## Add Fuzzing Capability to Valkey

### Overview
This PR adds a fuzzing capability to Valkey, allowing developers and
users to stress test their Valkey deployments with randomly generated
commands. The fuzzer is integrated with the existing valkey-benchmark
tool, making it easy to use without requiring additional dependencies.

### Key Features
• **Command Generator**: Automatically generates Valkey commands by
retrieving command information directly from the server
• **Two Fuzzing Modes**:
- normal: Generates only valid commands, doesn't modify server
configurations
- aggressive: Includes malformed commands and allows CONFIG SET
operations

• **Multi-threaded Testing**: Each client runs in a dedicated thread to
maximize interaction between clients and enable testing of complicated
scenarios

• **Integration with valkey-benchmark**: Uses the existing CLI interface

### Implementation Details
• Added new files:
- `fuzzer_command_generator.h/c`: Dynamically generates valkey commands.
- `fuzzer_client.c`: Orchestrate all the client threads, report test
progress, and handle errors.

• Modified existing files:
  - valkey-benchmark.c: Added fuzzing mode options and integration

### Command Generation Approach
The fuzzer dynamically retrieves command information from the server,
allowing it to adapt to different Valkey versions and custom modules.
Since the command information generated from JSON files is sometimes
limited, not all generated commands will be valid, but approximately 95%
valid command generation is achieved.

It is important to generate valid commands to cover as much code path as
possible and not just the invalid command/args path. The fuzzer
prioritizes generating syntactically and semantically correct commands
to ensure thorough testing of the server's core functionality, while
still including a small percentage of invalid commands in `aggressive`
mode to test error handling paths

#### Config modification
For CONFIG SET command, the situation is more complex as the server
currently provides limited information through CONFIG GET *. Some
hardcoded logic is implemented that will need to be modified in the
future. Ideally, the server should provide self-inspection commands to
retrieve config keys-values with their properties (enum values,
modifiability status, etc.).

### Issue Detection
The fuzzer is designed to identify several types of issues:
• Server crashes
• Server memory corruptions / memory leaks(when compiled with ASAN)
• Server unresponsiveness
• Server malformed replies

For unresponsiveness detection, command timeout limits are implemented
to ensure no command blocks for excessive periods. If a server doesn't
respond within 30 seconds, the fuzzer signals that something is wrong.

### Proven Effectiveness
When running against the latest unstable version, the fuzzer has already
identified several issues, demonstrating its effectiveness:
* #2111
* #2112
* #2109
* #2113
* #2108
* #2137
* #2106
* #2347
* #2973
* #2974
### How to Use
Run the fuzzer using the valkey-benchmark tool with the --fuzz flag:

```bash
# Basic usage (10000 commands 1000 commands per client, 10 clients)
./src/valkey-benchmark --fuzz -h 127.0.0.1 -p 6379 -n 10000 -c 10

# With aggressive fuzzing mode
./src/valkey-benchmark --fuzz --fuzz-level aggressive -h 127.0.0.1 -p 6379 -n 10000 -c 10

# With detailed logging
./src/valkey-benchmark --fuzz --fuzz-log-level debug -h 127.0.0.1 -p 6379 -n 10000 -c 10
```

The fuzzer supports existing valkey-benchmark options, including TLS and
cluster mode configuration.

---------

Signed-off-by: Uri Yagelnik <uriy@amazon.com>

…xiting fields (valkey-io#2973)

When HEXPIRE commands are set with a time-in-the-past they are all
deleting the specified fields.
In such cases we allocate a temporal new argv in order to replicate
`HDEL`.
However in case no mutation was done (ie all fields do not exist) we do
not deallocate the temporal new_argv and there is a memory leak.

example:

```
HSET myhash field1 value1
1
HEXPIRE myhash 0 FIELDS 1 field2
-2
```

---------

Signed-off-by: Ran Shidlansik <ranshid@amazon.com>

## Add Fuzzing Capability to Valkey

### Overview
This PR adds a fuzzing capability to Valkey, allowing developers and
users to stress test their Valkey deployments with randomly generated
commands. The fuzzer is integrated with the existing valkey-benchmark
tool, making it easy to use without requiring additional dependencies.

