Hi,
We are using lxml in several of our applications with Python 2.6 and from time to time, the application stops responding after a segmentation fault error, and this kind of backtrace:
Jul 1 15:35:01 server4 httpd: *** glibc detected *** /usr/sbin/apache2: malloc(): smallbin double linked list corrupted: 0x00007f583a03f500 ***
Jul 1 15:35:01 server4 httpd: ======= Backtrace: =========
Jul 1 15:35:01 server4 httpd: /lib/libc.so.6(+0x77806)[0x7f58376c2806]
Jul 1 15:35:01 server4 httpd: /lib/libc.so.6(+0x7bb39)[0x7f58376c6b39]
Jul 1 15:35:01 server4 httpd: /lib/libc.so.6(__libc_malloc+0x6e)[0x7f58376c77de]
Jul 1 15:35:01 server4 httpd: /usr/lib/libxml2.so.2(xmlInitParserCtxt+0x317)[0x7f58343f2887]
Jul 1 15:35:01 server4 httpd: /usr/lib/libxml2.so.2(xmlNewParserCtxt+0x2c)[0x7f58343f2acc]
Jul 1 15:35:01 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0x54eda)[0x7f5818db6eda]
Jul 1 15:35:01 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0xddcf3)[0x7f5818e3fcf3]
Jul 1 15:35:01 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0xab5ee)[0x7f5818e0d5ee]
Jul 1 15:35:01 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0xb7d8e)[0x7f5818e19d8e]
Jul 1 15:35:01 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0xb827e)[0x7f5818e1a27e]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalFrameEx+0x51a0)[0x7f582face030]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalFrameEx+0x5a98)[0x7f582face928]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalCodeEx+0x920)[0x7f582facfd60]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0x7dd60)[0x7f582fa55d60]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f582fa282e3]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalFrameEx+0x3adf)[0x7f582facc96f]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalCodeEx+0x920)[0x7f582facfd60]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0x7dd60)[0x7f582fa55d60]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f582fa282e3]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0x61cef)[0x7f582fa39cef]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f582fa282e3]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0xb66dc)[0x7f582fa8e6dc]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f582fa282e3]
Jul 1 15:35:01 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_CallObjectWithKeywords+0x43)[0x7f582fac8193]
Jul 1 15:35:01 server4 httpd: /usr/lib/apache2/modules/mod_wsgi.so(+0x12fdb)[0x7f582fe9bfdb]
Jul 1 15:35:01 server4 httpd: /usr/lib/apache2/modules/mod_wsgi.so(+0x17eed)[0x7f582fea0eed]
Jul 1 15:35:01 server4 httpd: /usr/lib/libapr-1.so.0(+0x29eb3)[0x7f5837c14eb3]
Jul 1 15:35:01 server4 httpd: /lib/libpthread.so.0(+0x69ca)[0x7f58379d49ca]
Jul 1 15:35:01 server4 httpd: /lib/libc.so.6(clone+0x6d)[0x7f5837731cdd]
-----------------
Jul 11 10:44:48 server4 httpd: *** glibc detected *** /usr/sbin/apache2: munmap_chunk(): invalid pointer: 0x00007f3968b8cb68 ***
Jul 11 10:44:48 server4 httpd: ======= Backtrace: =========
Jul 11 10:44:48 server4 httpd: /lib/libc.so.6(+0x77806)[0x7f39789dd806]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(xmlResetError+0x22)[0x7f39755038e2]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(__xmlRaiseError+0x237)[0x7f3975504e07]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(__xmlSimpleError+0x6b)[0x7f397550543b]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(xmlParserInputBufferGrow+0x16b)[0x7f397553271b]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(xmlParserInputGrow+0x4c)[0x7f397550739c]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(+0x3bd52)[0x7f397550bd52]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(xmlParseDocument+0x4b8)[0x7f39755204c8]
Jul 11 10:44:48 server4 httpd: /usr/lib/libxml2.so.2(+0x505c5)[0x7f39755205c5]
Jul 11 10:44:48 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0x8fab0)[0x7f3958ad8ab0]
Jul 11 10:44:48 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0x2daa0)[0x7f3958a76aa0]
Jul 11 10:44:48 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0x2ddc9)[0x7f3958a76dc9]
Jul 11 10:44:48 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0xc26f0)[0x7f3958b0b6f0]
Jul 11 10:44:48 server4 httpd: /usr/lib/python2.6/dist-packages/lxml/etree.so(+0xc431e)[0x7f3958b0d31e]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalFrameEx+0x51a0)[0x7f397063b030]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalCodeEx+0x920)[0x7f397063cd60]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0x7dd60)[0x7f39705c2d60]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f39705952e3]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalFrameEx+0x3adf)[0x7f397063996f]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_EvalCodeEx+0x920)[0x7f397063cd60]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0x7dd60)[0x7f39705c2d60]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f39705952e3]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0x61cef)[0x7f39705a6cef]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f39705952e3]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(+0xb66dc)[0x7f39705fb6dc]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyObject_Call+0x53)[0x7f39705952e3]
Jul 11 10:44:48 server4 httpd: /usr/lib/libpython2.6.so.1.0(PyEval_CallObjectWithKeywords+0x43)[0x7f3970635193]
Jul 11 10:44:48 server4 httpd: /usr/lib/apache2/modules/mod_wsgi.so(+0x12fdb)[0x7f3970a08fdb]
Jul 11 10:44:48 server4 httpd: /usr/lib/apache2/modules/mod_wsgi.so(+0x17eed)[0x7f3970a0deed]
Jul 11 10:44:48 server4 httpd: /usr/lib/libapr-1.so.0(+0x29eb3)[0x7f3978f2feb3]
Jul 11 10:44:48 server4 httpd: /lib/libpthread.so.0(+0x69ca)[0x7f3978cef9ca]
Jul 11 10:44:48 server4 httpd: /lib/libc.so.6(clone+0x6d)[0x7f3978a4ccdd]
Stopping apache and restarting it fix the issue, but we have no idea why this is happening.We use Unbuntu 10.10's package of lxml, which is version 2.2.4.
>>> print("%-20s: %s" % ('Python', sys.version_info))
Python : (2, 6, 5, 'final', 0)
>>> print("%-20s: %s" % ('lxml.etree', etree.LXML_VERSION))
lxml.etree : (2, 2, 4, 0)
>>> print("%-20s: %s" % ('libxml used', etree.LIBXML_VERSION))
libxml used : (2, 7, 6)
>>> print("%-20s: %s" % ('libxml compiled', etree.LIBXML_COMPILED_VERSION))
libxml compiled : (2, 7, 6)
>>> print("%-20s: %s" % ('libxslt used', etree.LIBXSLT_VERSION))
libxslt used : (1, 1, 26)
>>> print("%-20s: %s" % ('libxslt compiled', etree.LIBXSLT_COMPILED_VERSION))
libxslt compiled : (1, 1, 26)
Do you have any idea of what could cause these issues ? I wonder if upgrading to a newer version of the library could change anything.
Thanks in advance for any answer you could provide.
Regards,
B.
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Brieuc SCHAFF
+33609898260
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