From fb8952077dfa11dc1534b5a9d965cbb39b043af4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ren=C3=A9=20Scharfe?= Date: Mon, 3 Sep 2018 14:49:26 +0000 Subject: [PATCH] fsck: use strbuf_getline() to read skiplist file MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The buffer is unlikely to contain a NUL character, so printing its contents using %s in a die() format is unsafe (detected with ASan). Use an idiomatic strbuf_getline() loop instead, which ensures the buffer is always NUL-terminated, supports CRLF files as well, accepts files without a newline after the last line, supports any hash length automatically, and is shorter. This fixes a bug where emitting an error about an invalid line on say line 1 would continue printing subsequent lines, and usually continue into uninitialized memory. The performance impact of this, on a CentOS 7 box with RedHat GCC 4.8.5-28: $ GIT_PERF_REPEAT_COUNT=5 GIT_PERF_MAKE_OPTS='-j56 CFLAGS="-O3"' ./run HEAD~ HEAD p1451-fsck-skip-list.sh Test HEAD~ HEAD ---------------------------------------------------------------------------------------- 1450.3: fsck with 0 skipped bad commits 7.75(7.39+0.35) 7.68(7.29+0.39) -0.9% 1450.5: fsck with 1 skipped bad commits 7.70(7.30+0.40) 7.80(7.42+0.37) +1.3% 1450.7: fsck with 10 skipped bad commits 7.77(7.37+0.40) 7.87(7.47+0.40) +1.3% 1450.9: fsck with 100 skipped bad commits 7.82(7.41+0.40) 7.88(7.43+0.44) +0.8% 1450.11: fsck with 1000 skipped bad commits 7.88(7.49+0.39) 7.84(7.43+0.40) -0.5% 1450.13: fsck with 10000 skipped bad commits 8.02(7.63+0.39) 8.07(7.67+0.39) +0.6% 1450.15: fsck with 100000 skipped bad commits 8.01(7.60+0.41) 8.08(7.70+0.38) +0.9% 1450.17: fsck with 1000000 skipped bad commits 7.60(7.10+0.50) 7.37(7.18+0.19) -3.0% Helped-by: Jeff King Signed-off-by: Rene Scharfe Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano --- fsck.c | 25 ++++++++++++------------- t/t5504-fetch-receive-strict.sh | 2 +- 2 files changed, 13 insertions(+), 14 deletions(-) diff --git a/fsck.c b/fsck.c index a0cee0be59..972a26b9ba 100644 --- a/fsck.c +++ b/fsck.c @@ -183,8 +183,9 @@ static int fsck_msg_type(enum fsck_msg_id msg_id, static void init_skiplist(struct fsck_options *options, const char *path) { static struct oid_array skiplist = OID_ARRAY_INIT; - int sorted, fd; - char buffer[GIT_MAX_HEXSZ + 1]; + int sorted; + FILE *fp; + struct strbuf sb = STRBUF_INIT; struct object_id oid; if (options->skiplist) @@ -194,25 +195,23 @@ static void init_skiplist(struct fsck_options *options, const char *path) options->skiplist = &skiplist; } - fd = open(path, O_RDONLY); - if (fd < 0) + fp = fopen(path, "r"); + if (!fp) die("Could not open skip list: %s", path); - for (;;) { + while (!strbuf_getline(&sb, fp)) { const char *p; - int result = read_in_full(fd, buffer, sizeof(buffer)); - if (result < 0) - die_errno("Could not read '%s'", path); - if (!result) - break; - if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') - die("Invalid SHA-1: %s", buffer); + if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0') + die("Invalid SHA-1: %s", sb.buf); oid_array_append(&skiplist, &oid); if (sorted && skiplist.nr > 1 && oidcmp(&skiplist.oid[skiplist.nr - 2], &oid) > 0) sorted = 0; } - close(fd); + if (ferror(fp)) + die_errno("Could not read '%s'", path); + fclose(fp); + strbuf_release(&sb); if (sorted) skiplist.sorted = 1; diff --git a/t/t5504-fetch-receive-strict.sh b/t/t5504-fetch-receive-strict.sh index 96bf9facbd..d67ab37321 100755 --- a/t/t5504-fetch-receive-strict.sh +++ b/t/t5504-fetch-receive-strict.sh @@ -185,7 +185,7 @@ test_expect_success 'fsck with invalid or bogus skipList input (comments & empty test_i18ngrep "^fatal: Invalid SHA-1: " err-with-empty-line ' -test_expect_failure 'fsck no garbage output from comments & empty lines errors' ' +test_expect_success 'fsck no garbage output from comments & empty lines errors' ' test_line_count = 1 err-with-comment && test_line_count = 1 err-with-empty-line ' -- 2.11.4.GIT