From d1bc8d484caa7b3157aa76da346badabf2a64d12 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Wed, 15 Aug 2018 00:37:05 +0200 Subject: [PATCH] lxccontainer: improve file locking Signed-off-by: Christian Brauner --- src/lxc/lxccontainer.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/src/lxc/lxccontainer.c b/src/lxc/lxccontainer.c index 04c2f672b..5f1e7330c 100644 --- a/src/lxc/lxccontainer.c +++ b/src/lxc/lxccontainer.c @@ -155,12 +155,13 @@ static int ongoing_create(struct lxc_container *c) if (ret < 0 || (size_t)ret >= len) return -1; - if (!file_exists(path)) - return 0; + fd = open(path, O_RDWR | O_CLOEXEC); + if (fd < 0) { + if (errno != ENOENT) + return -1; - fd = open(path, O_RDWR); - if (fd < 0) return 0; + } lk.l_type = F_WRLCK; lk.l_whence = SEEK_SET; @@ -170,8 +171,11 @@ static int ongoing_create(struct lxc_container *c) lk.l_pid = 0; ret = fcntl(fd, F_OFD_GETLK, &lk); - if (ret < 0 && errno == EINVAL) + if (ret < 0 && errno == EINVAL) { ret = flock(fd, LOCK_EX | LOCK_NB); + if (ret < 0 && errno == EWOULDBLOCK) + ret = 0; + } close(fd); @@ -198,7 +202,7 @@ static int create_partial(struct lxc_container *c) if (ret < 0 || (size_t)ret >= len) return -1; - fd = open(path, O_RDWR | O_CREAT | O_EXCL, 0755); + fd = open(path, O_RDWR | O_CREAT | O_EXCL | O_CLOEXEC, 0000); if (fd < 0) return -1; -- 2.39.2