### Key Features
• **Command Generator**: Automatically generates Valkey commands by
retrieving command information directly from the server
• **Two Fuzzing Modes**:
- normal: Generates only valid commands, doesn't modify server
configurations
- aggressive: Includes malformed commands and allows CONFIG SET
operations

• **Multi-threaded Testing**: Each client runs in a dedicated thread to
maximize interaction between clients and enable testing of complicated
scenarios

• **Integration with valkey-benchmark**: Uses the existing CLI interface

### Implementation Details
• Added new files:
- `fuzzer_command_generator.h/c`: Dynamically generates valkey commands.
- `fuzzer_client.c`: Orchestrate all the client threads, report test
progress, and handle errors.

• Modified existing files:
  - valkey-benchmark.c: Added fuzzing mode options and integration

### Command Generation Approach
The fuzzer dynamically retrieves command information from the server,
allowing it to adapt to different Valkey versions and custom modules.
Since the command information generated from JSON files is sometimes
limited, not all generated commands will be valid, but approximately 95%
valid command generation is achieved.

It is important to generate valid commands to cover as much code path as
possible and not just the invalid command/args path. The fuzzer
prioritizes generating syntactically and semantically correct commands
to ensure thorough testing of the server's core functionality, while
still including a small percentage of invalid commands in `aggressive`
mode to test error handling paths

#### Config modification
For CONFIG SET command, the situation is more complex as the server
currently provides limited information through CONFIG GET *. Some
hardcoded logic is implemented that will need to be modified in the
future. Ideally, the server should provide self-inspection commands to
retrieve config keys-values with their properties (enum values,
modifiability status, etc.).

### Issue Detection
The fuzzer is designed to identify several types of issues:
• Server crashes
• Server memory corruptions / memory leaks(when compiled with ASAN)
• Server unresponsiveness
• Server malformed replies

For unresponsiveness detection, command timeout limits are implemented
to ensure no command blocks for excessive periods. If a server doesn't
respond within 30 seconds, the fuzzer signals that something is wrong.

### Proven Effectiveness
When running against the latest unstable version, the fuzzer has already
identified several issues, demonstrating its effectiveness:
* valkey-io#2111
* valkey-io#2112
* valkey-io#2109
* valkey-io#2113
* valkey-io#2108
* valkey-io#2137
* valkey-io#2106
* valkey-io#2347
* valkey-io#2973
* valkey-io#2974
### How to Use
Run the fuzzer using the valkey-benchmark tool with the --fuzz flag:

```bash
# Basic usage (10000 commands 1000 commands per client, 10 clients)
./src/valkey-benchmark --fuzz -h 127.0.0.1 -p 6379 -n 10000 -c 10

# With aggressive fuzzing mode
./src/valkey-benchmark --fuzz --fuzz-level aggressive -h 127.0.0.1 -p 6379 -n 10000 -c 10

# With detailed logging
./src/valkey-benchmark --fuzz --fuzz-log-level debug -h 127.0.0.1 -p 6379 -n 10000 -c 10
```

The fuzzer supports existing valkey-benchmark options, including TLS and
cluster mode configuration.

---------

Signed-off-by: Uri Yagelnik <uriy@amazon.com>

…xiting fields (valkey-io#2973)

When HEXPIRE commands are set with a time-in-the-past they are all
deleting the specified fields.
In such cases we allocate a temporal new argv in order to replicate
`HDEL`.
However in case no mutation was done (ie all fields do not exist) we do
not deallocate the temporal new_argv and there is a memory leak.

example:

```
HSET myhash field1 value1
1
HEXPIRE myhash 0 FIELDS 1 field2
-2
```

---------

Signed-off-by: Ran Shidlansik <ranshid@amazon.com>

…xiting fields (valkey-io#2973)

When HEXPIRE commands are set with a time-in-the-past they are all
deleting the specified fields.
In such cases we allocate a temporal new argv in order to replicate
`HDEL`.
However in case no mutation was done (ie all fields do not exist) we do
not deallocate the temporal new_argv and there is a memory leak.

example:

```
HSET myhash field1 value1
1
HEXPIRE myhash 0 FIELDS 1 field2
-2
```

---------

Signed-off-by: Ran Shidlansik <ranshid@amazon.com>

…xiting fields (#2973)

When HEXPIRE commands are set with a time-in-the-past they are all
deleting the specified fields.
In such cases we allocate a temporal new argv in order to replicate
`HDEL`.
However in case no mutation was done (ie all fields do not exist) we do
not deallocate the temporal new_argv and there is a memory leak.

example:

```
HSET myhash field1 value1
1
HEXPIRE myhash 0 FIELDS 1 field2
-2
```

---------

Signed-off-by: Ran Shidlansik <ranshid@amazon.com>

…xiting fields (valkey-io#2973)

