From 239c4f7d1f47265526b39ad70106767d00805277 Mon Sep 17 00:00:00 2001

From: Jakub Filak <jfilak@redhat.com>

Date: Thu, 23 Apr 2015 13:30:15 +0200

Subject: [LIBREPORT PATCH] dd: harden functions against directory traversal

 issues

Test correctness of all accessed dump dir files in all dd* functions.

Before this commit, the callers were allowed to pass strings like

"../../etc/shadow" in the filename argument of all dd* functions.

Related: #1214457

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

---

 src/lib/create_dump_dir.c | 19 ++++++++++++-------

 src/lib/dump_dir.c        | 22 ++++++++++++++++++++++

 2 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/src/lib/create_dump_dir.c b/src/lib/create_dump_dir.c

index 4f67523..989a50c 100644

--- a/src/lib/create_dump_dir.c

+++ b/src/lib/create_dump_dir.c

@@ -42,6 +42,12 @@ struct dump_dir *create_dump_dir_from_problem_data(problem_data_t *problem_data,

         return NULL;

     }

+    if (!str_is_correct_filename(type))

+    {

+        error_msg(_("'%s' is not correct file name"), FILENAME_ANALYZER);

+        return NULL;

+    }

+

     uid_t uid = (uid_t)-1L;

     char *uid_str = problem_data_get_content_or_NULL(problem_data, FILENAME_UID);

@@ -105,6 +111,12 @@ struct dump_dir *create_dump_dir_from_problem_data(problem_data_t *problem_data,

     g_hash_table_iter_init(&iter, problem_data);

     while (g_hash_table_iter_next(&iter, (void**)&name, (void**)&value))

     {

+        if (!str_is_correct_filename(name))

+        {

+            error_msg("Problem data field name contains disallowed chars: '%s'", name);

+            continue;

+        }

+

         if (value->flags & CD_FLAG_BIN)

         {

             char *dest = concat_path_file(dd->dd_dirname, name);

@@ -119,13 +131,6 @@ struct dump_dir *create_dump_dir_from_problem_data(problem_data_t *problem_data,

             continue;

         }

-        /* only files should contain '/' and those are handled earlier */

-        if (name[0] == '.' || strchr(name, '/'))

-        {

-            error_msg("Problem data field name contains disallowed chars: '%s'", name);

-            continue;

-        }

-

         dd_save_text(dd, name, value->content);

     }

diff --git a/src/lib/dump_dir.c b/src/lib/dump_dir.c

index 2a65100..0048faf 100644

--- a/src/lib/dump_dir.c

+++ b/src/lib/dump_dir.c

@@ -345,6 +345,9 @@ static inline struct dump_dir *dd_init(void)

 int dd_exist(const struct dump_dir *dd, const char *path)

 {

+    if (!str_is_correct_filename(path))

+        error_msg_and_die("Cannot test existence. '%s' is not a valid file name", path);

+

     char *full_path = concat_path_file(dd->dd_dirname, path);

     int ret = exist_file_dir(full_path);

     free(full_path);

@@ -1044,6 +1047,13 @@ char* dd_load_text_ext(const struct dump_dir *dd, const char *name, unsigned fla

 //    if (!dd->locked)

 //        error_msg_and_die("dump_dir is not opened"); /* bug */

+    if (!str_is_correct_filename(name))

+    {

+        error_msg("Cannot load text. '%s' is not a valid file name", name);

+        if (!(flags & DD_LOAD_TEXT_RETURN_NULL_ON_FAILURE))

+            xfunc_die();

+    }

+

     /* Compat with old abrt dumps. Remove in abrt-2.1 */

     if (strcmp(name, "release") == 0)

         name = FILENAME_OS_RELEASE;

@@ -1065,6 +1075,9 @@ void dd_save_text(struct dump_dir *dd, const char *name, const char *data)

     if (!dd->locked)

         error_msg_and_die("dump_dir is not opened"); /* bug */

+    if (!str_is_correct_filename(name))

+        error_msg_and_die("Cannot save text. '%s' is not a valid file name", name);

+

     char *full_path = concat_path_file(dd->dd_dirname, name);

     save_binary_file(full_path, data, strlen(data), dd->dd_uid, dd->dd_gid, dd->mode);

     free(full_path);

@@ -1075,6 +1088,9 @@ void dd_save_binary(struct dump_dir* dd, const char* name, const char* data, uns

     if (!dd->locked)

         error_msg_and_die("dump_dir is not opened"); /* bug */

+    if (!str_is_correct_filename(name))

+        error_msg_and_die("Cannot save binary. '%s' is not a valid file name", name);

+

     char *full_path = concat_path_file(dd->dd_dirname, name);

     save_binary_file(full_path, data, size, dd->dd_uid, dd->dd_gid, dd->mode);

     free(full_path);

@@ -1082,6 +1098,9 @@ void dd_save_binary(struct dump_dir* dd, const char* name, const char* data, uns

 long dd_get_item_size(struct dump_dir *dd, const char *name)

 {

+    if (!str_is_correct_filename(name))

+        error_msg_and_die("Cannot get item size. '%s' is not a valid file name", name);

+

     long size = -1;

     char *iname = concat_path_file(dd->dd_dirname, name);

     struct stat statbuf;

@@ -1106,6 +1125,9 @@ int dd_delete_item(struct dump_dir *dd, const char *name)

     if (!dd->locked)

         error_msg_and_die("dump_dir is not opened"); /* bug */

+    if (!str_is_correct_filename(name))

+        error_msg_and_die("Cannot delete item. '%s' is not a valid file name", name);

+

     char *path = concat_path_file(dd->dd_dirname, name);

     int res = unlink(path);

-- 

1.8.3.1