C-blosc2 before 2.9.3 was discovered to contain a NULL pointer dereference via the function zfp_rate_decompress at zfp/blosc2-zfp.c.
**Describe the bug**
Null Pointer Dereferencing at line **641** in [plugins/codecs/zfp/blosc2-zfp.c](https://github.com/Blosc/c-blosc2/blob/86fc0f66aa6dd079dbf79d775dc9dc1462830ffd/plugins/codecs/zfp/blosc2-zfp.c#L641). This is caused due to using a pointer to a chunk which does not exist. This bug is in function `zfp_rate_decompress`.

**To Reproduce**
Run the fuzzing harness in tests/fuzz `fuzz_decompress_chunk` with the attached input (in Zip File)
[null-ptr-3.zip](https://github.com/Blosc/c-blosc2/files/11807499/null-ptr-3.zip)

**Expected behavior**
Check whether the chunk is a correct pointer at line 640.

**Logs**
If applicable, add logs to help explain your problem.

**System information:**
 - OS: Ubuntu 20.04
 - Compiler: clang-11
 - Version: Latest commit on `main` branch

**Additional context**
This bug has been found by fuzzing.
Null Pointer Dereferencing bug in plugins/codecs/zfp/blosc2-zfp.c
This is a GitHub Issue
repo:c-blosc2
owner:Blosc
Title : Null Pointer Dereferencing bug in plugins/codecs/zfp/blosc2-zfp.c
Issue date:

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**Describe the bug**
Null Pointer Dereferencing at line **641** in [plugins/codecs/zfp/blosc2-zfp.c](https://github.com/Blosc/c-blosc2/blob/86fc0f66aa6dd079dbf79d775dc9dc1462830ffd/plugins/codecs/zfp/blosc2-zfp.c#L641). This is caused due to using a pointer to a chunk which does not exist. This bug is in function `zfp_rate_decompress`.

**To Reproduce**
Run the fuzzing harness in tests/fuzz `fuzz_decompress_chunk` with the attached input (in Zip File)
[null-ptr-3.zip](https://github.com/Blosc/c-blosc2/files/11807499/null-ptr-3.zip)

**Expected behavior**
Check whether the chunk is a correct pointer at line 640.

**Logs**
If applicable, add logs to help explain your problem.

**System information:**
 - OS: Ubuntu 20.04
 - Compiler: clang-11
 - Version: Latest commit on `main` branch

**Additional context**
This bug has been found by fuzzing.
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