1. 24 Aug, 2021 36 commits
  2. 23 Aug, 2021 1 commit
    • Jiang Wang's avatar
      af_unix: Fix NULL pointer bug in unix_shutdown · d359902d
      Jiang Wang authored
      Commit 94531cfc ("af_unix: Add unix_stream_proto for sockmap")
      introduced a bug for af_unix SEQPACKET type. In unix_shutdown, the
      unhash function will call prot->unhash(), which is NULL for SEQPACKET.
      And kernel will panic. On ARM32, it will show following messages: (it
      likely affects x86 too).
      
      Fix the bug by checking the prot->unhash is NULL or not first.
      
      Kernel log:
      <--- cut here ---
       Unable to handle kernel NULL pointer dereference at virtual address
      00000000
       pgd = 2fba1ffb
       *pgd=00000000
       Internal error: Oops: 80000005 [#1] PREEMPT SMP THUMB2
       Modules linked in:
       CPU: 1 PID: 1999 Comm: falkon Tainted: G        W
      5.14.0-rc5-01175-g94531cfc-dirty #9240
       Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
       PC is at 0x0
       LR is at unix_shutdown+0x81/0x1a8
       pc : [<00000000>]    lr : [<c08f3311>]    psr: 600f0013
       sp : e45aff70  ip : e463a3c0  fp : beb54f04
       r10: 00000125  r9 : e45ae000  r8 : c4a56664
       r7 : 00000001  r6 : c4a56464  r5 : 00000001  r4 : c4a56400
       r3 : 00000000  r2 : c5a6b180  r1 : 00000000  r0 : c4a56400
       Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
       Control: 50c5387d  Table: 05aa804a  DAC: 00000051
       Register r0 information: slab PING start c4a56400 pointer offset 0
       Register r1 information: NULL pointer
       Register r2 information: slab task_struct start c5a6b180 pointer offset 0
       Register r3 information: NULL pointer
       Register r4 information: slab PING start c4a56400 pointer offset 0
       Register r5 information: non-paged memory
       Register r6 information: slab PING start c4a56400 pointer offset 100
       Register r7 information: non-paged memory
       Register r8 information: slab PING start c4a56400 pointer offset 612
       Register r9 information: non-slab/vmalloc memory
       Register r10 information: non-paged memory
       Register r11 information: non-paged memory
       Register r12 information: slab filp start e463a3c0 pointer offset 0
       Process falkon (pid: 1999, stack limit = 0x9ec48895)
       Stack: (0xe45aff70 to 0xe45b0000)
       ff60:                                     e45ae000 c5f26a00 00000000 00000125
       ff80: c0100264 c07f7fa3 beb54f04 fffffff7 00000001 e6f3fc0e b5e5e9ec beb54ec4
       ffa0: b5da0ccc c010024b b5e5e9ec beb54ec4 0000000f 00000000 00000000 beb54ebc
       ffc0: b5e5e9ec beb54ec4 b5da0ccc 00000125 beb54f58 00785238 beb5529c beb54f04
       ffe0: b5da1e24 beb54eac b301385c b62b6ee8 600f0030 0000000f 00000000 00000000
       [<c08f3311>] (unix_shutdown) from [<c07f7fa3>] (__sys_shutdown+0x2f/0x50)
       [<c07f7fa3>] (__sys_shutdown) from [<c010024b>]
      (__sys_trace_return+0x1/0x16)
       Exception stack(0xe45affa8 to 0xe45afff0)
      
      Fixes: 94531cfc ("af_unix: Add unix_stream_proto for sockmap")
      Reported-by: default avatarDmitry Osipenko <digetx@gmail.com>
      Signed-off-by: default avatarJiang Wang <jiang.wang@bytedance.com>
      Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
      Tested-by: default avatarDmitry Osipenko <digetx@gmail.com>
      Acked-by: default avatarKuniyuki Iwashima <kuniyu@amazon.co.jp>
      Link: https://lore.kernel.org/bpf/20210821180738.1151155-1-jiang.wang@bytedance.com
      d359902d
  3. 19 Aug, 2021 3 commits