جزئیات آسیب‌پذیری

In the Linux kernel, the following vulnerability has been resolved: ASoC: meson: Keep link pointers valid on realloc failure meson_card_reallocate_links() grows the DAI link and private data arrays with two consecutive krealloc() calls and updates the owner pointers only after both calls have succeeded. A successful krealloc() may move the data: it frees the old block and returns a new one. When that happens for the link array and the second krealloc() then fails, card->dai_link still points to the block that krealloc() already freed, and the error path frees the new block too. The probe error path then calls meson_card_clean_references(), which dereferences card->dai_link and kfree()s it again, resulting in a use-after-free and a double free. Commit card->dai_link and card->num_links right after the first krealloc() succeeds, so the pointer always refers to a valid allocation that meson_card_clean_references() can walk and free. krealloc() with __GFP_ZERO zero-initializes the added entries, so walking them on the error path is safe. With both failure paths reduced to a plain return, drop the goto labels and the error message.

• https://git.kernel.org/stable/c/de33afc57f24538186bccf4c4f6c65dd38634fd8
• https://git.kernel.org/stable/c/1c1485343b7c1c39dab7ecb9cd16ba49fd0ce642
• https://git.kernel.org/stable/c/8db0a0fc84e80aa9924e0833aef6cc95df94e5a7
• https://git.kernel.org/stable/c/41e92e0caa1fe3df2efaca346bfcaeb7fb9826ab
• https://git.kernel.org/stable/c/0b30fbe6bf7cf6499b19dd886f466e7c9e820089
• https://git.kernel.org/stable/c/8fec16898f184e5f8f8fdd09ff1ced2bd7ffc13d
• https://git.kernel.org/stable/c/5ed1b048527bebe4529eb6e01c34dcc5d97ba5fe
• https://git.kernel.org/stable/c/2aaa41cf974f83a6fb105422bac4e2f107150774