From c82907153eaa584f9701f5ba1406ac50a0c73b17 Mon Sep 17 00:00:00 2001
From: AlexGuo1998 <AlexGuo1998@163.com>
Date: Thu, 2 Jan 2025 16:42:28 +0800
Subject: [PATCH] fix: Set LZMA decompressor memory limit to 1GiB (#2044)

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### Problem description
<!-- Describe the bug that you fixed/feature request that you
implemented, or link to an existing issue describing it -->

See #2033 (`hex::dec::lzma_decompress` reports an error when
decompressing a small buffer).

### Implementation description
<!-- Explain what you did to correct the problem -->

Set the LZMA decompressor memory limit to 1GiB fixed. Print a warning
when exceeded, and abort with returning `false`.

### Screenshots
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make before/after sceenshots -->

Normal result when decompressing a small buffer


![image](https://github.com/user-attachments/assets/5b9e6b07-464e-41f6-bdc7-f5b1cd351069)

Warning message when `memlimit` is exceeded: (Set to 64B here for a
demo)
> W: lzma_decompress memory usage 1114168 bytes would exceed the limit
(64 bytes), aborting


![image](https://github.com/user-attachments/assets/04abf3ef-1d29-4846-bb41-214695c7d09c)

### Additional things
<!-- Anything else you would like to say -->

Is the warning wording OK? I'm not a native English speaker so please
change it if you want to.
---
 plugins/decompress/source/content/pl_functions.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/plugins/decompress/source/content/pl_functions.cpp b/plugins/decompress/source/content/pl_functions.cpp
index d6bc01c4f..0e4f0b6de 100644
--- a/plugins/decompress/source/content/pl_functions.cpp
+++ b/plugins/decompress/source/content/pl_functions.cpp
@@ -155,7 +155,8 @@ namespace hex::plugin::decompress {
                 auto &section = evaluator->getSection(params[1].toUnsigned());
 
                 lzma_stream stream = LZMA_STREAM_INIT;
-                if (lzma_auto_decoder(&stream, 0x10000, LZMA_IGNORE_CHECK) != Z_OK) {
+                constexpr int64_t memlimit = 0x40000000;  // 1GiB
+                if (lzma_auto_decoder(&stream, memlimit, LZMA_IGNORE_CHECK) != LZMA_OK) {
                     return false;
                 }
 
@@ -179,8 +180,8 @@ namespace hex::plugin::decompress {
 
                     if (res == LZMA_MEMLIMIT_ERROR) {
                         auto usage = lzma_memusage(&stream);
-                        lzma_memlimit_set(&stream, usage);
-                        res = lzma_code(&stream, LZMA_RUN);
+                        evaluator->getConsole().log(pl::core::LogConsole::Level::Warning, fmt::format("lzma_decompress memory usage {} bytes would exceed the limit ({} bytes), aborting", usage, memlimit));
+                        return false;
                     }
 
                     if (res != LZMA_OK)