Large core dump with no function names in GDB - c++

Question

I'm fairly new to debugging core dumps on Linux, and I'm running into a weird issue. Hoping to get some suggestions.
We're getting occasional crashes on our game servers running on AWS Linux boxes. I set up the boxes to generate core dumps. Often, the dumps are around a few hundred MB -- roughly the size of the program in memory. These I'm able to load in gdb and seemingly get a valid backtrace.
But frequently, we're getting dumps that are multiple GB in size. Usually, when I load these core dumps in gdb, there's no usable info in the backtrace.
Here's an example output:
> gdb AAPGOrbis core.3871
GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.3) 7.7.1
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Reading symbols from AAPGOrbis...Reading symbols from <path to>/AAPGOrbis.dbg...done.
done.
[New LWP 3871]
[New LWP 3877]
[New LWP 6557]
[New LWP 3876]
[New LWP 6558]
[New LWP 6559]
warning: Error reading shared library list entry at 0x302e6f732e646165
warning: Error reading shared library list entry at 0x74756d5f64616572
Core was generated by `/opt/aapg/Binaries/Linux/AAPGOrbis aaentry?game=AAGame.AAGamePreGameLobbyDedica'.
Program terminated with signal SIGABRT, Aborted.
#0 0x00007fed61d001f7 in ?? ()
(gdb) bt full
#0 0x00007fed61d001f7 in ?? ()
No symbol table info available.
#1 0x00007fed61d018e8 in ?? ()
No symbol table info available.
#2 0x0000000000000020 in ?? ()
No symbol table info available.
#3 0x0000000000000000 in ?? ()
No symbol table info available.
(gdb)
Any ideas as to what might be causing this? I'm wondering if the size of the core dumps coupled with the lack of valid data is indicative of some really bad memory corruption.
Any insight would be greatly appreciated!

Answer 1

warning: Error reading shared library list entry at 0x302e6f732e646165
warning: Error reading shared library list entry at 0x74756d5f64616572
GDB is attempting to read the list of loaded shared libraries from a clearly bogus address (both of these addresses are ASCII strings ead.so.0read_mut).
The most frequent cause is that you have given GDB the wrong binary: the AAPGOrbis that you give GDB must be exactly the same binary as the one that crashed.
Another possibility is that the shared library list (which is in heap) has indeed been corrupted by the program running amok.