Description

In the Linux kernel, the following vulnerability has been resolved: clk: clk-loongson2: Fix potential buffer overflow in flexible-array member access Flexible-array member `hws` in `struct clk_hw_onecell_data` is annotated with the `counted_by()` attribute. This means that when memory is allocated for this array, the _counter_, which in this case is member `num` in the flexible structure, should be set to the maximum number of elements the flexible array can contain, or fewer. In this case, the total number of elements for the flexible array is determined by variable `clks_num` when allocating heap space via `devm_kzalloc()`, as shown below: 289 struct loongson2_clk_provider *clp; ... 296 for (p = data; p->name; p++) 297 clks_num++; 298 299 clp = devm_kzalloc(dev, struct_size(clp, clk_data.hws, clks_num), 300 GFP_KERNEL); So, `clp->clk_data.num` should be set to `clks_num` or less, and not exceed `clks_num`, as is currently the case. Otherwise, if data is written into `clp->clk_data.hws[clks_num]`, the instrumentation provided by the compiler won't detect the overflow, leading to a memory corruption bug at runtime. Fix this issue by setting `clp->clk_data.num` to `clks_num`.

Weaknesses 1

Affected Products 2

References 3

• git.kernel.org https://git.kernel.org/stable/c/02fb4f0084331ef72c28d0c70fcb15d1bea369ec
  Patch
• git.kernel.org https://git.kernel.org/stable/c/1bf8877150128c3abd9d233886a05f6966fbf0c7
  Patch
• git.kernel.org https://git.kernel.org/stable/c/b96fc194984d0c82de1ca2b4166b35b1298b216c
  Patch

Remediation

• git.kernel.org https://git.kernel.org/stable/c/02fb4f0084331ef72c28d0c70fcb15d1bea369ec
  Patch
• git.kernel.org https://git.kernel.org/stable/c/1bf8877150128c3abd9d233886a05f6966fbf0c7
  Patch
• git.kernel.org https://git.kernel.org/stable/c/b96fc194984d0c82de1ca2b4166b35b1298b216c
  Patch