linux/net/xdp
Magnus Karlsson 0fae7d269e xsk: Fix memory leak for failed bind
commit 8bee683384 upstream.

Fix a possible memory leak when a bind of an AF_XDP socket fails. When
the fill and completion rings are created, they are tied to the
socket. But when the buffer pool is later created at bind time, the
ownership of these two rings are transferred to the buffer pool as
they might be shared between sockets (and the buffer pool cannot be
created until we know what we are binding to). So, before the buffer
pool is created, these two rings are cleaned up with the socket, and
after they have been transferred they are cleaned up together with
the buffer pool.

The problem is that ownership was transferred before it was absolutely
certain that the buffer pool could be created and initialized
correctly and when one of these errors occurred, the fill and
completion rings did neither belong to the socket nor the pool and
where therefore leaked. Solve this by moving the ownership transfer
to the point where the buffer pool has been completely set up and
there is no way it can fail.

Fixes: 7361f9c3d7 ("xsk: Move fill and completion rings to buffer pool")
Reported-by: syzbot+cfa88ddd0655afa88763@syzkaller.appspotmail.com
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20201214085127.3960-1-magnus.karlsson@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-12 20:18:26 +01:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile xsk: Introduce AF_XDP buffer allocation API 2020-05-21 17:31:26 -07:00
xdp_umem.c xsk: Fix umem cleanup bug at socket destruct 2020-11-20 15:52:39 +01:00
xdp_umem.h xsk: Fix umem cleanup bug at socket destruct 2020-11-20 15:52:39 +01:00
xsk_buff_pool.c xsk: Fix memory leak for failed bind 2021-01-12 20:18:26 +01:00
xsk_diag.c xsk: Fix possible segfault in xsk umem diagnostics 2020-09-02 16:49:40 +02:00
xsk_queue.c xsk: Remove MEM_TYPE_ZERO_COPY and corresponding code 2020-05-21 17:31:27 -07:00
xsk_queue.h xsk: Change the tx writeable condition 2020-12-03 01:14:38 +01:00
xsk.c xsk: Fix memory leak for failed bind 2021-01-12 20:18:26 +01:00
xsk.h xsk: Fix possible segfault at xskmap entry insertion 2020-09-02 16:52:59 +02:00
xskmap.c bpf: Allow for map-in-map with dynamic inner array map entries 2020-10-11 10:21:04 -07:00