Revert "rexec: handle legacy kernels"

Broke Android

This reverts commit 8f350e637c0e8001398602a6b2f536de3905787d.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

diff --git a/src/lxc/file_utils.c b/src/lxc/file_utils.c
index c057cb5d2561b1beefc15569340b6902e75f3487..930fd738a942464a1c8ec3a50f764c214ae3afab 100644 (file)
--- a/src/lxc/file_utils.c
+++ b/src/lxc/file_utils.c
@@ -222,7 +222,7 @@ int lxc_make_tmpfile(char *template, bool rm)
        mode_t msk;
 
        msk = umask(0022);
-       fd = mkostemp(template, O_CLOEXEC);
+       fd = mkstemp(template);
        umask(msk);
        if (fd < 0)
                return -1;
@@ -366,33 +366,3 @@ on_error:
 
        return NULL;
 }
-
-int fd_to_fd(int from, int to)
-{
-       for (;;) {
-               uint8_t buf[PATH_MAX];
-               uint8_t *p = buf;
-               ssize_t bytes_to_write;
-               ssize_t bytes_read;
-
-               bytes_read = lxc_read_nointr(from, buf, sizeof buf);
-               if (bytes_read < 0)
-                       return -1;
-               if (bytes_read == 0)
-                       break;
-
-               bytes_to_write = (size_t)bytes_read;
-               do {
-                       ssize_t bytes_written;
-
-                       bytes_written = lxc_write_nointr(to, p, bytes_to_write);
-                       if (bytes_written < 0)
-                               return -1;
-
-                       bytes_to_write -= bytes_written;
-                       p += bytes_written;
-               } while (bytes_to_write > 0);
-       }
-
-       return 0;
-}

diff --git a/src/lxc/file_utils.h b/src/lxc/file_utils.h
index cc8f69e1830133e2f132981cc26dffcc8213f385..fc2b7d8c108131ec914913365ce8527cfb3865e5 100644 (file)
--- a/src/lxc/file_utils.h
+++ b/src/lxc/file_utils.h
@@ -57,6 +57,5 @@ extern FILE *fopen_cloexec(const char *path, const char *mode);
 extern ssize_t lxc_sendfile_nointr(int out_fd, int in_fd, off_t *offset,
                                   size_t count);
 extern char *file_to_buf(char *path, size_t *length);
-extern int fd_to_fd(int from, int to);
 
 #endif /* __LXC_FILE_UTILS_H */

diff --git a/src/lxc/memory_utils.h b/src/lxc/memory_utils.h
index c1dafb441a45380dffe1851b3264034dbf9166d6..fdcfb5530108e7cfe09e2a5f5a36b51ec63f61cf 100644 (file)
--- a/src/lxc/memory_utils.h
+++ b/src/lxc/memory_utils.h
@@ -28,8 +28,6 @@
 #include <sys/types.h>
 #include <unistd.h>
 
-#include "macro.h"
-
 static inline void __auto_free__(void *p)
 {
        free(*(void **)p);
@@ -47,17 +45,13 @@ static inline void __auto_closedir__(DIR **d)
                closedir(*d);
 }
 
-#define close_prot_errno_disarm(fd) \
-       if (fd >= 0) {              \
-               int _e_ = errno;    \
-               close(fd);          \
-               errno = _e_;        \
-               fd = -EBADF;        \
-       }
-
 static inline void __auto_close__(int *fd)
 {
-       close_prot_errno_disarm(*fd);
+       if (*fd >= 0) {
+               int e = errno;
+               close(*fd);
+               errno = e;
+       }
 }
 
 #define __do_close_prot_errno __attribute__((__cleanup__(__auto_close__)))

diff --git a/src/lxc/rexec.c b/src/lxc/rexec.c
index 3b714a1fbc75a65180e4706aa2bd41439251a655..0589b4a781e1e56e16e4febd6c81f93f035db1fe 100644 (file)
--- a/src/lxc/rexec.c
+++ b/src/lxc/rexec.c
@@ -84,97 +84,42 @@ static int parse_argv(char ***argv)
 static int is_memfd(void)
 {
        __do_close_prot_errno int fd = -EBADF;
-       int seals;
+       int saved_errno, seals;
 
        fd = open("/proc/self/exe", O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                return -ENOTRECOVERABLE;
 
        seals = fcntl(fd, F_GET_SEALS);
-       if (seals < 0) {
-               struct stat s = {0};
-
-               if (fstat(fd, &s) == 0) {
-                       fprintf(stderr, "AAAAA: %ld\n", (long)s.st_nlink);
-                       return (s.st_nlink == 0);
-               }
-
+       if (seals < 0)
                return -EINVAL;
-       }
 
        return seals == LXC_MEMFD_REXEC_SEALS;
 }
 
 static void lxc_rexec_as_memfd(char **argv, char **envp, const char *memfd_name)
 {
-       __do_close_prot_errno int fd = -EBADF, memfd = -EBADF, tmpfd = -EBADF;
-       int ret;
+       __do_close_prot_errno int fd = -EBADF, memfd = -EBADF;
+       int saved_errno;
+       ssize_t bytes_sent;
 
        memfd = memfd_create(memfd_name, MFD_ALLOW_SEALING | MFD_CLOEXEC);
-       if (memfd < 0) {
-               char template[PATH_MAX];
-
-               ret = snprintf(template, sizeof(template),
-                              P_tmpdir "/.%s_XXXXXX", memfd_name);
-               if (ret < 0 || (size_t)ret >= sizeof(template))
-                       return;
-
-               tmpfd = lxc_make_tmpfile(template, true);
-               if (tmpfd < 0)
-                       return;
-
-               ret = fchmod(tmpfd, 0700);
-               if (ret)
-                       return;
-       }
+       if (memfd < 0)
+               return;
 
        fd = open("/proc/self/exe", O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                return;
 
        /* sendfile() handles up to 2GB. */
-       if (memfd >= 0) {
-               ssize_t bytes_sent = 0;
-               struct stat st = {0};
-
-               ret = fstat(fd, &st);
-               if (ret)
-                       return;
-
-               while (bytes_sent < st.st_size) {
-                       ssize_t sent;
-                       sent = lxc_sendfile_nointr(memfd, fd, NULL,
-                                                  st.st_size - bytes_sent);
-                       if (sent < 0)
-                               return;
-                       bytes_sent += sent;
-               }
-       } else if (fd_to_fd(fd, tmpfd)) {
+       bytes_sent = lxc_sendfile_nointr(memfd, fd, NULL, LXC_SENDFILE_MAX);
+       if (bytes_sent < 0)
                return;
-       }
 
-       close_prot_errno_disarm(fd);
-
-       if (memfd >= 0 && fcntl(memfd, F_ADD_SEALS, LXC_MEMFD_REXEC_SEALS))
+       if (fcntl(memfd, F_ADD_SEALS, LXC_MEMFD_REXEC_SEALS))
                return;
 
-       if (memfd >= 0) {
-               fexecve(memfd, argv, envp);
-       } else {
-               __do_close_prot_errno int execfd = -EBADF;
-               char procfd[LXC_PROC_PID_FD_LEN];
-
-               ret = snprintf(procfd, sizeof(procfd), "/proc/self/fd/%d", tmpfd);
-               if (ret < 0 || (size_t)ret >= sizeof(procfd))
-                       return;
-
-               execfd = open(procfd, O_PATH | O_CLOEXEC);
-               close_prot_errno_disarm(tmpfd);
-               if (execfd < 0)
-                       return;
-
-               fexecve(execfd, argv, envp);
-       }
+       fexecve(memfd, argv, envp);
 }
 
 /*