libarchive: do not extract unsafe symlinks unless $EXTRACT_UNSAFE_SYMLINKS=1

function                                             old     new   delta
unsafe_symlink_target                                  -     147    +147
unzip_main                                          2711    2732     +21
copy_file                                           1657    1678     +21
tar_main                                             999     971     -28
data_extract_all                                    1038     984     -54
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 2/2 up/down: 189/-82)           Total: 107 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 0 insertions, 19 deletions

diff --git a/archival/tar.c b/archival/tar.c
index 73c14ca81..9a5bcc7fe 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -278,23 +278,6 @@ static void chksum_and_xwrite(int fd, struct tar_header_t* hp)
         xwrite(fd, hp, sizeof(*hp));
 }
 
-static void replace_symlink_placeholders(llist_t *list)
-{
-        while (list) {
-                char *target;
-
-                target = list->data + strlen(list->data) + 1;
-                if (symlink(target, list->data)) {
-                        /* shared message */
-                        bb_error_msg_and_die("can't create %slink '%s' to '%s'",
-                                "sym",
-                                list->data, target
-                        );
-                }
-                list = list->link;
-        }
-}
-
 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 static void writeLongname(int fd, int type, const char *name, int dir)
 {
@@ -1255,8 +1238,6 @@ int tar_main(int argc UNUSED_PARAM, char **argv)
         while (get_header_tar(tar_handle) == EXIT_SUCCESS)
                 bb_got_signal = EXIT_SUCCESS; /* saw at least one header, good */
 
-        replace_symlink_placeholders(tar_handle->symlink_placeholders);
-
         /* Check that every file that should have been extracted was */
         while (tar_handle->accept) {
                 if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)