From 105ff10f12dce019ca2a455001239967c2e0e856 Mon Sep 17 00:00:00 2001

From: Jakub Filak <jfilak@redhat.com>

Date: Mon, 8 Dec 2014 16:02:11 +0100

Subject: [PATCH] ccpp-hook: move /proc/[pid]/ utils to libreport

Related to #548

Signed-off-by: Jakub Filak <jfilak@redhat.com>

---

 src/hooks/abrt-hook-ccpp.c | 202 +++++++++++++++------------------------------

 1 file changed, 66 insertions(+), 136 deletions(-)

diff --git a/src/hooks/abrt-hook-ccpp.c b/src/hooks/abrt-hook-ccpp.c

index f8f97ad..7fd9520 100644

--- a/src/hooks/abrt-hook-ccpp.c

+++ b/src/hooks/abrt-hook-ccpp.c

@@ -36,20 +36,6 @@

  */

 #define IGNORE_RESULT(func_call) do { if (func_call) /* nothing */; } while (0)

-static char* malloc_readlink(const char *linkname)

-{

-    char buf[PATH_MAX + 1];

-    int len;

-

-    len = readlink(linkname, buf, sizeof(buf)-1);

-    if (len >= 0)

-    {

-        buf[len] = '\0';

-        return xstrdup(buf);

-    }

-    return NULL;

-}

-

 /* Custom version of copyfd_xyz,

  * one which is able to write into two descriptors at once.

  */

@@ -171,75 +157,6 @@ static char *core_basename = (char*) "core";

  */

 static char *full_core_basename;

-

-static char* get_executable(pid_t pid, int *fd_p)

-{

-    char buf[sizeof("/proc/%lu/exe") + sizeof(long)*3];

-

-    sprintf(buf, "/proc/%lu/exe", (long)pid);

-    if (fd_p)

-        *fd_p = open(buf, O_RDONLY); /* might fail and return -1, it's ok */

-    char *executable = malloc_readlink(buf);

-    if (!executable)

-        return NULL;

-    /* find and cut off " (deleted)" from the path */

-    char *deleted = executable + strlen(executable) - strlen(" (deleted)");

-    if (deleted > executable && strcmp(deleted, " (deleted)") == 0)

-    {

-        *deleted = '\0';

-        log_info("File '%s' seems to be deleted", executable);

-    }

-    /* find and cut off prelink suffixes from the path */

-    char *prelink = executable + strlen(executable) - strlen(".#prelink#.XXXXXX");

-    if (prelink > executable && strncmp(prelink, ".#prelink#.", strlen(".#prelink#.")) == 0)

-    {

-        log_info("File '%s' seems to be a prelink temporary file", executable);

-        *prelink = '\0';

-    }

-    return executable;

-}

-

-static char* get_cwd(pid_t pid)

-{

-    char buf[sizeof("/proc/%lu/cwd") + sizeof(long)*3];

-    sprintf(buf, "/proc/%lu/cwd", (long)pid);

-    return malloc_readlink(buf);

-}

-

-static char* get_rootdir(pid_t pid)

-{

-    char buf[sizeof("/proc/%lu/root") + sizeof(long)*3];

-    sprintf(buf, "/proc/%lu/root", (long)pid);

-    return malloc_readlink(buf);

-}

-

-static int get_fsuid(char *proc_pid_status)

-{

-    int real, euid, saved;

-    /* if we fail to parse the uid, then make it root only readable to be safe */

-    int fs_uid = 0;

-

-    char *line = proc_pid_status; /* never NULL */

-    for (;;)

-    {

-        if (strncmp(line, "Uid", 3) == 0)

-        {

-            int n = sscanf(line, "Uid:\t%d\t%d\t%d\t%d\n", &real, &euid, &saved, &fs_uid);

-            if (n != 4)

-            {

-                perror_msg_and_die("Can't parse Uid: line");

-            }

-            break;

-        }

-        line = strchr(line, '\n');

-        if (!line)

-            break;

-        line++;

-    }

-

-    return fs_uid;

-}

-

 static int dump_suid_policy()

 {

     /*

@@ -400,42 +317,6 @@ static int open_user_core(uid_t uid, uid_t fsuid, pid_t pid, char **percent_valu

     return user_core_fd;

 }

-static bool dump_fd_info(const char *dest_filename, char *source_filename, int source_base_ofs)

-{

-    FILE *fp = fopen(dest_filename, "w");

-    if (!fp)

-        return false;

-

-    unsigned fd = 0;

-    while (fd <= 99999) /* paranoia check */

-    {

-        sprintf(source_filename + source_base_ofs, "fd/%u", fd);

-        char *name = malloc_readlink(source_filename);

-        if (!name)

-            break;

-        fprintf(fp, "%u:%s\n", fd, name);

-        free(name);

-

-        sprintf(source_filename + source_base_ofs, "fdinfo/%u", fd);

-        fd++;

-        FILE *in = fopen(source_filename, "r");

-        if (!in)

-            continue;

-        char buf[128];

-        while (fgets(buf, sizeof(buf)-1, in))

-        {

-            /* in case the line is not terminated, terminate it */

-            char *eol = strchrnul(buf, '\n');

-            eol[0] = '\n';

-            eol[1] = '\0';

-            fputs(buf, fp);

-        }

-        fclose(in);

-    }

-    fclose(fp);

-    return true;

-}

-

 /* Like xopen, but on error, unlocks and deletes dd and user core */

 static int create_or_die(const char *filename, int user_core_fd)

