Bug: SIGSEGV in OPENSSL_cleanse

Jan Jancar johny at neuromancer.sk
Mon May 22 19:54:53 CEST 2017


Hi all.

I am, or rather was, running an instance of cgit on an ARM box:

> uname -srm
Linux 4.9.28-2-ARCH armv6l

I run ArchLinuxARM and they recently had an update to openssl:

openssl		1.1.0.e-1
openssl-1.0	1.0.2.k-3

So I currently have 2 versions of openssl on that box.

After running cgit for awhile I noticed it now SIGSEGVs on certain requests:

           PID: 12517 (cgit.cgi)
           UID: 33 (http)
           GID: 33 (http)
        Signal: 11 (SEGV)
     Timestamp: Sun 2017-05-21 13:26:35 CEST (1 day 6h ago)
  Command Line: /usr/lib/cgit/cgit.cgi
    Executable: /usr/lib/cgit/cgit.cgi
 Control Group: /system.slice/system-uwsgi.slice/uwsgi at cgit.service
          Unit: uwsgi at cgit.service
         Slice: system-uwsgi.slice
       Boot ID: 93dadbde0e144f3ab346f1e21ac7ee5d
    Machine ID: 4bd17fc498ad478094fa58c3a7782769
      Hostname: Neuromancer
       Storage:
/var/lib/systemd/coredump/core.cgit\x2ecgi.33.93dadbde0e144f3ab346f1e21ac7ee5d.12517.1495365995000000000000.lz4
       Message: Process 12517 (cgit.cgi) of user 33 dumped core.

                Stack trace of thread 12517:
                #0  0x000000007678e7d8 OPENSSL_cleanse
(/usr/lib/libcrypto.so.1.0.0)


A bit more of the stack is shown when running the dump through gdb:

#0  0x765c37d8 in OPENSSL_cleanse () from /usr/lib/libcrypto.so.1.0.0
#1  0x7664243c in EVP_MD_CTX_cleanup () from /usr/lib/libcrypto.so.1.0.0
#2  0x76642774 in EVP_MD_CTX_destroy () from /usr/lib/libcrypto.so.1.0.0
Backtrace stopped: previous frame identical to this frame (corrupt stack?)


Investigating more, some weird behavior is shown, while ldd says
cgit.cgi will run with /usr/lib/libcrypto.so.1.0.0 and even the coredump
confirms that, when actually debugging the coredump, `info sharedlib` says:

warning: Corrupted shared library list: 0x76ffa8b0 != 0x0
From        To          Syms Read   Shared Object Library
0x76fcf8f0  0x76feaaf0  Yes (*)     /lib/ld-linux-armhf.so.3
0x76e47000  0x76f6f794  Yes (*)     /usr/lib/libcrypto.so.1.1
0x76dcdb88  0x76dda8a0  Yes (*)     /usr/lib/libz.so.1
0x76da5190  0x76db6ce4  Yes (*)     /usr/lib/libpthread.so.0
0x76d8b7d0  0x76d8f418  Yes (*)     /usr/lib/librt.so.1
0x76d20580  0x76d74288  Yes (*)     /usr/lib/libluajit-5.1.so.2
0x76d09a30  0x76d0a944  Yes (*)     /usr/lib/libdl.so.2
0x76bd41f0  0x76cd4920  Yes (*)     /usr/lib/libc.so.6
0x76b3c680  0x76b776f0  Yes (*)     /usr/lib/libm.so.6
0x76b18180  0x76b26930  Yes         /usr/lib/libgcc_s.so.1

After that, setting LD_PRELOAD=/usr/lib/libcrypto.so.1.0
actually fixes the problem. So is cgit incompatible with openssl 1.1
or is there some other bug hiding?


Cheers,
-- 
Jan
______________________________________________________
   /\  # PGP: 362056ADA8F2F4E421565EF87F4A448FE68F329D
  /__\  # https://neuromancer.sk
 /\  /\  # Eastern Seaboard Phishing Authority
/__\/__\  #

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 862 bytes
Desc: OpenPGP digital signature
URL: <http://lists.zx2c4.com/pipermail/cgit/attachments/20170522/a40aecd7/attachment.asc>


More information about the CGit mailing list