[PATCH 07/26] pidns: Improve the error handling in alloc_pid
From: Eric W. Biederman <hidden>
Date: 2017-06-06 19:12:17
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
Cause any failure to allocate pid 1 to permanently disable pid allocations for the pid namespace. Before the pid becomes pid 1 there ns->last_pid and other state remains unchanged so it is safe to try again... Signed-off-by: "Eric W. Biederman" <redacted> --- kernel/pid.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/kernel/pid.c b/kernel/pid.c
index fd1cde1e4576..f4fb1a84109b 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c@@ -321,10 +321,8 @@ struct pid *alloc_pid(struct pid_namespace *ns) } if (unlikely(is_child_reaper(pid))) { - if (pid_ns_prepare_proc(ns)) { - disable_pid_allocation(ns); + if (pid_ns_prepare_proc(ns)) goto out_free; - } } get_pid_ns(ns);
@@ -350,6 +348,10 @@ struct pid *alloc_pid(struct pid_namespace *ns) put_pid_ns(ns); out_free: + /* Ensure everything stops if allocation of pid 1 failed */ + if ((i < ns->level) && (pid->numbers[ns->level].nr == 1)) + disable_pid_allocation(ns); + while (++i <= ns->level) free_pidmap(pid->numbers + i);
--
2.10.1