threads / patch / 64763

patch[next] hook: check for NULL pointer before deref

Subject: [PATCH][next] hook: check for NULL pointer before deref

## tl;dr

3 messages between Jan 9, 2026 and Jan 9, 2026. Diffs are folded; open one to read it.

replies: 2people: 2as markdown or json

Adrian Ratiu· Jan 9, 2026, 15:35 UTC · lore

Fix a compiler warning (-Werror=analyzer-deref-before-check) due to dereferencing the options pointer before NULL checking it.

In practice run_hooks_opt() is never called with a NULL opt struct, so this just fixes the code to not trigger the warning anymore.

The NULL check is kept as-is because some future patches might end up calling run_hooks_opt with a NULL opt struct, which is clearly a bug.

While at it, also fix the BUG message function name.

Reported-by: correctmost <cmlists@sent.com>
Suggested-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
---
This is based on next, because it fixes a warning introduced in next.
Succesful CI run: https://github.com/10ne1/git/actions/runs/20855922803
---
 hook.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

Show changes to hook.c +4 −3

diff --git a/hook.c b/hook.c
index 35211e5ed7..c257bd3940 100644
--- a/hook.c
+++ b/hook.c
@@ -148,12 +148,11 @@ int run_hooks_opt(struct repository *r, const char *hook_name,
 	};
 	const char *const hook_path = find_hook(r, hook_name);
 	int ret = 0;
-	const struct run_process_parallel_opts opts = {
+	struct run_process_parallel_opts opts = {
 		.tr2_category = "hook",
 		.tr2_label = hook_name,
 
 		.processes = 1,
-		.ungroup = options->ungroup,
 
 		.get_next_task = pick_next_hook,
 		.start_failure = notify_start_failure,
@@ -165,11 +164,13 @@ int run_hooks_opt(struct repository *r, const char *hook_name,
 	};
 
 	if (!options)
-		BUG("a struct run_hooks_opt must be provided to run_hooks");
+		BUG("a struct run_hooks_opt must be provided to run_hooks_opt");
 
 	if (options->path_to_stdin && options->feed_pipe)
 		BUG("options path_to_stdin and feed_pipe are mutually exclusive");
 
+	opts.ungroup = options->ungroup;
+
 	if (options->invoked_hook)
 		*options->invoked_hook = 0;

-- 
2.51.2

Patrick Steinhardt· Jan 9, 2026, 15:51 UTC · re: Adrian Ratiu · lore

Re: [PATCH][next] hook: check for NULL pointer before deref

On Fri, Jan 09, 2026 at 05:35:28PM +0200, Adrian Ratiu wrote:

Show 18 quoted lines

> diff --git a/hook.c b/hook.c
> index 35211e5ed7..c257bd3940 100644
> --- a/hook.c
> +++ b/hook.c
> @@ -148,12 +148,11 @@ int run_hooks_opt(struct repository *r, const char *hook_name,
>  	};
>  	const char *const hook_path = find_hook(r, hook_name);
>  	int ret = 0;
> -	const struct run_process_parallel_opts opts = {
> +	struct run_process_parallel_opts opts = {
>  		.tr2_category = "hook",
>  		.tr2_label = hook_name,
>  
>  		.processes = 1,
> -		.ungroup = options->ungroup,
>  
>  		.get_next_task = pick_next_hook,
>  		.start_failure = notify_start_failure,

What's omitted here is that the next two lines also dereference `options`. That'll also have to be fixed for the warning to go away.

Patrick

Adrian Ratiu· Jan 9, 2026, 15:57 UTC · re: Patrick Steinhardt · lore

Re: [PATCH][next] hook: check for NULL pointer before deref

On Fri, 09 Jan 2026, Patrick Steinhardt <ps@pks.im> wrote:

Show 22 quoted lines

> On Fri, Jan 09, 2026 at 05:35:28PM +0200, Adrian Ratiu wrote:
>> diff --git a/hook.c b/hook.c
>> index 35211e5ed7..c257bd3940 100644
>> --- a/hook.c
>> +++ b/hook.c
>> @@ -148,12 +148,11 @@ int run_hooks_opt(struct repository *r, const char *hook_name,
>>  	};
>>  	const char *const hook_path = find_hook(r, hook_name);
>>  	int ret = 0;
>> -	const struct run_process_parallel_opts opts = {
>> +	struct run_process_parallel_opts opts = {
>>  		.tr2_category = "hook",
>>  		.tr2_label = hook_name,
>>  
>>  		.processes = 1,
>> -		.ungroup = options->ungroup,
>>  
>>  		.get_next_task = pick_next_hook,
>>  		.start_failure = notify_start_failure,
>
> What's omitted here is that the next two lines also dereference
> `options`. That'll also have to be fixed for the warning to go away.

Thanks for spotting this. Will fix in the same way.