[LLDB][Minidump] Fix bug in generating 64b memory minidumps

[Jlalond]

In #129307, we introduced read write in chunks, and during the final revision of the PR I changed the behavior for 64b memory regions and did not test an actual 64b memory range.

This caused LLDB to crash whenever we generated a 64b memory region.

64b regions has been a problem in testing for some time as it's a waste of test resources to generation a 5gb+ Minidump. I will work with @clayborg and @labath to come up with a way to specify creating a 64b list instead of a 32b list (likely via the yamilizer).

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Jacob Lalonde (Jlalond)

Changes

In #129307, we introduced read write in chunks, and during the final revision of the PR I changed the behavior for 64b memory regions and did not test an actual 64b memory range.

This caused LLDB to crash whenever we generated a 64b memory region.

64b regions has been a problem in testing for some time as it's a waste of test resources to generation a 5gb+ Minidump. I will work with @clayborg and @labath to come up with a way to specify creating a 64b list instead of a 32b list (likely via the yamilizer).

---

Full diff: https://github.com/llvm/llvm-project/pull/141995.diff

1 Files Affected:

• (modified) lldb/source/Plugins/ObjectFile/Minidump/MinidumpFileBuilder.cpp (+2-1)

diff --git a/lldb/source/Plugins/ObjectFile/Minidump/MinidumpFileBuilder.cpp b/lldb/source/Plugins/ObjectFile/Minidump/MinidumpFileBuilder.cpp
index 2818d31eb2301..806f256d9da48 100644
--- a/lldb/source/Plugins/ObjectFile/Minidump/MinidumpFileBuilder.cpp
+++ b/lldb/source/Plugins/ObjectFile/Minidump/MinidumpFileBuilder.cpp
@@ -1170,7 +1170,6 @@ MinidumpFileBuilder::AddMemoryList_64(std::vector<CoreFileMemoryRange> &ranges,
               "(%" PRIx64 "bytes) "
               "[%" PRIx64 ", %" PRIx64 ")",
               region_index, ranges.size(), size, addr, addr + size);
-    ++region_index;
 
     progress.Increment(1, "Adding Memory Range " + core_range.Dump());
     uint64_t bytes_read = 0;
@@ -1186,6 +1185,8 @@ MinidumpFileBuilder::AddMemoryList_64(std::vector<CoreFileMemoryRange> &ranges,
       cleanup_required = true;
       descriptors[region_index].DataSize = bytes_read;
     }
+
+    ++region_index;
   }
 
   // Early return if there is no cleanup needed.

[Jlalond]

