@matheusbsbs / matheus-bagliano / commits / 82a46af13e

archive-tar: fix pax extended header length calculation

A pax extended header record starts with a decimal number. Its value is the length of the whole record, including its own length. The calculation of that number in strbuf_append_ext_header() is off by one in case the length of the rest is close to a higher order of magnitude. This affects paths and link targets a bit shorter than 1000, 10000, 100000 etc. characters -- paths with a length of up to 100 fit into the tar header and don't need a pax extended header. The mistake has been present since the function was added by ae64bbc18c ("tar-tree: Introduce write_entry()", 2006-03-25). Account for digits added to len during the loop and keep incrementing until we have enough space for len and the rest. The crucial change is to check against the current value of len before each iteration, instead of against its value before the loop. Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>

René Scharfe committed Aug 17, 2019 at 18:24 UTC 82a46af13eeed4b73a077b50edb90f559460267f

2 files changed +2 -2

archive-tar.c

+1 -1

@@ -149,7 +149,7 @@ static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,

149

150 /* "%u %s=%s\n" */

151 len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;

152 - for (tmp = len; tmp > 9; tmp /= 10)

152 + for (tmp = 1; len / 10 >= tmp; tmp *= 10)

153 len++;

154

155 strbuf_grow(sb, len);

t/t5004-archive-corner-cases.sh

+1 -1

@@ -217,7 +217,7 @@ build_tree() {

217 ' "$1"

218 }

219

220 -test_expect_failure 'tar archive with long paths' '

220 +test_expect_success 'tar archive with long paths' '

221 blob=$(echo foo | git hash-object -w --stdin) &&

222 tree=$(build_tree $blob | git mktree) &&

223 git archive -o long_paths.tar $tree 2>stderr &&