From 8c24af9dcfe0d89a660c39838eec4d20bc13efbf Mon Sep 17 00:00:00 2001 From: Harald van Dijk Date: Tue, 22 May 2018 17:34:31 +0200 Subject: [PATCH] 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 Signed-off-by: Denys Vlasenko --- archival/cpio.c | 2 +- archival/libarchive/data_extract_all.c | 16 +++++++--------- archival/libarchive/get_header_ar.c | 2 +- archival/libarchive/unsafe_symlink_target.c | 21 +++++++++++---------- archival/tar.c | 2 +- archival/unzip.c | 7 ++++--- include/bb_archive.h | 11 ++++++----- testsuite/tar.tests | 16 ++++++++++++++++ 8 files changed, 47 insertions(+), 30 deletions(-) diff --git a/archival/cpio.c b/archival/cpio.c index 308ec1b25..221667112 100644 --- 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 8fa69ffaf..4c95db4a6 100644 --- 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 adcde46d5..7ce9c615c 100644 --- 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 8dcafeaa1..f8dc8033d 100644 --- 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 a8b888fa9..ae1ccc756 100644 --- 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 0d00d8dc9..96b7ab69b 100644 --- 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 0252488bf..2ee30f794 100644 --- 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 1675b07b1..6c479d3fe 100755 --- 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