mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-07-25 03:50:29 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Work around Landlock output inode in compile.com

Browse source 
This change fixes Landlock Make so that only the output target file is
unveiled, rather than unveiling the directory that contains it. This
gives us a much stronger sandbox. It also helped identify problematic
build code in our repo that should have been using o/tmp instead.

Landlock isn't able to let us unveil files that don't exist. Even if
they do, then once a file is deleted, the sandboxing for it goes away.
This caused problems for Landlock Make because tools like GNU LD will
repeatedly delete and recreate the output file. This change uses the
compile.com wrapper to ensure on changes happen to the output inode.

New binary available on https://justine.lol/make/

Fixes #528
This commit is contained in:
Justine Tunney 2022-08-09 06:28:41 -07:00
parent c464f45692
commit 133c693650
33 changed files with 207 additions and 1346 deletions
Download patch file Download diff file Expand all files Collapse all files

50
third_party/make/job.c vendored
View file

@ -47,6 +47,24 @@ this program. If not, see <http://www.gnu.org/licenses/>. */
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/consts/map.h"
#include "libc/intrin/kprintf.h"
#include "libc/sysv/consts/o.h"
#include "libc/calls/struct/timeval.h"
#include "libc/x/x.h"
#include "libc/intrin/kprintf.h"
#include "libc/time/time.h"
#include "libc/calls/calls.h"
#include "libc/intrin/kprintf.h"
#include "libc/assert.h"
#include "libc/sysv/consts/pr.h"
#include "libc/calls/struct/bpf.h"
#include "libc/calls/struct/filter.h"
#include "libc/calls/struct/seccomp.h"
#include "libc/calls/struct/filter.h"
#include "libc/sysv/consts/pr.h"
#include "libc/sysv/consts/pr.h"
#include "libc/sysv/consts/audit.h"
#include "libc/sysv/consts/nrlinux.h"
#include "libc/macros.internal.h"
#include "third_party/make/dep.h"
#define GOTO_SLOW \
@ -1781,14 +1799,34 @@ child_execute_job (struct childbase *child, int good_stdin, char **argv)
".runit.psk"),
"r");
/* unveil target output directory */
/*
* unveils target output file
*
* landlock operates per inode so it can't whitelist missing
* paths. so we create the output file manually, and prevent
* creation so that it can't be deleted by the command which
* must truncate when writing its output.
*/
if (strlen(c->file->name) < PATH_MAX)
{
const char *dir;
int fd, rc, err = errno;
strcpy (outpathbuf, c->file->name);
dir = dirname (outpathbuf);
makedirs (dir, 0755);
Unveil (dir, "rwc");
if (makedirs (dirname (outpathbuf), 0777) == -1)
errno = err;
fd = open (c->file->name, O_RDWR | O_CREAT, 0777);
if (fd != -1)
{
futimens (fd, (struct timespec[2]){0});
close (fd);
}
else if (errno == EEXIST)
errno = err;
else
OSS (error, NILF, "%s: touch target failed %s",
c->file->name, strerror (errno));
if (unveil (c->file->name, "rwx") && errno != ENOSYS)
OSS (error, NILF, "%s: unveil target failed %s",
c->file->name, strerror (errno));
}
/* unveil target prerequisites */
@ -1838,7 +1876,7 @@ exec_command (char **argv, char **envp)
/* Run the program. */
environ = envp;
execvp (argv[0], argv);
execv (argv[0], argv);
if(errno == ENOENT)
OSS (error, NILF, "%s: %s", argv[0], strerror (errno));