 {

@@ -513,6 +394,34 @@ static int test_configuration(bool setting_SaveFullCore, bool setting_CreateCore

     return 0;

 }

+int save_crashing_binary(pid_t pid, const char *dest_path, uid_t uid, gid_t gid)

+{

+    char buf[sizeof("/proc/%lu/exe") + sizeof(long)*3];

+

+    sprintf(buf, "/proc/%lu/exe", (long)pid);

+    int src_fd_binary = open(buf, O_RDONLY); /* might fail and return -1, it's ok */

+    if (src_fd_binary < 0)

+    {

+        log_notice("Failed to open an image of crashing binary");

+        return 0;

+    }

+

+    int dst_fd = open(dest_path, O_WRONLY | O_CREAT | O_TRUNC, DEFAULT_DUMP_DIR_MODE);

+    if (dst_fd < 0)

+    {

+        log_notice("Failed to create file '%s'", dest_path);

+        close(src_fd_binary);

+        return -1;

+    }

+

+    IGNORE_RESULT(fchown(dst_fd, uid, gid));

+

+    off_t sz = copyfd_eof(src_fd_binary, dst_fd, COPYFD_SPARSE);

+    close(src_fd_binary);

+

+    return fsync(dst_fd) != 0 || close(dst_fd) != 0 || sz < 0;

+}

+

 int main(int argc, char** argv)

 {

     /* Kernel starts us with all fd's closed.

@@ -612,8 +521,7 @@ int main(int argc, char** argv)

     char path[PATH_MAX];

-    int src_fd_binary = -1;

-    char *executable = get_executable(pid, setting_SaveBinaryImage ? &src_fd_binary : NULL);

+    char *executable = get_executable(pid);

     if (executable && strstr(executable, "/abrt-hook-ccpp"))

     {

         error_msg_and_die("PID %lu is '%s', not dumping it to avoid recursion",

@@ -628,6 +536,9 @@ int main(int argc, char** argv)

     uid_t fsuid = uid;

     uid_t tmp_fsuid = get_fsuid(proc_pid_status);

+    if (tmp_fsuid < 0)

+        perror_msg_and_die("Can't parse 'Uid: line' in /proc/%lu/status", (long)pid);

+

     int suid_policy = dump_suid_policy();

     if (tmp_fsuid != uid)

     {

@@ -805,16 +716,16 @@ int main(int argc, char** argv)

         dd_save_text(dd, FILENAME_ABRT_VERSION, VERSION);

-        if (src_fd_binary > 0)

+        if (setting_SaveBinaryImage)

         {

             strcpy(path + path_len, "/"FILENAME_BINARY);

-            int dst_fd = create_or_die(path, user_core_fd);

-            off_t sz = copyfd_eof(src_fd_binary, dst_fd, COPYFD_SPARSE);

-            if (fsync(dst_fd) != 0 || close(dst_fd) != 0 || sz < 0)

+

+            if (save_crashing_binary(pid, path, dd->dd_uid, dd->dd_gid))

             {

-                dd_delete(dd); error_msg_and_die("Error saving '%s'", path);

+                error_msg("Error saving '%s'", path);

+

+                goto error_exit;

             }

-            close(src_fd_binary);

         }

         off_t core_size = 0;

@@ -837,15 +748,12 @@ int main(int argc, char** argv)

             if (fsync(abrt_core_fd) != 0 || close(abrt_core_fd) != 0 || core_size < 0)

             {

                 unlink(path);

-                dd_delete(dd);

-                if (user_core_fd >= 0)

-                {

-                    xchdir(user_pwd);

-                    unlink(core_basename);

-                }

+

                 /* copyfd_sparse logs the error including errno string,

                  * but it does not log file name */

-                error_msg_and_die("Error writing '%s'", path);

+                error_msg("Error writing '%s'", path);

+

+                goto error_exit;

             }

             if (user_core_fd >= 0

                 /* error writing user coredump? */

@@ -865,6 +773,13 @@ int main(int argc, char** argv)

             create_user_core(user_core_fd, pid, ulimit_c);

         }

+        /* User core is either written or closed */

+        user_core_fd = -1;

+

+        /*

+         * ! No other errors should cause removal of the user core !

+         */

+

         /* Save JVM crash log if it exists. (JVM's coredump per se

          * is nearly useless for JVM developers)

          */

@@ -891,8 +806,9 @@ int main(int argc, char** argv)

                 off_t sz = copyfd_eof(src_fd, dst_fd, COPYFD_SPARSE);

                 if (close(dst_fd) != 0 || sz < 0)

                 {

-                    dd_delete(dd);

-                    error_msg_and_die("Error saving '%s'", path);

+                    error_msg("Error saving '%s'", path);

+

+                    goto error_exit;

                 }

                 close(src_fd);

             }

@@ -909,6 +825,8 @@ int main(int argc, char** argv)

          * Classic deadlock.

          */

         dd_close(dd);

+        dd = NULL;

+

         path[path_len] = '\0'; /* path now contains only directory name */

         char *newpath = xstrndup(path, path_len - (sizeof(".new")-1));

         if (rename(path, newpath) == 0)

@@ -938,4 +856,16 @@ int main(int argc, char** argv)

     /* We didn't create abrt dump, but may need to create compat coredump */

     return create_user_core(user_core_fd, pid, ulimit_c);

+

+error_exit:

+    if (dd)

+        dd_delete(dd);

+

+    if (user_core_fd >= 0)

+    {

+        xchdir(user_pwd);

+        unlink(core_basename);

+    }

+

+    xfunc_die();

 }

-- 

2.1.0