From 5e3bd0e684a3c32bd22647938247ac3699c5372a Mon Sep 17 00:00:00 2001
From: Chunwei Chen <david.chen@nutanix.com>
Date: Thu, 1 Feb 2018 16:28:11 -0800
Subject: [PATCH] Fix zdb -E segfault

SPA_MAXBLOCKSIZE is too large for stack.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes #7099
---
 cmd/zdb/zdb.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/cmd/zdb/zdb.c b/cmd/zdb/zdb.c
index 4c0a8245f..7f2cab382 100644
--- a/cmd/zdb/zdb.c
+++ b/cmd/zdb/zdb.c
@@ -4235,9 +4235,11 @@ zdb_embedded_block(char *thing)
 {
 	blkptr_t bp;
 	unsigned long long *words = (void *)&bp;
-	char buf[SPA_MAXBLOCKSIZE];
+	char *buf;
 	int err;
 
+	buf = umem_alloc(SPA_MAXBLOCKSIZE, UMEM_NOFAIL);
+
 	bzero(&bp, sizeof (bp));
 	err = sscanf(thing, "%llx:%llx:%llx:%llx:%llx:%llx:%llx:%llx:"
 	    "%llx:%llx:%llx:%llx:%llx:%llx:%llx:%llx",
@@ -4256,6 +4258,7 @@ zdb_embedded_block(char *thing)
 		exit(1);
 	}
 	zdb_dump_block_raw(buf, BPE_GET_LSIZE(&bp), 0);
+	umem_free(buf, SPA_MAXBLOCKSIZE);
 }
 
 int
-- 
2.40.0