zfs-patches/0026-Fix-zdb-E-segfault.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Chunwei Chen <david.chen@nutanix.com>
   3 Date: Thu, 1 Feb 2018 16:28:11 -0800
   4 Subject: [PATCH] Fix zdb -E segfault
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 SPA_MAXBLOCKSIZE is too large for stack.
  10
  11 Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
  12 Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
  13 Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
  14 Closes #7099
  15 (cherry picked from commit 31ff122aa2e20c7ed48617868085ddba7b4ad174)
  16 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  17 ---
  18  cmd/zdb/zdb.c | 6 ++++--
  19  1 file changed, 4 insertions(+), 2 deletions(-)
  20
  21 diff --git a/cmd/zdb/zdb.c b/cmd/zdb/zdb.c
  22 index 2d80589ca..90847d8d9 100644
  23 --- a/cmd/zdb/zdb.c
  24 +++ b/cmd/zdb/zdb.c
  25 @@ -4139,11 +4139,12 @@ zdb_embedded_block(char *thing)
  26  {
  27         blkptr_t bp;
  28         unsigned long long *words = (void *)&bp;
  29 -       char buf[SPA_MAXBLOCKSIZE];
  30 +       char *buf;
  31         int err;
  32
  33 -       memset(&bp, 0, sizeof (blkptr_t));
  34 +       buf = umem_alloc(SPA_MAXBLOCKSIZE, UMEM_NOFAIL);
  35
  36 +       bzero(&bp, sizeof (bp));
  37         err = sscanf(thing, "%llx:%llx:%llx:%llx:%llx:%llx:%llx:%llx:"
  38             "%llx:%llx:%llx:%llx:%llx:%llx:%llx:%llx",
  39             words + 0, words + 1, words + 2, words + 3,
  40 @@ -4161,6 +4162,7 @@ zdb_embedded_block(char *thing)
  41                 exit(1);
  42         }
  43         zdb_dump_block_raw(buf, BPE_GET_LSIZE(&bp), 0);
  44 +       umem_free(buf, SPA_MAXBLOCKSIZE);
  45  }
  46
  47  int
  48 --
  49 2.14.2
  50