From b0ed17be63fa9f1af6b5367b65b398d3331845da Mon Sep 17 00:00:00 2001
From: Filipe Cabecinhas <me@filcab.net>
Date: Thu, 29 Oct 2015 23:37:28 +0000
Subject: [PATCH] Don't assert if materializing before seeing any function
 bodies

This assert was reachable from user input. A minimized test case (no
FUNCTION_BLOCK_ID record) is attached.

Bug found with afl-fuzz

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251667 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Bitcode/Reader/BitcodeReader.cpp             |   4 +++-
 test/Bitcode/Inputs/invalid-no-function-block.bc | Bin 0 -> 548 bytes
 test/Bitcode/invalid.test                        |   5 +++++
 3 files changed, 8 insertions(+), 1 deletion(-)
 create mode 100644 test/Bitcode/Inputs/invalid-no-function-block.bc

diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index e23f8176330..d2cbe9e85a4 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3054,7 +3054,9 @@ std::error_code BitcodeReader::rememberAndSkipFunctionBodies() {
 
   if (Stream.AtEndOfStream()) return error("Could not find function in stream");
 
-  assert(SeenFirstFunctionBody);
+  if (!SeenFirstFunctionBody)
+    return error("Trying to materialize functions before seeing function blocks");
+
   // An old bitcode file with the symbol table at the end would have
   // finished the parse greedily.
   assert(SeenValueSymbolTable);
diff --git a/test/Bitcode/Inputs/invalid-no-function-block.bc b/test/Bitcode/Inputs/invalid-no-function-block.bc
new file mode 100644
index 0000000000000000000000000000000000000000..52b65588e4a72ef92a824a67dc8d4d5c1f07e1ec
GIT binary patch
literal 548
zcmZ>AK5)-egn@yTfq@~3$3Vp=a^JJJpY3uLE(<ULg%}ih7#Qk-G<TB%14uv^h}j#J
zCpw;B@njP)vYf=&!lTN{At}ewoz%eN%H%YO+bKoBNW_9e!kf#;sKaA|h=Q|Q$5IAK
zBc~@Gd=n-r9tm&^Z0vd1{IrWj(v7WC0cbYROe3We911C|ERz+Nv;c|6Eej`z2>G=2
zaJQuR2#6>%6tg4*u(X&60F^R0%Q1o|2>4{c5C&u!b2P{tc_@=6!f4y!Y|(PK$Ekt6
zvVy&MMj_8L2L87Kd|w*)jCq{o4jq&|w@@a{fEBE)S^5mK?Fnbw9%kD!6+I;d?A09X
zl^*Q{1?*J?%w-kr1q$twX9W4)OyGNHz@KNp|M&ynhX6iffg`f_6lHEG${tFTOEc)S
z-qUP-!P#;Pv(27nn-*s4Gap3C64<LV*v&KAi-2T9d%=YEf&}(54fe7htUzPS8`|SJ
z+6yJxi)OS}&S=zm_kr)-1HP{Z_}&;WC!JU*^JJmS88CS#QRbAQ%#lXfQ;BTXCOBK3
zaJHNQCU+dRnBr{F!E8O{us+bzKTXzGn5{P)<~g3(UJ%h<RM1?K!CsNjULw(6vY=h^
zTrmGT2L4Y0d`~9uJ$B%KsKECI=nDl6**gd24mrwQQk1#VD0k<9%#(+*uNdXhBmylq
MI9ttWwuS~V01kw>r~m)}

literal 0
HcmV?d00001

diff --git a/test/Bitcode/invalid.test b/test/Bitcode/invalid.test
index 69104046df2..24ccd8bccd5 100644
--- a/test/Bitcode/invalid.test
+++ b/test/Bitcode/invalid.test
@@ -207,3 +207,8 @@ RUN: not llvm-dis -disable-output %p/Inputs/invalid-alias-type-mismatch.bc 2>&1
 RUN:   FileCheck --check-prefix=ALIAS-TYPE-MISMATCH %s
 
 ALIAS-TYPE-MISMATCH: Alias and aliasee types don't match
+
+RUN: not llvm-dis -disable-output %p/Inputs/invalid-no-function-block.bc 2>&1 | \
+RUN:   FileCheck --check-prefix=NO-FUNCTION-BLOCK %s
+
+NO-FUNCTION-BLOCK: Trying to materialize functions before seeing function blocks
-- 
2.34.1