Fixes FS#18770, and hopefully an occasional deadlock in my frontend as well.
For simplicity it redirects all scriptlet output through SCRIPTLET_INFO, and
all callbacks in the child process have been replaced for thread-safety.

Signed-off-by: Jonathan Conder <[email protected]>
---
 lib/libalpm/util.c |   84 ++++++++++++++++++++++++++++++---------------------
 1 files changed, 49 insertions(+), 35 deletions(-)

diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c
index 2b006e2..c88be2d 100644
--- a/lib/libalpm/util.c
+++ b/lib/libalpm/util.c
@@ -462,6 +462,7 @@ int _alpm_run_chroot(const char *root, const char *cmd)
 {
        char cwd[PATH_MAX];
        pid_t pid;
+       int pipefd[2];
        int restore_cwd = 0;
        int retval = 0;
 
@@ -485,6 +486,12 @@ int _alpm_run_chroot(const char *root, const char *cmd)
        /* Flush open fds before fork() to avoid cloning buffers */
        fflush(NULL);
 
+       if(pipe(pipefd) == -1) {
+               _alpm_log(PM_LOG_ERROR, _("could not create pipe (%s)\n"), 
strerror(errno));
+               retval = 1;
+               goto cleanup;
+       }
+
        /* fork- parent and child each have seperate code blocks below */
        pid = fork();
        if(pid == -1) {
@@ -494,53 +501,60 @@ int _alpm_run_chroot(const char *root, const char *cmd)
        }
 
        if(pid == 0) {
-               FILE *pipe;
                /* this code runs for the child only (the actual chroot/exec) */
-               _alpm_log(PM_LOG_DEBUG, "chrooting in %s\n", root);
+               close(1);
+               close(2);
+               close(pipefd[0]);
+               while(dup2(pipefd[1], 1) == -1 && errno == EINTR);
+               while(dup2(pipefd[1], 2) == -1 && errno == EINTR);
+               close(pipefd[1]);
+
                if(chroot(root) != 0) {
-                       _alpm_log(PM_LOG_ERROR, _("could not change the root 
directory (%s)\n"),
-                                       strerror(errno));
+                       printf(_("could not change the root directory (%s)\n"), 
strerror(errno));
                        exit(1);
                }
                if(chdir("/") != 0) {
-                       _alpm_log(PM_LOG_ERROR, _("could not change directory 
to / (%s)\n"),
-                                       strerror(errno));
+                       printf(_("could not change directory to / (%s)\n"), 
strerror(errno));
                        exit(1);
                }
                umask(0022);
-               pipe = popen(cmd, "r");
-               if(!pipe) {
-                       _alpm_log(PM_LOG_ERROR, _("call to popen failed 
(%s)\n"),
-                                       strerror(errno));
-                       exit(1);
-               }
-               while(!feof(pipe)) {
-                       char line[PATH_MAX];
-                       if(fgets(line, PATH_MAX, pipe) == NULL)
-                               break;
-                       alpm_logaction("%s", line);
-                       EVENT(handle->trans, PM_TRANS_EVT_SCRIPTLET_INFO, line, 
NULL);
-               }
-               retval = pclose(pipe);
-               exit(WEXITSTATUS(retval));
+               execl("/bin/sh", "sh", "-c", cmd, (char *) NULL);
+               printf(_("call to execl failed (%s)\n"), strerror(errno));
+               exit(1);
        } else {
                /* this code runs for the parent only (wait on the child) */
-               pid_t retpid;
                int status;
-               while((retpid = waitpid(pid, &status, 0)) == -1 && errno == 
EINTR);
-               if(retpid == -1) {
-                       _alpm_log(PM_LOG_ERROR, _("call to waitpid failed 
(%s)\n"),
-                                 strerror(errno));
-                       retval = 1;
-                       goto cleanup;
+               FILE *pipe;
+
+               close(pipefd[1]);
+               pipe = fdopen(pipefd[0], "r");
+               if(pipe == NULL) {
+                       close(pipefd[0]);
                } else {
-                       /* check the return status, make sure it is 0 (success) 
*/
-                       if(WIFEXITED(status)) {
-                               _alpm_log(PM_LOG_DEBUG, "call to waitpid 
succeeded\n");
-                               if(WEXITSTATUS(status) != 0) {
-                                       _alpm_log(PM_LOG_ERROR, _("command 
failed to execute correctly\n"));
-                                       retval = 1;
-                               }
+                       while(!feof(pipe)) {
+                               char line[PATH_MAX];
+                               if(fgets(line, PATH_MAX, pipe) == NULL)
+                                       break;
+                               alpm_logaction("%s", line);
+                               EVENT(handle->trans, 
PM_TRANS_EVT_SCRIPTLET_INFO, line, NULL);
+                       }
+                       fclose(pipe);
+               }
+
+               while(waitpid(pid, &status, 0) == -1) {
+                       if(errno != EINTR) {
+                               _alpm_log(PM_LOG_ERROR, _("call to waitpid 
failed (%s)\n"), strerror(errno));
+                               retval = 1;
+                               goto cleanup;
+                       }
+               }
+
+               /* check the return status, make sure it is 0 (success) */
+               if(WIFEXITED(status)) {
+                       _alpm_log(PM_LOG_DEBUG, "call to waitpid succeeded\n");
+                       if(WEXITSTATUS(status) != 0) {
+                               _alpm_log(PM_LOG_ERROR, _("command failed to 
execute correctly\n"));
+                               retval = 1;
                        }
                }
        }
-- 
1.7.1



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