From: Vasily Averin vvs@virtuozzo.com
[ Upstream commit 0e18dd12064e07519f7cbff4149ca7fff620cbed ]
perf with --namespace key leaks various memory objects including namespaces
4.14.0+ pid_namespace 1 12 2568 12 8 user_namespace 1 39 824 39 8 net_namespace 1 5 6272 5 8
This happen because perf_fill_ns_link_info() struct patch ns_path: during initialization ns_path incremented counters on related mnt and dentry, but without lost path_put nobody decremented them back. Leaked dentry is name of related namespace, and its leak does not allow to free unused namespace.
Signed-off-by: Vasily Averin vvs@virtuozzo.com Acked-by: Peter Zijlstra peterz@infradead.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Arnaldo Carvalho de Melo acme@kernel.org Cc: Hari Bathini hbathini@linux.vnet.ibm.com Cc: Jiri Olsa jolsa@redhat.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Namhyung Kim namhyung@kernel.org Cc: Thomas Gleixner tglx@linutronix.de Fixes: commit e422267322cd ("perf: Add PERF_RECORD_NAMESPACES to include namespaces related info") Link: http://lkml.kernel.org/r/c510711b-3904-e5e1-d296-61273d21118d@virtuozzo.com Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- kernel/events/core.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/kernel/events/core.c b/kernel/events/core.c index 24ebad5567b4..8c20af8738ac 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6756,6 +6756,7 @@ static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, ns_inode = ns_path.dentry->d_inode; ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); ns_link_info->ino = ns_inode->i_ino; + path_put(&ns_path); } }