From 7340f67b9860ea0531c1450e5aa261c50f67165d Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Sat, 29 Oct 2016 21:04:40 -0700 Subject: [PATCH] When extracting, skip ".." members * NEWS: Document this. * src/extract.c (extract_archive): Skip members whose names contain "..". CVE: CVE-2016-6321 Upstream-Status: Backport Cherry picked from commit: 7340f67 When extracting, skip ".." members Signed-off-by: Sona Sarmadi --- NEWS | 8 +++++++- src/extract.c | 8 ++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/NEWS b/NEWS index 501164a..fc97cfc 100644 --- a/NEWS +++ b/NEWS @@ -1,6 +1,12 @@ -GNU tar NEWS - User visible changes. 2016-05-16 +GNU tar NEWS - User visible changes. 2016-10-29 Please send GNU tar bug reports to +* Member names containing '..' components are now skipped when extracting. + +This fixes tar's behavior to match its documentation, and is a bit +safer when extracting untrusted archives over old files (an unsafe +practice that the tar manual has long recommended against). + version 1.29 - Sergey Poznyakoff, 2016-05-16 diff --git a/src/extract.c b/src/extract.c index f982433..7904148 100644 --- a/src/extract.c +++ b/src/extract.c @@ -1629,12 +1629,20 @@ extract_archive (void) { char typeflag; tar_extractor_t fun; + bool skip_dotdot_name; fatal_exit_hook = extract_finish; set_next_block_after (current_header); + skip_dotdot_name = (!absolute_names_option + && contains_dot_dot (current_stat_info.orig_file_name)); + if (skip_dotdot_name) + ERROR ((0, 0, _("%s: Member name contains '..'"), + quotearg_colon (current_stat_info.orig_file_name))); + if (!current_stat_info.file_name[0] + || skip_dotdot_name || (interactive_option && !confirm ("extract", current_stat_info.file_name))) { -- 1.9.1