In `do_write_index()`, we use a `struct hashfile` to write the index with a trailer hash. In case the write fails though, we never clean up the allocated `hashfile` state and thus leak memory.
Refactor the code to have a common exit path where we can free this and other allocated memory. While at it, refactor our use of `strbuf`s such that we reuse the same buffer to avoid some unneeded allocations.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
---
read-cache.c | 97 ++++++++++++++++++------------
t/t1601-index-bogus.sh | 2 +
t/t2107-update-index-basic.sh | 1 +
t/t7008-filter-branch-null-sha1.sh | 1 +
4 files changed, 62 insertions(+), 39 deletions(-)
Show changes to 4 files +62 −39
read-cache.c, t/t1601-index-bogus.sh, t/t2107-update-index-basic.sh, t/t7008-filter-branch-null-sha1.sh
diff --git a/read-cache.c b/read-cache.c
index 48bf24f87c..36821fe5b5 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -2840,8 +2840,9 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
int csum_fsync_flag;
int ieot_entries = 1;
struct index_entry_offset_table *ieot = NULL;
- int nr, nr_threads;
struct repository *r = istate->repo;
+ struct strbuf sb = STRBUF_INIT;
+ int nr, nr_threads, ret;
f = hashfd(tempfile->fd, tempfile->filename.buf);
@@ -2962,8 +2963,8 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
strbuf_release(&previous_name_buf);
if (err) {
- free(ieot);
- return err;
+ ret = err;
+ goto out;
}
offset = hashfile_total(f);
@@ -2985,20 +2986,20 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
* index.
*/
if (ieot) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
write_ieot_extension(&sb, ieot);
err = write_index_ext_header(f, eoie_c, CACHE_EXT_INDEXENTRYOFFSETTABLE, sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- free(ieot);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
if (write_extensions & WRITE_SPLIT_INDEX_EXTENSION &&
istate->split_index) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
if (istate->sparse_index)
die(_("cannot write split index for a sparse index"));
@@ -3007,59 +3008,66 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
write_index_ext_header(f, eoie_c, CACHE_EXT_LINK,
sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
if (write_extensions & WRITE_CACHE_TREE_EXTENSION &&
!drop_cache_tree && istate->cache_tree) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
cache_tree_write(&sb, istate->cache_tree);
err = write_index_ext_header(f, eoie_c, CACHE_EXT_TREE, sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
if (write_extensions & WRITE_RESOLVE_UNDO_EXTENSION &&
istate->resolve_undo) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
resolve_undo_write(&sb, istate->resolve_undo);
err = write_index_ext_header(f, eoie_c, CACHE_EXT_RESOLVE_UNDO,
sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
if (write_extensions & WRITE_UNTRACKED_CACHE_EXTENSION &&
istate->untracked) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
write_untracked_extension(&sb, istate->untracked);
err = write_index_ext_header(f, eoie_c, CACHE_EXT_UNTRACKED,
sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
if (write_extensions & WRITE_FSMONITOR_EXTENSION &&
istate->fsmonitor_last_update) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
write_fsmonitor_extension(&sb, istate);
err = write_index_ext_header(f, eoie_c, CACHE_EXT_FSMONITOR, sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
if (istate->sparse_index) {
- if (write_index_ext_header(f, eoie_c, CACHE_EXT_SPARSE_DIRECTORIES, 0) < 0)
- return -1;
+ if (write_index_ext_header(f, eoie_c, CACHE_EXT_SPARSE_DIRECTORIES, 0) < 0) {
+ ret = -1;
+ goto out;
+ }
}
/*
@@ -3069,14 +3077,15 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
* when loading the shared index.
*/
if (eoie_c) {
- struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
write_eoie_extension(&sb, eoie_c, offset);
err = write_index_ext_header(f, NULL, CACHE_EXT_ENDOFINDEXENTRIES, sb.len) < 0;
hashwrite(f, sb.buf, sb.len);
- strbuf_release(&sb);
- if (err)
- return -1;
+ if (err) {
+ ret = -1;
+ goto out;
+ }
}
csum_fsync_flag = 0;
@@ -3085,13 +3094,16 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
finalize_hashfile(f, istate->oid.hash, FSYNC_COMPONENT_INDEX,
CSUM_HASH_IN_STREAM | csum_fsync_flag);
+ f = NULL;
if (close_tempfile_gently(tempfile)) {
- error(_("could not close '%s'"), get_tempfile_path(tempfile));
- return -1;
+ ret = error(_("could not close '%s'"), get_tempfile_path(tempfile));
+ goto out;
+ }
+ if (stat(get_tempfile_path(tempfile), &st)) {
+ ret = -1;
+ goto out;
}
- if (stat(get_tempfile_path(tempfile), &st))
- return -1;
istate->timestamp.sec = (unsigned int)st.st_mtime;
istate->timestamp.nsec = ST_MTIME_NSEC(st);
trace_performance_since(start, "write index, changed mask = %x", istate->cache_changed);
@@ -3105,7 +3117,14 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,
trace2_data_intmax("index", the_repository, "write/cache_nr",
istate->cache_nr);
- return 0;
+ ret = 0;
+
+out:
+ if (f)
+ free_hashfile(f);
+ strbuf_release(&sb);
+ free(ieot);
+ return ret;
}
void set_alternate_index_output(const char *name)
diff --git a/t/t1601-index-bogus.sh b/t/t1601-index-bogus.sh
index 4171f1e141..5dcc101882 100755
--- a/t/t1601-index-bogus.sh
+++ b/t/t1601-index-bogus.sh
@@ -1,6 +1,8 @@
#!/bin/sh
test_description='test handling of bogus index entries'
+
+TEST_PASSES_SANITIZE_LEAK=true
. ./test-lib.sh
test_expect_success 'create tree with null sha1' '
diff --git a/t/t2107-update-index-basic.sh b/t/t2107-update-index-basic.sh
index cc72ead79f..f0eab13f96 100755
--- a/t/t2107-update-index-basic.sh
+++ b/t/t2107-update-index-basic.sh
@@ -5,6 +5,7 @@ test_description='basic update-index tests
Tests for command-line parsing and basic operation.
'
+TEST_PASSES_SANITIZE_LEAK=true
. ./test-lib.sh
test_expect_success 'update-index --nonsense fails' '
diff --git a/t/t7008-filter-branch-null-sha1.sh b/t/t7008-filter-branch-null-sha1.sh
index 93fbc92b8d..0ce8fd2c89 100755
--- a/t/t7008-filter-branch-null-sha1.sh
+++ b/t/t7008-filter-branch-null-sha1.sh
@@ -2,6 +2,7 @@
test_description='filter-branch removal of trees with null sha1'
+TEST_PASSES_SANITIZE_LEAK=true
. ./test-lib.sh
test_expect_success 'setup: base commits' '
Patrick Steinhardt
