package/kernel/mac80211/patches/373-brcmfmac-avoid-null-pointer-access-when-brcmf_msgbuf.patch

   1 From: Arend van Spriel <arend@broadcom.com>
   2 Date: Tue, 26 May 2015 13:19:46 +0200
   3 Subject: [PATCH] brcmfmac: avoid null pointer access when
   4  brcmf_msgbuf_get_pktid() fails
   5
   6 The function brcmf_msgbuf_get_pktid() may return a NULL pointer so
   7 the callers should check the return pointer before accessing it to
   8 avoid the crash below (see [1]):
   9
  10 brcmfmac: brcmf_msgbuf_get_pktid: Invalid packet id 273 (not in use)
  11 BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
  12 IP: [<ffffffff8145b225>] skb_pull+0x5/0x50
  13 PGD 0
  14 Oops: 0000 [#1] PREEMPT SMP
  15 Modules linked in: pci_stub vboxpci(O) vboxnetflt(O) vboxnetadp(O) vboxdrv(O)
  16  snd_hda_codec_hdmi bnep mousedev hid_generic ushwmon msr ext4 crc16 mbcache
  17  jbd2 sd_mod uas usb_storage ahci libahci libata scsi_mod xhci_pci xhci_hcd
  18  usbcore usb_common
  19 CPU: 0 PID: 1661 Comm: irq/61-brcmf_pc Tainted: G O    4.0.1-MacbookPro-ARCH #1
  20 Hardware name: Apple Inc. MacBookPro12,1/Mac-E43C1C25D4880AD6,
  21  BIOS MBP121.88Z.0167.B02.1503241251 03/24/2015
  22 task: ffff880264203cc0 ti: ffff88025ffe4000 task.ti: ffff88025ffe4000
  23 RIP: 0010:[<ffffffff8145b225>]  [<ffffffff8145b225>] skb_pull+0x5/0x50
  24 RSP: 0018:ffff88025ffe7d40  EFLAGS: 00010202
  25 RAX: 0000000000000000 RBX: ffff88008a33c000 RCX: 0000000000000044
  26 RDX: 0000000000000000 RSI: 000000000000004a RDI: 0000000000000000
  27 RBP: ffff88025ffe7da8 R08: 0000000000000096 R09: 000000000000004a
  28 R10: 0000000000000000 R11: 000000000000048e R12: ffff88025ff14f00
  29 R13: 0000000000000000 R14: ffff880263b48200 R15: ffff88008a33c000
  30 FS:  0000000000000000(0000) GS:ffff88026ec00000(0000) knlGS:0000000000000000
  31 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  32 CR2: 0000000000000080 CR3: 000000000180b000 CR4: 00000000003407f0
  33 Stack:
  34  ffffffffa06aed74 ffff88025ffe7dc8 ffff880263b48270 ffff880263b48278
  35  05ea88020000004a 0002ffff81014635 000000001720b2f6 ffff88026ec116c0
  36  ffff880263b48200 0000000000010000 ffff880263b4ae00 ffff880264203cc0
  37 Call Trace:
  38  [<ffffffffa06aed74>] ? brcmf_msgbuf_process_rx+0x404/0x480 [brcmfmac]
  39  [<ffffffff810cea60>] ? irq_finalize_oneshot.part.30+0xf0/0xf0
  40  [<ffffffffa06afb55>] brcmf_proto_msgbuf_rx_trigger+0x35/0xf0 [brcmfmac]
  41  [<ffffffffa06baf2a>] brcmf_pcie_isr_thread_v2+0x8a/0x130 [brcmfmac]
  42  [<ffffffff810cea80>] irq_thread_fn+0x20/0x50
  43  [<ffffffff810ceddf>] irq_thread+0x13f/0x170
  44  [<ffffffff810cebf0>] ? wake_threads_waitq+0x30/0x30
  45  [<ffffffff810ceca0>] ? irq_thread_dtor+0xb0/0xb0
  46  [<ffffffff81092a08>] kthread+0xd8/0xf0
  47  [<ffffffff81092930>] ? kthread_create_on_node+0x1c0/0x1c0
  48  [<ffffffff8156d898>] ret_from_fork+0x58/0x90
  49  [<ffffffff81092930>] ? kthread_create_on_node+0x1c0/0x1c0
  50 Code: 01 83 e2 f7 88 50 01 48 83 c4 08 5b 5d f3 c3 0f 1f 80 00 00 00 00 83 e2
  51  f7 88 50 01 c3 66 0f 1f 84 00 00 00 00 00 0f 1f
  52 RIP  [<ffffffff8145b225>] skb_pull+0x5/0x50
  53  RSP <ffff88025ffe7d40>
  54 CR2: 0000000000000080
  55 ---[ end trace b074c0f90e7c997d ]---
  56
  57 [1] http://mid.gmane.org/20150430193259.GA5630@googlemail.com
  58
  59 Cc: <stable@vger.kernel.org> # v3.18, v3.19, v4.0, v4.1
  60 Reported-by: Michael Hornung <mhornung.linux@gmail.com>
  61 Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
  62 Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
  63 Signed-off-by: Arend van Spriel <arend@broadcom.com>
  64 ---
  65
  66 --- a/drivers/net/wireless/brcm80211/brcmfmac/msgbuf.c
  67 +++ b/drivers/net/wireless/brcm80211/brcmfmac/msgbuf.c
  68 @@ -500,11 +500,9 @@ static int brcmf_msgbuf_query_dcmd(struc
  69                                      msgbuf->rx_pktids,
  70                                      msgbuf->ioctl_resp_pktid);
  71         if (msgbuf->ioctl_resp_ret_len != 0) {
  72 -               if (!skb) {
  73 -                       brcmf_err("Invalid packet id idx recv'd %d\n",
  74 -                                 msgbuf->ioctl_resp_pktid);
  75 +               if (!skb)
  76                         return -EBADF;
  77 -               }
  78 +
  79                 memcpy(buf, skb->data, (len < msgbuf->ioctl_resp_ret_len) ?
  80                                        len : msgbuf->ioctl_resp_ret_len);
  81         }
  82 @@ -866,10 +864,8 @@ brcmf_msgbuf_process_txstatus(struct brc
  83         flowid -= BRCMF_NROF_H2D_COMMON_MSGRINGS;
  84         skb = brcmf_msgbuf_get_pktid(msgbuf->drvr->bus_if->dev,
  85                                      msgbuf->tx_pktids, idx);
  86 -       if (!skb) {
  87 -               brcmf_err("Invalid packet id idx recv'd %d\n", idx);
  88 +       if (!skb)
  89                 return;
  90 -       }
  91
  92         set_bit(flowid, msgbuf->txstatus_done_map);
  93         commonring = msgbuf->flowrings[flowid];
  94 @@ -1148,6 +1144,8 @@ brcmf_msgbuf_process_rx_complete(struct
  95
  96         skb = brcmf_msgbuf_get_pktid(msgbuf->drvr->bus_if->dev,
  97                                      msgbuf->rx_pktids, idx);
  98 +       if (!skb)
  99 +               return;
 100
 101         if (data_offset)
 102                 skb_pull(skb, data_offset);