tar: fix interaction of delayed symlink and hardlink creation

function                                             old     new   delta
create_or_remember_link                                -     106    +106
create_links_from_list                                 -      93     +93
find_applet_by_name                                  124     128      +4
unzip_main                                          2724    2726      +2
data_extract_all                                     891     873     -18
create_symlinks_from_list                             64       -     -64
create_or_remember_symlink                            94       -     -94
------------------------------------------------------------------------------
(add/remove: 2/2 grow/shrink: 2/1 up/down: 205/-176)           Total: 29 bytes

Signed-off-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/archival/cpio.c b/archival/cpio.c
index 308ec1b254dd446823868f7b4a82bc0af00857b1..221667112d9f4dc36697bd025cbf65b4350f1986 100644 (file)
--- a/archival/cpio.c
+++ b/archival/cpio.c
@@ -508,7 +508,7 @@ int cpio_main(int argc UNUSED_PARAM, char **argv)
        while (get_header_cpio(archive_handle) == EXIT_SUCCESS)
                continue;
 
-       create_symlinks_from_list(archive_handle->symlink_placeholders);
+       create_links_from_list(archive_handle->link_placeholders);
 
        if (archive_handle->cpio__blocks != (off_t)-1
         && !(opt & OPT_QUIET)

diff --git a/archival/libarchive/data_extract_all.c b/archival/libarchive/data_extract_all.c
index 8fa69ffafc1cfc4186659705a16c6f6f49b23a92..4c95db4a66dfbe2f171c81664bd4b0293471160c 100644 (file)
--- a/archival/libarchive/data_extract_all.c
+++ b/archival/libarchive/data_extract_all.c
@@ -122,13 +122,10 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
 
        /* Handle hard links separately */
        if (hard_link) {
-               res = link(hard_link, dst_name);
-               if (res != 0) {
-                       /* shared message */
-                       bb_perror_msg("can't create %slink '%s' to '%s'",
-                               "hard", dst_name, hard_link
-                       );
-               }
+               create_or_remember_link(&archive_handle->link_placeholders,
+                               hard_link,
+                               dst_name,
+                               1);
                /* Hardlinks have no separate mode/ownership, skip chown/chmod */
                goto ret;
        }
@@ -195,9 +192,10 @@ void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
                 *
                 * Untarring bug.tar would otherwise place evil.py in '/tmp'.
                 */
-               create_or_remember_symlink(&archive_handle->symlink_placeholders,
+               create_or_remember_link(&archive_handle->link_placeholders,
                                file_header->link_target,
-                               dst_name);
+                               dst_name,
+                               0);
                break;
        case S_IFSOCK:
        case S_IFBLK:

diff --git a/archival/libarchive/get_header_ar.c b/archival/libarchive/get_header_ar.c
index adcde46d57f6b5e4eaaa01d40f7d0a2942bd0c8b..7ce9c615c69661bd6f9b5055390cab4cf3b74a5e 100644 (file)
--- a/archival/libarchive/get_header_ar.c
+++ b/archival/libarchive/get_header_ar.c
@@ -126,7 +126,7 @@ char FAST_FUNC get_header_ar(archive_handle_t *archive_handle)
                        struct archive_handle_t *sa = archive_handle->dpkg__sub_archive;
                        while (archive_handle->dpkg__action_data_subarchive(sa) == EXIT_SUCCESS)
                                continue;
-                       create_symlinks_from_list(sa->symlink_placeholders);
+                       create_links_from_list(sa->link_placeholders);
                } else
 #endif
                        archive_handle->action_data(archive_handle);

diff --git a/archival/libarchive/unsafe_symlink_target.c b/archival/libarchive/unsafe_symlink_target.c
index 8dcafeaa1b2ef99466a2288272ed7678b8027f28..f8dc8033d24fad73935678fd298106599589990d 100644 (file)
--- a/archival/libarchive/unsafe_symlink_target.c
+++ b/archival/libarchive/unsafe_symlink_target.c
@@ -5,13 +5,14 @@
 #include "libbb.h"
 #include "bb_archive.h"
 
-void FAST_FUNC create_or_remember_symlink(llist_t **symlink_placeholders,
+void FAST_FUNC create_or_remember_link(llist_t **link_placeholders,
                const char *target,
-               const char *linkname)
+               const char *linkname,
+               int hard_link)
 {
-       if (target[0] == '/' || strstr(target, "..")) {
-               llist_add_to(symlink_placeholders,
-                       xasprintf("%s%c%s", linkname, '\0', target)
+       if (hard_link || target[0] == '/' || strstr(target, "..")) {
+               llist_add_to_end(link_placeholders,
+                       xasprintf("%c%s%c%s", hard_link, linkname, '\0', target)
                );
                return;
        }
@@ -23,17 +24,17 @@ void FAST_FUNC create_or_remember_symlink(llist_t **symlink_placeholders,
        }
 }
 