MINIDUMP_MEMORY64_LIST:
NumberOfMemoryRanges = 0x0000000000000042
BaseRva              = 0x00007f1963c00000
MemoryRanges[0]      = [0x0000000000000000 - 0x00007f1a40200000)
MemoryRanges[1]      = [0x0000000000000000 - 0x00007f1e08200000)
MemoryRanges[2]      = [0x0000000000000000 - 0x00007f20c960d000)
MemoryRanges[3]      = [0x0000000000000000 - 0x00007f2de3c00000)
MemoryRanges[4]      = [0x0000000000000000 - 0x00007f2df22f0000)
MemoryRanges[5]      = [0x0000000000001000 - 0x00007f2df22f2000)
MemoryRanges[6]      = [0x0000000000002000 - 0x00007f2df22f5000)
MemoryRanges[7]      = [0x0000000000000000 - 0x00007f2df22f6000)
MemoryRanges[8]      = [0x0000000000000000 - 0x00007f2df22ff000)
MemoryRanges[9]      = [0x0000000000000000 - 0x00007f2df2303000)
MemoryRanges[10]     = [0x0000000000001000 - 0x00007f2df2305000)
MemoryRanges[11]     = [0x0000000000000000 - 0x00007f2df2326000)
MemoryRanges[12]     = [0x0000000000000000 - 0x00007f2df238e000)
MemoryRanges[13]     = [0x0000000000000000 - 0x00007f2df23de000)
MemoryRanges[14]     = [0x0000000000003000 - 0x00007f2df23e4000)
MemoryRanges[15]     = [0x0000000000000000 - 0x00007f2df23e6000)
MemoryRanges[16]     = [0x0000000000000000 - 0x00007f2df23f8000)
MemoryRanges[17]     = [0x0000000000000000 - 0x00007f2df23fd000)
MemoryRanges[18]     = [0x0000000000002000 - 0x00007f2df2401000)
MemoryRanges[19]     = [0x0000000000001000 - 0x00007f2df2401000)
MemoryRanges[20]     = [0x0000000000000000 - 0x00007f2df43d6000)
MemoryRanges[21]     = [0x0000000000000000 - 0x00007f2df820c000)
MemoryRanges[22]     = [0x0000000000288000 - 0x00007f2df871c000)
MemoryRanges[23]     = [0x0000000000136000 - 0x00007f2df8701000)
MemoryRanges[24]     = [0x0000000000008000 - 0x00007f2df85db000)
MemoryRanges[25]     = [0x0000000000000000 - 0x00007f2df85d6000)
MemoryRanges[26]     = [0x0000000000000000 - 0x00007f2df85dd000)
MemoryRanges[27]     = [0x0000000000000000 - 0x00007f2df85e1000)
MemoryRanges[28]     = [0x0000000000001000 - 0x00007f2df85e3000)
MemoryRanges[29]     = [0x0000000000000000 - 0x00007f2df85ed000)
MemoryRanges[30]     = [0x0000000000000000 - 0x00007f2df861f000)
MemoryRanges[31]     = [0x0000000000000000 - 0x00007f2df8629000)
MemoryRanges[32]     = [0x0000000000002000 - 0x00007f2df862d000)
MemoryRanges[33]     = [0x0000000000004000 - 0x00007f2df8633000)
MemoryRanges[34]     = [0x0000000000000000 - 0x00007f2df8630000)
MemoryRanges[35]     = [0x0000000000000000 - 0x00007f2df8631000)
MemoryRanges[36]     = [0x0000000000000000 - 0x00007f2df8633000)
MemoryRanges[37]     = [0x0000000000001000 - 0x00007f2df8635000)
MemoryRanges[38]     = [0x0000000000000000 - 0x00007f2df8637000)
MemoryRanges[39]     = [0x0000000000000000 - 0x00007f2df8649000)
MemoryRanges[40]     = [0x0000000000000000 - 0x00007f2df864d000)
MemoryRanges[41]     = [0x0000000000003000 - 0x00007f2df8653000)
MemoryRanges[42]     = [0x0000000000000000 - 0x00007f2df8653000)
MemoryRanges[43]     = [0x0000000000000000 - 0x00007f2df866f000)
MemoryRanges[44]     = [0x0000000000000000 - 0x00007f2df867a000)
MemoryRanges[45]     = [0x0000000000001000 - 0x00007f2df867c000)
MemoryRanges[46]     = [0x0000000000001000 - 0x00007f2df867d000)
MemoryRanges[47]     = [0x0000000000000000 - 0x00007f2df868a000)
MemoryRanges[48]     = [0x0000000000000000 - 0x00007f2df869b000)
MemoryRanges[49]     = [0x0000000000000000 - 0x00007f2df86ac000)
MemoryRanges[50]     = [0x0000000000001000 - 0x00007f2df86ae000)
MemoryRanges[51]     = [0x0000000000000000 - 0x00007f2df86af000)
MemoryRanges[52]     = [0x0000000000000000 - 0x00007f2df86bf000)
MemoryRanges[53]     = [0x0000000000000000 - 0x00007f2df86c6000)
MemoryRanges[54]     = [0x0000000000001000 - 0x00007f2df86c8000)
MemoryRanges[55]     = [0x0000000000000000 - 0x00007f2df86d6000)
MemoryRanges[56]     = [0x0000000000000000 - 0x00007f2df8748000)
MemoryRanges[57]     = [0x0000000000000000 - 0x00007f2df87a0000)
MemoryRanges[58]     = [0x0000000000003000 - 0x00007f2df87a6000)
MemoryRanges[59]     = [0x0000000000004000 - 0x00007f2df87ab000)
MemoryRanges[60]     = [0x0000000000002000 - 0x00007f2df87ab000)
MemoryRanges[61]     = [0x0000000000000000 - 0x00007f2df87aa000)
MemoryRanges[62]     = [0x0000000000000000 - 0x00007f2df87d3000)
MemoryRanges[63]     = [0x0000000000000000 - 0x00007f2df87df000)
MemoryRanges[64]     = [0x0000000000022000 - 0x00007ffc7e2ce000)
MemoryRanges[65]     = [0x0000000000003000 - 0x0000000000006000)

Tested against a process with 64b memory