The user space application can directly trigger the allocations
from eventpoll_epi and eventpoll_pwq slabs. A buggy or malicious
application can consume a significant amount of system memory by
triggering such allocations. Indeed we have seen in production
where a buggy application was leaking the epoll references and
causing a burst of eventpoll_epi and eventpoll_pwq slab
allocations. This patch opt-in the charging of eventpoll_epi
and eventpoll_pwq slabs.
Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
---
fs/eventpoll.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 2fabd19cdeea..a45360444895 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2329,11 +2329,11 @@ static int __init eventpoll_init(void)
/* Allocates slab cache used to allocate "struct epitem" items */
epi_cache = kmem_cache_create("eventpoll_epi", sizeof(struct epitem),
- 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
+ 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL);
/* Allocates slab cache used to allocate "struct eppoll_entry" */
pwq_cache = kmem_cache_create("eventpoll_pwq",
- sizeof(struct eppoll_entry), 0, SLAB_PANIC, NULL);
+ sizeof(struct eppoll_entry), 0, SLAB_PANIC|SLAB_ACCOUNT, NULL);
return 0;
}
--
2.14.2.822.g60be5d43e6-goog