-void FAST_FUNC create_symlinks_from_list(llist_t *list)
+void FAST_FUNC create_links_from_list(llist_t *list)
 {
        while (list) {
                char *target;
 
-               target = list->data + strlen(list->data) + 1;
-               if (symlink(target, list->data)) {
+               target = list->data + 1 + strlen(list->data + 1) + 1;
+               if ((*list->data ? link : symlink) (target, list->data + 1)) {
                        /* shared message */
                        bb_error_msg_and_die("can't create %slink '%s' to '%s'",
-                               "sym",
-                               list->data, target
+                               *list->data ? "hard" : "sym",
+                               list->data + 1, target
                        );
                }
                list = list->link;

diff --git a/archival/tar.c b/archival/tar.c
index a8b888fa9b21702a6af6fd9c885894e7e5ad794d..ae1ccc756c86510638b3ed82985c6a8667699ebc 100644 (file)
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -1244,7 +1244,7 @@ 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 */
 
-       create_symlinks_from_list(tar_handle->symlink_placeholders);
+       create_links_from_list(tar_handle->link_placeholders);
 
        /* Check that every file that should have been extracted was */
        while (tar_handle->accept) {

diff --git a/archival/unzip.c b/archival/unzip.c
index 0d00d8dc921ff129051b688bea02b1094a0d39f6..96b7ab69b403b2a543879ea5673d8a5cb217b7a1 100644 (file)
--- a/archival/unzip.c
+++ b/archival/unzip.c
@@ -372,9 +372,10 @@ static void unzip_extract_symlink(llist_t **symlink_placeholders,
                target[xstate.mem_output_size] = '\0';
 #endif
        }
-       create_or_remember_symlink(symlink_placeholders,
+       create_or_remember_link(symlink_placeholders,
                        target,
-                       dst_fn);
+                       dst_fn,
+                       0);
        free(target);
 }
 #endif
@@ -990,7 +991,7 @@ int unzip_main(int argc, char **argv)
        }
 
 #if ENABLE_FEATURE_UNZIP_CDF
-       create_symlinks_from_list(symlink_placeholders);
+       create_links_from_list(symlink_placeholders);
 #endif
 
        if ((opts & OPT_l) && quiet <= 1) {

diff --git a/include/bb_archive.h b/include/bb_archive.h
index 0252488bf38e826750a44a0a0bb07afdc6f525f3..2ee30f794f55e51c0320e38657e65e532956d5af 100644 (file)
--- a/include/bb_archive.h
+++ b/include/bb_archive.h
@@ -64,8 +64,8 @@ typedef struct archive_handle_t {
        /* Currently processed file's header */
        file_header_t *file_header;
 
-       /* List of symlink placeholders */
-       llist_t *symlink_placeholders;
+       /* List of link placeholders */
+       llist_t *link_placeholders;
 
        /* Process the header component, e.g. tar -t */
        void FAST_FUNC (*action_header)(const file_header_t *);
@@ -203,10 +203,11 @@ void seek_by_jump(int fd, off_t amount) FAST_FUNC;
 void seek_by_read(int fd, off_t amount) FAST_FUNC;
 
 const char *strip_unsafe_prefix(const char *str) FAST_FUNC;
-void create_or_remember_symlink(llist_t **symlink_placeholders,
+void create_or_remember_link(llist_t **link_placeholders,
                const char *target,
-               const char *linkname) FAST_FUNC;
-void create_symlinks_from_list(llist_t *list) FAST_FUNC;
+               const char *linkname,
+               int hard_link) FAST_FUNC;
+void create_links_from_list(llist_t *list) FAST_FUNC;
 
 void data_align(archive_handle_t *archive_handle, unsigned boundary) FAST_FUNC;
 const llist_t *find_list_entry(const llist_t *list, const char *filename) FAST_FUNC;

diff --git a/testsuite/tar.tests b/testsuite/tar.tests
index 1675b07b14e0f761bc3cb8e7e5c15fe1959e8291..6c479d3fe34b61e53f9f0bc671eed95100f584f7 100755 (executable)
--- a/testsuite/tar.tests
+++ b/testsuite/tar.tests
@@ -365,4 +365,20 @@ n8fYaKlioCTzL2oXYczyUUIP4u5IpwoSEwWdtoA=
 SKIP=
 cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
 
+mkdir tar.tempdir && cd tar.tempdir || exit 1
+testing "Symlinks and hardlinks coexist" '\
+mkdir dir
+>dir/a
+ln -s ../dir/a dir/b
+ln dir/b dir/c
+mkdir new
+tar cf - dir/* | tar -C new -xvf - 2>&1
+' "\
+dir/a
+dir/b
+dir/c
+" \
+"" ""
+cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
+
 exit $FAILCOUNT