When HEXPIRE commands are set with a time-in-the-past they are all
deleting the specified fields.
In such cases we allocate a temporal new argv in order to replicate
`HDEL`.
However in case no mutation was done (ie all fields do not exist) we do
not deallocate the temporal new_argv and there is a memory leak.

example:

```
HSET myhash field1 value1
1
HEXPIRE myhash 0 FIELDS 1 field2
-2
```

---------

Signed-off-by: Ran Shidlansik <ranshid@amazon.com>
Signed-off-by: Harkrishn Patro <bunty.hari@gmail.com>

## Add Fuzzing Capability to Valkey

### Overview
This PR adds a fuzzing capability to Valkey, allowing developers and
users to stress test their Valkey deployments with randomly generated
commands. The fuzzer is integrated with the existing valkey-benchmark
tool, making it easy to use without requiring additional dependencies.

### Key Features
• **Command Generator**: Automatically generates Valkey commands by
retrieving command information directly from the server
• **Two Fuzzing Modes**:
- normal: Generates only valid commands, doesn't modify server
configurations
- aggressive: Includes malformed commands and allows CONFIG SET
operations

• **Multi-threaded Testing**: Each client runs in a dedicated thread to
maximize interaction between clients and enable testing of complicated
scenarios

• **Integration with valkey-benchmark**: Uses the existing CLI interface

### Implementation Details
• Added new files:
- `fuzzer_command_generator.h/c`: Dynamically generates valkey commands.
- `fuzzer_client.c`: Orchestrate all the client threads, report test
progress, and handle errors.

• Modified existing files:
  - valkey-benchmark.c: Added fuzzing mode options and integration

### Command Generation Approach
The fuzzer dynamically retrieves command information from the server,
allowing it to adapt to different Valkey versions and custom modules.
Since the command information generated from JSON files is sometimes
limited, not all generated commands will be valid, but approximately 95%
valid command generation is achieved.

It is important to generate valid commands to cover as much code path as
possible and not just the invalid command/args path. The fuzzer
prioritizes generating syntactically and semantically correct commands
to ensure thorough testing of the server's core functionality, while
still including a small percentage of invalid commands in `aggressive`
mode to test error handling paths

#### Config modification
For CONFIG SET command, the situation is more complex as the server
currently provides limited information through CONFIG GET *. Some
hardcoded logic is implemented that will need to be modified in the
future. Ideally, the server should provide self-inspection commands to
retrieve config keys-values with their properties (enum values,
modifiability status, etc.).

### Issue Detection
The fuzzer is designed to identify several types of issues:
• Server crashes
• Server memory corruptions / memory leaks(when compiled with ASAN)
• Server unresponsiveness
• Server malformed replies

For unresponsiveness detection, command timeout limits are implemented
to ensure no command blocks for excessive periods. If a server doesn't
respond within 30 seconds, the fuzzer signals that something is wrong.

### Proven Effectiveness
When running against the latest unstable version, the fuzzer has already
identified several issues, demonstrating its effectiveness:
* valkey-io#2111
* valkey-io#2112
* valkey-io#2109
* valkey-io#2113
* valkey-io#2108
* valkey-io#2137
* valkey-io#2106
* valkey-io#2347
* valkey-io#2973
* valkey-io#2974
### How to Use
Run the fuzzer using the valkey-benchmark tool with the --fuzz flag:

```bash
# Basic usage (10000 commands 1000 commands per client, 10 clients)
./src/valkey-benchmark --fuzz -h 127.0.0.1 -p 6379 -n 10000 -c 10

# With aggressive fuzzing mode
./src/valkey-benchmark --fuzz --fuzz-level aggressive -h 127.0.0.1 -p 6379 -n 10000 -c 10

# With detailed logging
./src/valkey-benchmark --fuzz --fuzz-log-level debug -h 127.0.0.1 -p 6379 -n 10000 -c 10
```

The fuzzer supports existing valkey-benchmark options, including TLS and
cluster mode configuration.

---------

Signed-off-by: Uri Yagelnik <uriy@amazon.com>
Signed-off-by: Harkrishn Patro <bunty.hari@gmail.com>

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [docker.io/valkey/valkey](https://github.com/valkey-io/valkey) | image | patch | `9.0.1` → `9.0.4` |

---

### Release Notes

<details>
<summary>valkey-io/valkey (docker.io/valkey/valkey)</summary>

### [`v9.0.4`](https://github.com/valkey-io/valkey/releases/tag/9.0.4)

[Compare Source](valkey-io/valkey@9.0.3...9.0.4)

Upgrade urgency SECURITY: This release includes security fixes we recommend you
apply as soon as possible.

