From 74c4de58329567b1927370db20278d1284f30a14 Mon Sep 17 00:00:00 2001 From: Eric Sunshine Date: Wed, 24 Dec 2014 04:43:16 -0500 Subject: [PATCH] checkout-index: fix --temp relative path mangling checkout-index --temp only properly prints relative paths which are descendants of the current directory. Paths in ancestor or sibling directories (or their children) are often printed in mangled form. For example: mkdir a bbb && >file && >bbb/file && git update-index --add file bbb/file && cd a && git checkout-index --temp ../file ../bbb/file prints: .merge_file_ooblek le .merge_file_igloo0 b/file rather than the correct: .merge_file_ooblek ../file .merge_file_igloo0 ../bbb/file Internally, given the above example, checkout-index prefixes each input argument with the name of the current directory ("a/", in this case), and then assumes that it can simply skip forward by strlen("a/") bytes to recover the original name. This works for files in the current directory or its descendants, but fails for files in ancestors or siblings (or their children) due to path normalization. For instance, given "../file", "a/" is prepended, giving "a/../file". Path normalization folds out "a/../", resulting in "file". Attempting to recover the original name by skipping strlen("a/") bytes gives the incorrect "le" rather than the desired "../file". Fix this by taking advantage of write_name_quoted_relative() to recover the original name properly, rather than assuming that it can be recovered by skipping strlen(prefix) bytes. As a bonus, this also fixes a bug in which checkout-index --temp accessed and printed memory beyond the end-of-string. For instance, within a subdirectory named "subdirectory", and given argument "../file", prefixing would give "subdirectory/../file", which would become "file" after normalization. checkout-index would then attempt to recover the original name by skipping strlen("subdirectory/") bytes of "file", which placed it well beyond end-of-string. Despite this error, it often appeared to give the correct result, but only due to an accident of implementation which left an apparently correct copy of the path in memory following the normalized value. In particular, handed "subdirectory/../file", in-place processing by normalize_path_copy_len() resulted in "file\0rectory/../file". When checkout-index skipped strlen("subdirectory/") bytes, it ended up back at "../file" and thus appeared to give the correct answer, despite being past end-of-string. Reported-by: Russ Cox Signed-off-by: Eric Sunshine Signed-off-by: Junio C Hamano --- builtin/checkout-index.c | 16 ++++++++-------- t/t2004-checkout-cache-temp.sh | 2 +- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/builtin/checkout-index.c b/builtin/checkout-index.c index 61e75eb60c..256310f629 100644 --- a/builtin/checkout-index.c +++ b/builtin/checkout-index.c @@ -18,7 +18,7 @@ static char topath[4][TEMPORARY_FILENAME_LENGTH + 1]; static struct checkout state; -static void write_tempfile_record(const char *name, int prefix_length) +static void write_tempfile_record(const char *name, const char *prefix) { int i; @@ -35,14 +35,14 @@ static void write_tempfile_record(const char *name, int prefix_length) fputs(topath[checkout_stage], stdout); putchar('\t'); - write_name_quoted(name + prefix_length, stdout, line_termination); + write_name_quoted_relative(name, prefix, stdout, line_termination); for (i = 0; i < 4; i++) { topath[i][0] = 0; } } -static int checkout_file(const char *name, int prefix_length) +static int checkout_file(const char *name, const char *prefix) { int namelen = strlen(name); int pos = cache_name_pos(name, namelen); @@ -71,7 +71,7 @@ static int checkout_file(const char *name, int prefix_length) if (did_checkout) { if (to_tempfile) - write_tempfile_record(name, prefix_length); + write_tempfile_record(name, prefix); return errs > 0 ? -1 : 0; } @@ -106,7 +106,7 @@ static void checkout_all(const char *prefix, int prefix_length) if (last_ce && to_tempfile) { if (ce_namelen(last_ce) != ce_namelen(ce) || memcmp(last_ce->name, ce->name, ce_namelen(ce))) - write_tempfile_record(last_ce->name, prefix_length); + write_tempfile_record(last_ce->name, prefix); } if (checkout_entry(ce, &state, to_tempfile ? topath[ce_stage(ce)] : NULL) < 0) @@ -114,7 +114,7 @@ static void checkout_all(const char *prefix, int prefix_length) last_ce = ce; } if (last_ce && to_tempfile) - write_tempfile_record(last_ce->name, prefix_length); + write_tempfile_record(last_ce->name, prefix); if (errs) /* we have already done our error reporting. * exit with the same code as die(). @@ -247,7 +247,7 @@ int cmd_checkout_index(int argc, const char **argv, const char *prefix) if (read_from_stdin) die("git checkout-index: don't mix '--stdin' and explicit filenames"); p = prefix_path(prefix, prefix_length, arg); - checkout_file(p, prefix_length); + checkout_file(p, prefix); if (p < arg || p > arg + strlen(arg)) free((char *)p); } @@ -267,7 +267,7 @@ int cmd_checkout_index(int argc, const char **argv, const char *prefix) strbuf_swap(&buf, &nbuf); } p = prefix_path(prefix, prefix_length, buf.buf); - checkout_file(p, prefix_length); + checkout_file(p, prefix); if (p < buf.buf || p > buf.buf + buf.len) free((char *)p); } diff --git a/t/t2004-checkout-cache-temp.sh b/t/t2004-checkout-cache-temp.sh index 3c2b2b9046..a12afe93f3 100755 --- a/t/t2004-checkout-cache-temp.sh +++ b/t/t2004-checkout-cache-temp.sh @@ -206,7 +206,7 @@ test_expect_success 'checkout --temp symlink' ' test $(cat $p) = path7 ' -test_expect_failure 'emit well-formed relative path' ' +test_expect_success 'emit well-formed relative path' ' rm -f path* .merge_* actual .git/index && >path0123456789 && git update-index --add path0123456789 && -- 2.11.4.GIT