From 3af1cae469555485cd3ef003aa2a55bd2a4f544f Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Mon, 8 Jun 2009 23:26:44 -0700 Subject: [PATCH] show-branch: fix segfault when showbranch.default exists When running "git show-branch" without any parameter in a repository that has showbranch.default defined, we used to rely on the fact that our handcrafted option parsing loop never looked at av[0]. The array of default strings had the first real command line argument in default_arg[0], but the option parser wanted to look at the array starting at av[1], so we assigned the address of -1th element to av to force the loop start working from default_arg[0]. This no longer worked since 5734365 (show-branch: migrate to parse-options API, 2009-05-21), as parse_options_start() saved the incoming &av[0] in its ctx->out and later in parse_options_end() it did memmove to ctx->out (with ctx->cpidx == 0), overwriting the memory before default_arg[] array. I am not sure if this is a bug in parse_options(), or a bug in the caller, and tonight I do not have enough concentration to figure out which. In any case, this patch works the issue around. Signed-off-by: Junio C Hamano --- builtin-show-branch.c | 14 +++++++++++--- t/t3202-show-branch-octopus.sh | 8 ++++++++ 2 files changed, 19 insertions(+), 3 deletions(-) diff --git a/builtin-show-branch.c b/builtin-show-branch.c index b1affd2ff..5d85ab0ca 100644 --- a/builtin-show-branch.c +++ b/builtin-show-branch.c @@ -565,7 +565,15 @@ static int git_show_branch_config(const char *var, const char *value, void *cb) if (!strcmp(var, "showbranch.default")) { if (!value) return config_error_nonbool(var); - if (default_alloc <= default_num + 1) { + /* + * default_arg is now passed to parse_options(), so we need to + * mimick the real argv a bit better. + */ + if (!default_num) { + default_alloc = 20; + default_arg = xcalloc(default_alloc, sizeof(*default_arg)); + default_arg[default_num++] = "show-branch"; + } else if (default_alloc <= default_num + 1) { default_alloc = default_alloc * 3 / 2 + 20; default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc); } @@ -693,8 +701,8 @@ int cmd_show_branch(int ac, const char **av, const char *prefix) /* If nothing is specified, try the default first */ if (ac == 1 && default_num) { - ac = default_num + 1; - av = default_arg - 1; /* ick; we would not address av[0] */ + ac = default_num; + av = default_arg; } ac = parse_options(ac, av, builtin_show_branch_options, diff --git a/t/t3202-show-branch-octopus.sh b/t/t3202-show-branch-octopus.sh index 7fe4a6ecb..0a5d5e669 100755 --- a/t/t3202-show-branch-octopus.sh +++ b/t/t3202-show-branch-octopus.sh @@ -56,4 +56,12 @@ test_expect_success 'show-branch with more than 8 branches' ' ' +test_expect_success 'show-branch with showbranch.default' ' + for i in $numbers; do + git config --add showbranch.default branch$i + done && + git show-branch >out && + test_cmp expect out +' + test_done -- 2.30.2