CVE-2024-38540 in Linux
摘要
由 VulDB • 2026-07-01
Based on the stack trace provided, here is an analysis of the issue and recommended steps to resolve it.
### **Summary** The kernel crashed (Oops/Panic) while loading the `bnxt_re` module via `init_module_from_file`. The crash occurred in user-space code (`0x7f4e5132821d`) rather than inside a specific kernel function, which strongly suggests one of two scenarios: 1. **User-Space Helper Crash:** The module init process spawned or interacted with a user-space helper (like `modprobe` or a firmware loader) that crashed due to an invalid pointer or signal. 2. **Corrupted Module Image:** The `.ko` file being loaded is corrupted, causing the kernel's module loading code to jump to an invalid address in memory.
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### **Key Observations from Stack Trace**
1. **Crash Location (`RIP: 0x7f4e5132821d`)** - The `RIP` (Instruction Pointer) is at `0x7f4e5132821d`. This address falls within the typical range of user-space shared libraries (usually starting with `0x7f...`). - **This means the crash happened in user space**, not deep inside a kernel function. The kernel was executing system calls (`__x64_sys_finit_module`) to load the module, but something went wrong during or after that call.
2. **Call Chain** ```text __pfx_bnxt_re_mod_init+0x10/0x10 [bnxt_re] <-- Module init function entry point
do_one_initcall+0x5b/0x310 <-- Kernel calls the module's init function ... <-- System call handling for finit_module __x64_sys_finit_module+0x5e/0xb0 <-- User called `finit_module` syscall ``` - The kernel successfully entered `bnxt_re_mod_init`, but then something triggered a fault that propagated back to user space or caused an unrecoverable error.
3. **Registers** - `RAX: ffffffffffffffda`: This is `-22` in signed 64-bit integer, which corresponds to the Linux error code **-EINVAL (Invalid argument)**. - However, note that this might be a return value from a failed syscall or an internal kernel check. If it were a pure NULL pointer dereference, `RAX` would likely be `0x0`. The `-22` suggests the module init function returned an error code, but **why did it cause a crash?** - Alternatively, if this is part of a signal handler or exception frame, it might indicate how the fault was handled.
4. **Module: `bnxt_re`** - This is the Broadcom NetXtreme-C/E RoCE (RDMA over Converged Ethernet) driver. - Common issues with RDMA drivers include: - Missing or incompatible firmware. - Hardware not properly initialized. - Conflicts with other network/RDMA modules.
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### **Likely Causes**
1. **Corrupted Module File (`bnxt_re.ko`)** - The `.ko` file may be incomplete, corrupted during download/copying, or compiled for a different kernel version/architecture. - When the kernel tries to execute code from this module, it jumps to an invalid address (user-space range), causing a segfault-like fault in kernel context.
2. **Firmware Loading Failure** - `bnxt_re` requires firmware files (e.g., `/lib/firmware/bnxtnet/...`). If the firmware loader fails or accesses bad memory, it could cause this crash.
3. **Kernel-Module Version Mismatch** - The module was compiled against a different kernel version than the one running (`uname -r` vs `modinfo bnxt_re.ko | grep vermagic`).
4. **User-Space Interaction Bug** - If you are using a custom tool to load the module (not just `insmod`), that tool might be crashing due to an invalid argument passed to `finit_module`.
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### **Troubleshooting Steps**
#### ✅ Step 1: Verify Module Integrity and Version Match ```bash # Check kernel version uname -r
# Check if the module matches your kernel modinfo /lib/modules/$(uname -r)/kernel/drivers/infiniband/hw/bnxt_re/bnxt_re.ko | grep vermagic
# Compare with running kernel cat /proc/version ``` - If `vermagic` does not match, **recompile the module** or install the
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