##### Security fixes

- (CVE-2026-23479) Use-After-Free in unblock client flow
- (CVE-2026-25243) Invalid Memory Access in RESTORE command
- (CVE-2026-23631) Use-after-free when full sync occurs during a yielding Lua/function execution

### [`v9.0.3`](https://github.com/valkey-io/valkey/releases/tag/9.0.3)

[Compare Source](valkey-io/valkey@9.0.2...9.0.3)

##### Valkey 9.0.3

Upgrade urgency SECURITY: This release includes security fixes we recommend you
apply as soon as possible.

##### Security fixes

- (CVE-2025-67733) RESP Protocol Injection via Lua error\_reply
- (CVE-2026-21863) Remote DoS with malformed Valkey Cluster bus message
- (CVE-2026-27623) Reset request type after handling empty requests

##### Bug fixes

- Avoids crash during MODULE UNLOAD when ACL rules reference a module command and subcommand ([#&#8203;3160](valkey-io/valkey#3160))
- Fix server assert on ACL LOAD when current user loses permission to channels ([#&#8203;3182](valkey-io/valkey#3182))
- Fix bug causing no response flush sometimes when IO threads are busy ([#&#8203;3205](valkey-io/valkey#3205))

### [`v9.0.2`](https://github.com/valkey-io/valkey/releases/tag/9.0.2)

[Compare Source](valkey-io/valkey@9.0.1...9.0.2)

Upgrade urgency HIGH: There are critical bugs that may affect a subset of users.

#### Bug fixes

- Avoid memory leak of new argv when HEXPIRE commands target only non-exiting fields ([#&#8203;2973](valkey-io/valkey#2973))
- Fix HINCRBY and HINCRBYFLOAT to update volatile key tracking ([#&#8203;2974](valkey-io/valkey#2974))
- Avoid empty hash object when HSETEX added no fields ([#&#8203;2998](valkey-io/valkey#2998))
- Fix case-sensitive check for the FNX and FXX arguments in HSETEX ([#&#8203;3000](valkey-io/valkey#3000))
- Prevent assertion in active expiration job after a hash with volatile fields is overwritten ([#&#8203;3003](valkey-io/valkey#3003), [#&#8203;3007](valkey-io/valkey#3007))
- Fix HRANDFIELD to return null response when no field could be found ([#&#8203;3022](valkey-io/valkey#3022))
- Fix HEXPIRE to not delete items when validation rules fail and expiration is in the past ([#&#8203;3023](valkey-io/valkey#3023), [#&#8203;3048](valkey-io/valkey#3048))
- Fix how hash is handling overriding of expired fields overwrite ([#&#8203;3060](valkey-io/valkey#3060))
- HSETEX - Always issue keyspace notifications after validation ([#&#8203;3001](valkey-io/valkey#3001))
- Make zero a valid TTL for hash fields during import mode and data loading ([#&#8203;3006](valkey-io/valkey#3006))
- Trigger prepareCommand on argc change in module command filters ([#&#8203;2945](valkey-io/valkey#2945))
- Restrict TTL from being negative and avoid crash in import-mode ([#&#8203;2944](valkey-io/valkey#2944))
- Fix chained replica crash when doing dual channel replication ([#&#8203;2983](valkey-io/valkey#2983))
- Skip slot cache optimization for AOF client to prevent key duplication and data corruption ([#&#8203;3004](valkey-io/valkey#3004))
- Fix used\_memory\_dataset underflow due to miscalculated used\_memory\_overhead ([#&#8203;3005](valkey-io/valkey#3005))
- Avoid duplicate calculations of network-bytes-out in slot stats with copy-avoidance ([#&#8203;3046](valkey-io/valkey#3046))
- Fix XREAD returning error on empty stream with + ID ([#&#8203;2742](valkey-io/valkey#2742))

#### Performance/Efficiency Improvements

- Track reply bytes in I/O threads if commandlog-reply-larger-than is -1 ([#&#8203;3086](valkey-io/valkey#3086), [#&#8203;3126](valkey-io/valkey#3126)).
  This makes it possible to mitigate a performance regression in 9.0.1 caused by the bug fix [#&#8203;2652](valkey-io/valkey#2652).

**Full Changelog**: <valkey-io/valkey@9.0.1...9.0.2>

</details>

---

### Configuration

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♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

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---

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