e95de01edc
[ Upstream commit e57f61858b7cf478ed6fa23ed4b3876b1c9625c4 ] We take a pointer to grec prior to calling pskb_may_pull and use it afterwards to get nsrcs so record nsrcs before the pull when handling igmp3 and we get a pointer to nsrcs and call pskb_may_pull when handling mld2 which again could lead to reading 2 bytes out-of-bounds. ================================================================== BUG: KASAN: use-after-free in br_multicast_rcv+0x480c/0x4ad0 [bridge] Read of size 2 at addr ffff8880421302b4 by task ksoftirqd/1/16 CPU: 1 PID: 16 Comm: ksoftirqd/1 Tainted: G OE 5.2.0-rc6+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace: dump_stack+0x71/0xab print_address_description+0x6a/0x280 ? br_multicast_rcv+0x480c/0x4ad0 [bridge] __kasan_report+0x152/0x1aa ? br_multicast_rcv+0x480c/0x4ad0 [bridge] ? br_multicast_rcv+0x480c/0x4ad0 [bridge] kasan_report+0xe/0x20 br_multicast_rcv+0x480c/0x4ad0 [bridge] ? br_multicast_disable_port+0x150/0x150 [bridge] ? ktime_get_with_offset+0xb4/0x150 ? __kasan_kmalloc.constprop.6+0xa6/0xf0 ? __netif_receive_skb+0x1b0/0x1b0 ? br_fdb_update+0x10e/0x6e0 [bridge] ? br_handle_frame_finish+0x3c6/0x11d0 [bridge] br_handle_frame_finish+0x3c6/0x11d0 [bridge] ? br_pass_frame_up+0x3a0/0x3a0 [bridge] ? virtnet_probe+0x1c80/0x1c80 [virtio_net] br_handle_frame+0x731/0xd90 [bridge] ? select_idle_sibling+0x25/0x7d0 ? br_handle_frame_finish+0x11d0/0x11d0 [bridge] __netif_receive_skb_core+0xced/0x2d70 ? virtqueue_get_buf_ctx+0x230/0x1130 [virtio_ring] ? do_xdp_generic+0x20/0x20 ? virtqueue_napi_complete+0x39/0x70 [virtio_net] ? virtnet_poll+0x94d/0xc78 [virtio_net] ? receive_buf+0x5120/0x5120 [virtio_net] ? __netif_receive_skb_one_core+0x97/0x1d0 __netif_receive_skb_one_core+0x97/0x1d0 ? __netif_receive_skb_core+0x2d70/0x2d70 ? _raw_write_trylock+0x100/0x100 ? __queue_work+0x41e/0xbe0 process_backlog+0x19c/0x650 ? _raw_read_lock_irq+0x40/0x40 net_rx_action+0x71e/0xbc0 ? __switch_to_asm+0x40/0x70 ? napi_complete_done+0x360/0x360 ? __switch_to_asm+0x34/0x70 ? __switch_to_asm+0x40/0x70 ? __schedule+0x85e/0x14d0 __do_softirq+0x1db/0x5f9 ? takeover_tasklets+0x5f0/0x5f0 run_ksoftirqd+0x26/0x40 smpboot_thread_fn+0x443/0x680 ? sort_range+0x20/0x20 ? schedule+0x94/0x210 ? __kthread_parkme+0x78/0xf0 ? sort_range+0x20/0x20 kthread+0x2ae/0x3a0 ? kthread_create_worker_on_cpu+0xc0/0xc0 ret_from_fork+0x35/0x40 The buggy address belongs to the page: page:ffffea0001084c00 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 flags: 0xffffc000000000() raw: 00ffffc000000000 ffffea0000cfca08 ffffea0001098608 0000000000000000 raw: 0000000000000000 0000000000000003 00000000ffffff7f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888042130180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888042130200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff > ffff888042130280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888042130300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888042130380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== Disabling lock debugging due to kernel taint Fixes: bc8c20acaea1 ("bridge: multicast: treat igmpv3 report with INCLUDE and no sources as a leave") Reported-by: Martin Weinelt <martin@linuxlounge.net> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Tested-by: Martin Weinelt <martin@linuxlounge.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.