coverity: fix leaks and error paths#2163
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Pointed out by Coverity. While at it, reduce near-duplicate clean-up code at the end of the function. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
`write_one_object()` opens a file at line 186 and jumps to the errout label on failure. The errout cleanup unconditionally calls `close(fd)`, but when `open()` itself failed, fd is -1. Calling `close(-1)` is harmless on most platforms (returns EBADF) but is undefined behavior per POSIX and can confuse fd tracking in sanitizer builds. Guard the close with fd >= 0. Pointed out by Coverity. Assisted-by: Claude Opus 4.6 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When the `git-remote-https` command fails, we do not want to leak `child_out`. Pointed out by Coverity. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When `start_command()` fails to set up a pipe partway through, it rolls
back by closing the pipe ends it has already opened. For descriptors
supplied by the caller rather than allocated locally, that rollback
tested `if (cmd->in)` / `if (cmd->out)` before calling close(). The
CHILD_PROCESS_INIT default of -1 ("no descriptor") is non-zero and so
passes the test, meaning a caller that sets cmd->no_stdin or
cmd->no_stdout without supplying a real fd ends up triggering close(-1)
on the error path.
The stdin-pipe failure branch a few lines above already uses the right
idiom, `if (cmd->out > 0)`, which rejects both the -1 sentinel and 0
(the parent's own standard streams). Apply it to the three remaining
rollback sites.
Reported by Coverity as CID 1049722 ("Argument cannot be negative").
Assisted-by: Opus 4.7
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When `bloom_filter_check()` indicates that a commit does not touch any of the tracked paths, `line_log_process_ranges_arbitrary_commit()` propagates the current ranges to the parent by calling `line_log_data_copy()` and passing the copy to add_line_range(). However, `add_line_range()` always makes its own copy internally (via line_log_data_copy or line_log_data_merge), so the caller's copy is never freed and leaks every time this path is taken. Pass range directly to `add_line_range()` instead of making a redundant intermediate copy. The callee's internal copy handles ownership correctly. Pointed out by Coverity. Assisted-by: Claude Opus 4.6 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Two of `read_one_dir()`'s parse-error early returns leak ud.untracked and ud.dirs. Plug them. The other early returns in the same function are fine: they occur after the `xmalloc()`+`memcpy()` that copies ud into `*untracked_`, at which point ownership is transferred to the caller. `read_untracked_extension()` then releases everything via `free_untracked_cache()` on failure. Pointed out by Coverity. Assisted-by: Claude Opus 4.6 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
`get_superproject_working_tree()` allocates cwd via `xgetcwd()` at the top of the function, but two early-return paths (when not inside a work tree, and when strbuf_realpath for "../" fails) return 0 without freeing it. Redirect these early returns through a cleanup label that frees cwd before returning. Pointed out by Coverity. Assisted-by: Claude Opus 4.6 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In the "add" subcommand, when `run_command()` fails while creating a new branch (line 948), the function returns -1 immediately without freeing the allocations made earlier: path (from prefix_filename at line 858), opt_track, branch_to_free, and new_branch_to_free. Redirect the error return through the existing cleanup block at the end of the function so all four allocations are properly freed. Pointed out by Coverity. Assisted-by: Claude Opus 4.6 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When uploading messages via libcurl, `curl_append_msgs_to_imap()` accumulates each one in a strbuf that grows across loop iterations but is never released before the function returns. Release it alongside the existing libcurl cleanup. Reported by Coverity as CID 1671507 ("Resource leak"). Assisted-by: Opus 4.7 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
`reftable_table_refs_for_unindexed()` allocates a filtering_ref_iterator and then calls `reftable_buf_add()` to populate its oid buffer. On success ownership is transferred to the output iterator, but if `reftable_buf_add()` fails, the goto-out cleanup only frees the table iterator and walks away from both the filter allocation and the oid buffer that `reftable_buf_add()` may have grown. Release filter->oid and free filter alongside the existing table iterator cleanup. Reported by Coverity as CID 1671512 ("Resource leak"). Assisted-by: Opus 4.7 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
`fsmonitor_run_daemon()` allocates `state.current_token_data` before any subordinate setup step that may fail (alias resolution, listener/health constructors, asynchronous IPC server init). On the successful path the listener thread takes ownership and clears the field during its teardown, so the `done:` cleanup block sees a NULL pointer. On every early-error path, however, control jumps straight to `done:` with the freshly allocated token data still referenced, and it is never freed, as Coverity flagged. Free it at the top of `done:` and clear the pointer. The success path is a no-op (the pointer is already NULL there); the error paths now drop the otherwise-leaked allocation. `fsmonitor_free_token_data()` is NULL-safe and asserts `client_ref_count == 0`, which holds trivially here because the IPC server has not yet begun accepting clients when these failures occur. Assisted-by: Opus 4.7 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
After "mingw: kill child processes in a gentler way", the ownership of the HANDLE passed to `exit_process()` and `terminate_process_tree()` is inconsistent. `terminate_process_tree()` always closes the handle; `exit_process()` closes it on success and on the terminate-tree fallback, but leaks it on the early return where GetExitCodeProcess() fails or reports the process is no longer STILL_ACTIVE. `mingw_kill()` compensated by closing the handle on its own error path, which is a double-close on every error path that does not hit that one leaky branch -- the callee has already closed the handle by then. Coverity flagged the resulting use-after-free as CID 1437238. Pin down the invariant that `exit_process()` and `terminate_process_tree()` own the handle from the call onward and close it on every return path; with that, the bogus close in `mingw_kill()` goes away. Assisted-by: Opus 4.7 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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I wanted to whittle down the many issues reported by Coverity in the Git for Windows project. Turns out: The vast majority of the issues are false positives. Most of the remaining issues are in core Git proper.
This effort was forced on pause while Coverity was down from May 16 to June 22).
Here is a first batch of fixes for those issues.
Changes since v1:
errnoto determine the return value ofload_one_loose_object_map().read_one_dir()" to clarify ownership of the allocateduntracked/dirsbuffers.get_superproject_working_tree()" to reduce the cognitive load on the reader (i.e. to make it a lot easier to reason about the correctness of the patch).