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[geremy condra <debatem1 AT gmail.com>]

Hey all, me again.

After getting safecode to compile cleanly against 3.0 (thanks for all
the help there!) I started running through some of the test cases to
help me understand what the limitations of the technology were. While
I'm still not 100% sure I'm doing everything right, it looks like a
lot of the tests in the safecode/test/mem_safety/double_free directory
are failing. Can you help me understand why, for instance
double_free-001.c still runs without generating safecode warnings? Or
why double_free-031.c aborts with a glibc double free error? I assume
I've misconfigured something.

Here's how I'm building:


#! /bin/sh

set -e

# We do all of this in /tmp to make sure we're building locally
cd /tmp

# Get mainline llvm
echo "Getting llvm..."
svn co http://llvm.org/svn/llvm-project/llvm/tags/RELEASE_30 llvm

# Get all the projects we need
echo "Getting safecode projects..."
cd llvm/rc1/projects
svn co http://llvm.org/svn/llvm-project/poolalloc/trunk poolalloc
svn co http://llvm.org/svn/llvm-project/safecode/trunk safecode
svn co http://llvm.org/svn/llvm-project/cfe/trunk clang

# Configure everything
echo "Configuring..."
cd ..
./configure

# Make everything
echo "Making..."
make -j16 tools-only > /tmp/make_tools.out
cd projects/poolalloc
make -j16 > /tmp/make_poolalloc.out
cd ../safecode
make -j16 > /tmp/make_safecode.out
cd ..

# Install
echo "Installing..."
cd ..
sudo make install > /tmp/install_all.out
cd projects/poolalloc
sudo make install > /tmp/install_poolalloc.out
cd ../safecode
sudo make install > /tmp/install_safecode.out

# Go home
echo "Done."



Here's how I'm compiling and running the test:

clang -g -fmemsafety -o test double_free-031.c -L/usr/local/lib
-lsc_dbg_rt -lpoolalloc_bitmap -lstdc++ -lgdtoa
./test



And here's the output:

user@machine:/tmp/llvm/rc1/projects/safecode/test/mem_safety/double_free$
 ./test
0x402910
0x402910
*** glibc detected *** ./test: double free or corruption (!prev):
0x000000000161d830 ***
======= Backtrace: =========
/lib/libc.so.6(+0x775b6)[0x7f69286fb5b6]
/lib/libc.so.6(cfree+0x73)[0x7f6928701e83]
./test[0x40334c]
./test[0x403631]
/lib/libc.so.6(__libc_start_main+0xfd)[0x7f69286a2c4d]
./test[0x402bb9]
======= Memory map: ========
00400000-00435000 r-xp 00000000 fc:00 1847636
  /tmp/llvm/rc1/projects/safecode/test/mem_safety/double_free/test
00634000-00635000 r--p 00034000 fc:00 1847636
  /tmp/llvm/rc1/projects/safecode/test/mem_safety/double_free/test
00635000-00636000 rw-p 00035000 fc:00 1847636
  /tmp/llvm/rc1/projects/safecode/test/mem_safety/double_free/test
0161d000-0163e000 rw-p 00000000 00:00 0                                  
[heap]
7f6924000000-7f6924021000 rw-p 00000000 00:00 0
7f6924021000-7f6928000000 ---p 00000000 00:00 0
7f69281ea000-7f6928200000 r-xp 00000000 fc:00 393235
  /lib/libgcc_s.so.1
7f6928200000-7f69283ff000 ---p 00016000 fc:00 393235
  /lib/libgcc_s.so.1
7f69283ff000-7f6928400000 r--p 00015000 fc:00 393235
  /lib/libgcc_s.so.1
7f6928400000-7f6928401000 rw-p 00016000 fc:00 393235
  /lib/libgcc_s.so.1
7f6928401000-7f6928483000 r-xp 00000000 fc:00 394146
  /lib/libm-2.11.1.so
7f6928483000-7f6928682000 ---p 00082000 fc:00 394146
  /lib/libm-2.11.1.so
7f6928682000-7f6928683000 r--p 00081000 fc:00 394146
  /lib/libm-2.11.1.so
7f6928683000-7f6928684000 rw-p 00082000 fc:00 394146
  /lib/libm-2.11.1.so
7f6928684000-7f69287fe000 r-xp 00000000 fc:00 393815
  /lib/libc-2.11.1.so
7f69287fe000-7f69289fd000 ---p 0017a000 fc:00 393815
  /lib/libc-2.11.1.so
7f69289fd000-7f6928a01000 r--p 00179000 fc:00 393815
  /lib/libc-2.11.1.so
7f6928a01000-7f6928a02000 rw-p 0017d000 fc:00 393815
  /lib/libc-2.11.1.so
7f6928a02000-7f6928a07000 rw-p 00000000 00:00 0
7f6928a07000-7f6928afd000 r-xp 00000000 fc:00 131545
  /usr/lib/libstdc++.so.6.0.13
7f6928afd000-7f6928cfd000 ---p 000f6000 fc:00 131545
  /usr/lib/libstdc++.so.6.0.13
7f6928cfd000-7f6928d04000 r--p 000f6000 fc:00 131545
  /usr/lib/libstdc++.so.6.0.13
7f6928d04000-7f6928d06000 rw-p 000fd000 fc:00 131545
  /usr/lib/libstdc++.so.6.0.13
7f6928d06000-7f6928d1b000 rw-p 00000000 00:00 0
7f6928d1b000-7f6928d3b000 r-xp 00000000 fc:00 394186
  /lib/ld-2.11.1.so
7f6928f18000-7f6928f1c000 rw-p 00000000 00:00 0
7f6928f37000-7f6928f3a000 rw-p 00000000 00:00 0
7f6928f3a000-7f6928f3b000 r--p 0001f000 fc:00 394186
  /lib/ld-2.11.1.so
7f6928f3b000-7f6928f3c000 rw-p 00020000 fc:00 394186
  /lib/ld-2.11.1.so
7f6928f3c000-7f6928f3d000 rw-p 00000000 00:00 0
7fff9e35b000-7fff9e37c000 rw-p 00000000 00:00 0                          
[stack]
7fff9e3ff000-7fff9e400000 r-xp 00000000 00:00 0                          
[vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0
  [vsyscall]
Aborted



The same procedure works on many other tests, generating the correct
safecode warnings, so I'm fairly confused. Apologies if this is a dumb
question, and thanks for your time-

Geremy Condra