diff options
| author | Coly Li <colyli@suse.de> | 2020-10-02 16:27:31 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-10-02 15:27:08 -0700 |
| commit | cf83a17edeeb36195596d2dae060a7c381db35f1 (patch) | |
| tree | bd90a7efe648a0b8c2d75ca0a1dcaa4d6b89610d | |
| parent | 7d4194abfc4de13a2663c7fee6891de8360f7a52 (diff) | |
| download | linux-cf83a17edeeb36195596d2dae060a7c381db35f1.tar.gz | |
tcp: use sendpage_ok() to detect misused .sendpage
commit a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab
objects") adds the checks for Slab pages, but the pages don't have
page_count are still missing from the check.
Network layer's sendpage method is not designed to send page_count 0
pages neither, therefore both PageSlab() and page_count() should be
both checked for the sending page. This is exactly what sendpage_ok()
does.
This patch uses sendpage_ok() in do_tcp_sendpages() to detect misused
.sendpage, to make the code more robust.
Fixes: a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects")
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 31f3b858db8199..2135ee7c806da2 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -970,7 +970,8 @@ ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); if (IS_ENABLED(CONFIG_DEBUG_VM) && - WARN_ONCE(PageSlab(page), "page must not be a Slab one")) + WARN_ONCE(!sendpage_ok(page), + "page must not be a Slab one and have page_count > 0")) return -EINVAL; /* Wait for a connection to finish. One exception is TCP Fast Open |