Dr. Memory internal crash

[RuurdBeerstra]

Describe the bug While trying to detect memory issues in my program, DrMemory crashed and asked me to report this: <Application i:\ivt\work\ivt.exe (4768). Dr. Memory internal crash at PC 0x00000000710cbc4b. Please report this at http://drmemory.org/issues along with the results of running '-debug -dr_debug'. Program aborted. 0xc0000005 0x00000000 0x00000000710cbc4b 0x00000000710cbc4b 0x0000000000000001 0x000000007118dcbc Base: 0x0000000071000000 Registers: eax=0x0000000000000001 ebx=0x0000016663c64a80 ecx=0xffffffffffffffff edx=0x0000000000000001 esi=0x00000040407ff208 edi=0x0000000000000000 esp=0x00000040407ff0c8 ebp=0x0000000000000000 r8 =0x0000000000000000 r9 =0x0000000000000000 r10=0x0000000000000000 r11=0x0000000000000246 r12=0x0000000000000001 r13=0x0000000000000000 r14=0x00000040407ff700 r15=0x0000000000000000 eflags=0x0000000000010286 2.3.0-1-(Feb 6 2020 06:07:09) WinVer=105;Rel=2004;Build=19041;Edition=Core -no_dynamic_options -disasm_mask 8 -logdir 'C:\Users\ruurd\AppData\Roaming\Dr. Memory\dynamorio' -client_lib 'C:\Program Files (x86)\Dr. Memory\bin64\release\drmemorylib.dll;0;-no_check_gdi -logdir C:\Users\ruurd\AppData\Roaming\Dr. Memory -symcache_dir C:\Users\ruurd\AppData\Roaming\Dr. Memory\symcache -lib_blackl> ~~Dr.M~~ Fetching 1 symbol files... ~~Dr.M~~ [1/1] Fetching symbols for C:\WINDOWS\System32\msvcrt.dll WARNING: drfront_sym_exit failed 6 ~~Dr.M~~ Fetched 0 symbol files successfully ~~Dr.M~~ WARNING: application exited with abnormal code 0xffffffff

To Reproduce Steps to reproduce the behavior: Happens every time I start my (private, sorry) application. Command line:

drmemory -no_check_gdi -- ivt

Please also answer these questions drawn from https://github.com/DynamoRIO/drmemory/wiki/Debugging#narrowing-down-the-source-of-the-problem :

• Does the problem go away when running in light mode (pass -light to Dr. Memory)? No: It crashes much faster, the first call first shows a bunch of uninitialized reads.

• Does the problem go away when running with the options -leaks_only -no_count_leaks -no_track_allocs? No also crashes,

• Does the problem go away when running under plain DynamoRIO? Do this by running dynamorio/bin32/drrun -- <application and args> or dynamorio/bin64/drrun -- <application and args> depending on the bitwidth of your applicaiton. (Ignore warnings about "incomplete installation".) It complains about log-dir it cannot make, my binary seems to run at normal speed, no issues reported, no crash.

![image](https://user-images.githubusercontent.com/45171310/88211234-b342b000-cc55-11ea-9966-fde24445f26b.png)

• What happens with the debug version of Dr. Memory and of its underlying engine DynamoRIO? Try this by passing -debug -dr_debug -pause_at_assert. Are any messages reported? It pops up with an ASSERT FAILURE: ASSERT FAILURE (thread 3544): D:\drmemory_package\drmemory\fastpath_x86.c:1004: mi->memsz <= 4 (load2x of 8-byte memop not supported)

Expected behavior A clear and concise description of what you expected to happen. I had hoped to detect memory issues in MY application, not yours :-)

Screenshots or Pasted Text If applicable, add screenshots to help explain your problem. For text, please cut and paste the text here, delimited by lines consisting of three backtics to render it verbatim, like this:

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Versions

• What version of Dr. Memory are you using? DrMemory-Windows-2.3.0-1.msi

• Does the latest build from https://github.com/DynamoRIO/drmemory/wiki/Latest-Build solve the problem? I upgraded to this latest version to see if it could find new problems...

• What operating system version are you running on? ("Windows 10" is not sufficient: give the release number.) Microsoft Windows [Version 10.0.19041.388]

• Is your application 32-bit or 64-bit? 64

Additional context Add any other context about the problem here.

[derekbruening]

ASSERT fastpath_x86.c:1004: mi->memsz <= 4 (load2x of 8-byte memop not supported) is #2183