The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From e886274031200bb60965c1b9c49b7acda56a93bd Mon Sep 17 00:00:00 2001

From: Ilya Dryomov idryomov@gmail.com Date: Tue, 10 Mar 2020 16:19:01 +0100 Subject: [PATCH] libceph: fix alloc_msg_with_page_vector() memory leaks

Make it so that CEPH_MSG_DATA_PAGES data item can own pages, fixing a bunch of memory leaks for a page vector allocated in alloc_msg_with_page_vector(). Currently, only watch-notify messages trigger this allocation, and normally the page vector is freed either in handle_watch_notify() or by the caller of ceph_osdc_notify(). But if the message is freed before that (e.g. if the session faults while reading in the message or if the notify is stale), we leak the page vector.

This was supposed to be fixed by switching to a message-owned pagelist, but that never happened.

Fixes: 1907920324f1 ("libceph: support for sending notifies") Reported-by: Roman Penyaev rpenyaev@suse.de Signed-off-by: Ilya Dryomov idryomov@gmail.com Reviewed-by: Roman Penyaev rpenyaev@suse.de

diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h index c4458dc6a757..76371aaae2d1 100644 --- a/include/linux/ceph/messenger.h +++ b/include/linux/ceph/messenger.h @@ -175,9 +175,10 @@ struct ceph_msg_data { #endif /* CONFIG_BLOCK */ struct ceph_bvec_iter bvec_pos; struct { - struct page **pages; /* NOT OWNER. */ + struct page **pages; size_t length; /* total # bytes */ unsigned int alignment; /* first page */ + bool own_pages; }; struct ceph_pagelist *pagelist; }; @@ -356,8 +357,8 @@ extern void ceph_con_keepalive(struct ceph_connection *con); extern bool ceph_con_keepalive_expired(struct ceph_connection *con, unsigned long interval);

-extern void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages, - size_t length, size_t alignment); +void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages, + size_t length, size_t alignment, bool own_pages); extern void ceph_msg_data_add_pagelist(struct ceph_msg *msg, struct ceph_pagelist *pagelist); #ifdef CONFIG_BLOCK diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 5b4bd8261002..f8ca5edc5f2c 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -3248,12 +3248,16 @@ static struct ceph_msg_data *ceph_msg_data_add(struct ceph_msg *msg)

static void ceph_msg_data_destroy(struct ceph_msg_data *data) { - if (data->type == CEPH_MSG_DATA_PAGELIST) + if (data->type == CEPH_MSG_DATA_PAGES && data->own_pages) { + int num_pages = calc_pages_for(data->alignment, data->length); + ceph_release_page_vector(data->pages, num_pages); + } else if (data->type == CEPH_MSG_DATA_PAGELIST) { ceph_pagelist_release(data->pagelist); + } }

void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages, - size_t length, size_t alignment) + size_t length, size_t alignment, bool own_pages) { struct ceph_msg_data *data;

@@ -3265,6 +3269,7 @@ void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages, data->pages = pages; data->length = length; data->alignment = alignment & ~PAGE_MASK; + data->own_pages = own_pages;

msg->data_length += length; } diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c index b68b376d8c2f..af868d3923b9 100644 --- a/net/ceph/osd_client.c +++ b/net/ceph/osd_client.c @@ -962,7 +962,7 @@ static void ceph_osdc_msg_data_add(struct ceph_msg *msg, BUG_ON(length > (u64) SIZE_MAX); if (length) ceph_msg_data_add_pages(msg, osd_data->pages, - length, osd_data->alignment); + length, osd_data->alignment, false); } else if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGELIST) { BUG_ON(!length); ceph_msg_data_add_pagelist(msg, osd_data->pagelist); @@ -4436,9 +4436,7 @@ static void handle_watch_notify(struct ceph_osd_client *osdc, CEPH_MSG_DATA_PAGES); *lreq->preply_pages = data->pages; *lreq->preply_len = data->length; - } else { - ceph_release_page_vector(data->pages, - calc_pages_for(0, data->length)); + data->own_pages = false; } } lreq->notify_finish_error = return_code; @@ -5506,9 +5504,6 @@ static struct ceph_msg *get_reply(struct ceph_connection *con, return m; }

-/* - * TODO: switch to a msg-owned pagelist - */ static struct ceph_msg *alloc_msg_with_page_vector(struct ceph_msg_header *hdr) { struct ceph_msg *m; @@ -5522,7 +5517,6 @@ static struct ceph_msg *alloc_msg_with_page_vector(struct ceph_msg_header *hdr)

if (data_len) { struct page **pages; - struct ceph_osd_data osd_data;

pages = ceph_alloc_page_vector(calc_pages_for(0, data_len), GFP_NOIO); @@ -5531,9 +5525,7 @@ static struct ceph_msg *alloc_msg_with_page_vector(struct ceph_msg_header *hdr) return NULL; }

- ceph_osd_data_pages_init(&osd_data, pages, data_len, 0, false, - false); - ceph_osdc_msg_data_add(m, &osd_data); + ceph_msg_data_add_pages(m, pages, data_len, 0, true); }

return m;