From e8c42cb9ce6a566aad797cc6c5bc1279d608d819 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Thu, 6 Oct 2016 12:48:42 -0400 Subject: files_read_raw_ref: prevent infinite retry loops in general Limit the number of retries to 3. That should be adequate to prevent any races, while preventing the possibility of infinite loops if the logic fails to handle any other possible error modes correctly. After the fix in the previous commit, there's no known way to trigger an infinite loop, but I did manually verify that this fixes the test in that commit even when the code change is not applied. Signed-off-by: Jeff King Reviewed-by: Michael Haggerty Signed-off-by: Junio C Hamano --- refs/files-backend.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/refs/files-backend.c b/refs/files-backend.c index 087a8fa024..2455564352 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -1451,6 +1451,7 @@ int read_raw_ref(const char *refname, unsigned char *sha1, int fd; int ret = -1; int save_errno; + int remaining_retries = 3; *type = 0; strbuf_reset(&sb_path); @@ -1466,8 +1467,14 @@ stat_ref: * <-> symlink) between the lstat() and reading, then * we don't want to report that as an error but rather * try again starting with the lstat(). + * + * We'll keep a count of the retries, though, just to avoid + * any confusing situation sending us into an infinite loop. */ + if (remaining_retries-- <= 0) + goto out; + if (lstat(path, &st) < 0) { if (errno != ENOENT) goto out; -- cgit v1.2.1