Red Hat Bugzilla – Bug 86432
Update to glibc-2.3.2-4.80 breaks netscape communicator
Last modified: 2016-11-24 09:57:37 EST
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3) Gecko/20030314 Description of problem: After upgrade to glibc-2.3.2-4.80 netscape give Bus Error at invocation time. Version-Release number of selected component (if applicable): glibc-2.3.2-4.80 How reproducible: Always Steps to Reproduce: 1. type netscape and press enter ;-) Actual Results: Bus error Expected Results: Netscape Communicator window appears Additional info: A gdb session reveal that _pthread_cleanup_upto is the location of the segmentation fault: $ gdb /usr/lib/netscape/netscape-communicator GNU gdb Red Hat Linux (5.2.1-4) Copyright 2002 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i386-redhat-linux"... (no debugging symbols found)... (gdb) r Starting program: /usr/lib/netscape/netscape-communicator (no debugging symbols found)...(no debugging symbols found)... (no debugging symbols found)...(no debugging symbols found)... (no debugging symbols found)...(no debugging symbols found)... (no debugging symbols found)...(no debugging symbols found)... (no debugging symbols found)...[New Thread 16384 (LWP 1388)] Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 16384 (LWP 1388)] 0x407f492f in __pthread_cleanup_upto () from /lib/libpthread.so.0 (gdb) c Continuing. Program received signal SIGBUS, Bus error. 0x40239f81 in kill () from /lib/libc.so.6 Kernel running is vanilla 2.4.20 but also trying with 2.4.18-27.8.0 from Redhat Updates netscape gives the same error.
Can you please try ftp://people.redhat.com/jakub/glibc/errata/8.0/ ?
I get exactly the same results also after installing RPMS in ftp://people.redhat.com/jakub/glibc/errata/8.0/ as you suggest. I've also tried to reboot the machine after this test upgrade, but nothing has changed.
One more attempt: ftp://people.redhat.com/jakub/glibc/errata/8.0/*4.80.3* There were apparently more things needed on kernels which provide broken AT_PLATFORM aux vector element.
Using 4.80.3 as you suggest I get the following results: $ /usr/bin/netscape Bus error _but_ $ /usr/lib/netscape/netscape-communicator works. I've traced the culprit in: $ LD_ASSUME_KERNEL=2.2.5 /usr/lib/netscape/netscape-communicator Bus error Does this means this is a bug in netscape wrapper script?
The latter command line makes the runtime use a glibc with an older ABI. The difference is in how thread stacks are handled. It seems the netscape version relies on something weird in the memory layout. This certainly isn't guaranteed. Given how badly the netscpae 4 code was (judging from the first mozilla code) I am not at all surprised. If the code without LD_ASSUME_KERNEL works, fine, use it. It's not worth spending time on the other case. Use mozilla with has much better code and actually works. I'm closing the bug. I don't think there is anything we should do. Reopen if you disagree and have a proposal for how to go forward.
Created attachment 102306 [details] gdb traceback, instruction decode, reg value, NULL pointer reference This problem is reproducible with pthreaded code. It involves attempting a longjmp from a signal handler after SIGSEGV. It seems to depend on where the setjmp() was done i.e., not all SIGSEGV handling cause it. Core file is available.