From 3d7747e318532a36a263c61cdf92f2decb6424ff Mon Sep 17 00:00:00 2001 From: Alexandr Miloslavskiy Date: Tue, 10 Mar 2020 13:11:22 +0000 Subject: real_path: remove unsafe API Returning a shared buffer invites very subtle bugs due to reentrancy or multi-threading, as demonstrated by the previous patch. There was an unfinished effort to abolish this [1]. Let's finally rid of `real_path()`, using `strbuf_realpath()` instead. This patch uses a local `strbuf` for most places where `real_path()` was previously called. However, two places return the value of `real_path()` to the caller. For them, a `static` local `strbuf` was added, effectively pushing the problem one level higher: read_gitfile_gently() get_superproject_working_tree() [1] https://lore.kernel.org/git/1480964316-99305-1-git-send-email-bmwill@google.com/ Signed-off-by: Alexandr Miloslavskiy Signed-off-by: Junio C Hamano --- worktree.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'worktree.c') diff --git a/worktree.c b/worktree.c index eba4fd3a03..e7bbf716f6 100644 --- a/worktree.c +++ b/worktree.c @@ -285,6 +285,7 @@ int validate_worktree(const struct worktree *wt, struct strbuf *errmsg, unsigned flags) { struct strbuf wt_path = STRBUF_INIT; + struct strbuf realpath = STRBUF_INIT; char *path = NULL; int err, ret = -1; @@ -336,7 +337,8 @@ int validate_worktree(const struct worktree *wt, struct strbuf *errmsg, goto done; } - ret = fspathcmp(path, real_path(git_common_path("worktrees/%s", wt->id))); + strbuf_realpath(&realpath, git_common_path("worktrees/%s", wt->id), 1); + ret = fspathcmp(path, realpath.buf); if (ret) strbuf_addf_gently(errmsg, _("'%s' does not point back to '%s'"), @@ -344,6 +346,7 @@ int validate_worktree(const struct worktree *wt, struct strbuf *errmsg, done: free(path); strbuf_release(&wt_path); + strbuf_release(&realpath); return ret; } -- cgit v1.2.3