
+ rl->orig = from;
+ rl->into = to;
+}
/*
* Process a list of redirection commands. If the REDIR_PUSH flag is set,
@@ -120,32 +179,45 @@ redirect(union node *redir, int flags)
* flags & REDIR_PUSH is never true if REDIR_VFORK is set.
*/
sv = ckmalloc(sizeof (struct redirtab));
- for (i = 0 ; i < 10 ; i++)
- sv->renamed[i] = EMPTY;
+ sv->renamed = NULL;
sv->next = redirlist;
redirlist = sv;
}
for (n = redir ; n ; n = n->nfile.next) {
fd = n->nfile.fd;
if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
- n->ndup.dupfd == fd)
- continue; /* redirect from/to same file descriptor */
+ n->ndup.dupfd == fd) {
+ /* redirect from/to same file descriptor */
+ fcntl(fd, F_SETFD, 0); /* make sure it stays open */
+ continue;
+ }
- if ((flags & REDIR_PUSH) && sv->renamed[fd] == EMPTY) {
+ if ((flags & REDIR_PUSH) && !is_renamed(sv->renamed, fd)) {
INTOFF;
- if ((i = fcntl(fd, F_DUPFD, 10)) == -1) {
+ if (big_sh_fd < 10)
+ find_big_fd();
+ if ((i = fcntl(fd, F_DUPFD, big_sh_fd)) == -1) {
switch (errno) {
case EBADF:
i = CLOSED;
break;
+ case EMFILE:
+ case EINVAL:
+ find_big_fd();
+ i = fcntl(fd, F_DUPFD, big_sh_fd);
+ if (i >= 0)
+ break;
+ /* FALLTHRU */
default:
- INTON;
- error("%d: %s", fd, strerror(errno));
+ i = errno;
+ INTON; /* XXX not needed here ? */
+ error("%d: %s", fd, strerror(i));
/* NOTREACHED */
}
- } else
+ }
+ if (i >= 0)
(void)fcntl(i, F_SETFD, FD_CLOEXEC);
- sv->renamed[fd] = i;
+ fd_rename(sv, fd, i);
INTON;
} else {
close(fd);
@@ -176,7 +248,8 @@ openredirect(union node *redir, char mem
* an open of a device or a fifo can block indefinitely.
*/
INTOFF;
- memory[fd] = 0;
+ if (fd < 10)
+ memory[fd] = 0;
switch (redir->nfile.type) {
case NFROM:
fname = redir->nfile.expfname;
@@ -227,7 +300,8 @@ openredirect(union node *redir, char mem
case NTOFD:
case NFROMFD:
if (redir->ndup.dupfd >= 0) { /* if not ">&-" */
- if (memory[redir->ndup.dupfd])
+ if (fd < 10 && redir->ndup.dupfd < 10 &&
+ memory[redir->ndup.dupfd])
memory[fd] = 1;
else
copyfd(redir->ndup.dupfd, fd, 1,
@@ -312,20 +386,9 @@ void
popredir(void)
{
struct redirtab *rp = redirlist;
- int i;
- for (i = 0 ; i < 10 ; i++) {
- if (rp->renamed[i] != EMPTY) {
- if (i == 0)
- fd0_redirected--;
- close(i);
- if (rp->renamed[i] >= 0) {
- copyfd(rp->renamed[i], i, 1, 0);
- close(rp->renamed[i]);
- }
- }
- }
INTOFF;
+ free_rl(rp, 1);
redirlist = rp->next;
ckfree(rp);
INTON;
@@ -352,7 +415,8 @@ SHELLPROC {
/* Return true if fd 0 has already been redirected at least once. */
int
-fd0_redirected_p (void) {
+fd0_redirected_p(void)
+{
return fd0_redirected != 0;
}
@@ -364,16 +428,14 @@ void
clearredir(int vforked)
{
struct redirtab *rp;
- int i;
+ struct renamelist *rl;
for (rp = redirlist ; rp ; rp = rp->next) {
- for (i = 0 ; i < 10 ; i++) {
- if (rp->renamed[i] >= 0) {
- close(rp->renamed[i]);
- }
- if (!vforked)
- rp->renamed[i] = EMPTY;
- }
+ if (!vforked)
+ free_rl(rp, 0);
+ else for (rl = rp->renamed; rl; rl = rl->next)
+ if (rl->into >= 0)
+ close(rl->into);
}
}
@@ -409,3 +471,60 @@ copyfd(int from, int to, int equal, int
}
return newfd;
}
+
+int
+movefd(int from, int to)
+{
+ if (from == to)
+ return to;
+
+ (void) close(to);
+ if (copyfd(from, to, 1, 0) != to)
+ error("Unable to make fd %d", to);
+ (void) close(from);
+
+ return to;
+}
+
+STATIC void
+find_big_fd(void)
+{
+ int i, fd;
+
+ for (i = (1 << 10); i >= 10; i >>= 1) {
+ if ((fd = fcntl(0, F_DUPFD, i - 1)) >= 0) {
+ close(fd);
+ break;
+ }
+ }
+
+ fd = (i / 5) * 4;
+ if ((i - fd) > 100)
+ fd = i - 100;
+ else if (fd < 10)
+ fd = 10;
+
+ big_sh_fd = fd;
+}
+
+int
+to_upper_fd(int fd)
+{
+ int i;
+
+ if (big_sh_fd < 10)
+ find_big_fd();
+ do {
+ i = fcntl(fd, F_DUPFD, big_sh_fd);
+ if (i >= 0) {
+ if (fd != i)
+ close(fd);
+ return i;
+ }
+ if (errno != EMFILE)
+ break;
+ find_big_fd();
+ } while (big_sh_fd > 10);
+
+ return fd;
+}
Index: src/bin/sh/redir.h
diff -u src/bin/sh/redir.h:1.18 src/bin/sh/redir.h:1.19
--- src/bin/sh/redir.h:1.18 Sat Mar 12 16:35:13 2016
+++ src/bin/sh/redir.h Sun May 1 21:46:31 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: redir.h,v 1.18 2016/03/12 21:35:13 christos Exp $ */
+/* $NetBSD: redir.h,v 1.19 2016/05/02 01:46:31 christos Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -46,4 +46,7 @@ void popredir(void);
int fd0_redirected_p(void);
void clearredir(int);
int copyfd(int, int, int, int);
+int movefd(int, int);
+int to_upper_fd(int);
+extern int big_sh_fd;
