In the Linux kernel, the following vulnerability has been resolved:
PM: hibernate: Fix crash when freeing invalid crypto compressor
When crypto_alloc_acomp() fails, it returns an ERR_PTR value, not NULL. The cleanup code in save_compressed_image() and load_compressed_image()
unconditionally calls crypto_free_acomp() without checking for ERR_PTR,
which causes crypto_acomp_tfm() to dereference an invalid pointer and
crash the kernel. This can be triggered when the compression algorithm is unavailable
(e.g., CONFIG_CRYPTO_LZO not enabled).
Fix by adding IS_ERR_OR_NULL() checks before calling crypto_free_acomp()
and acomp_request_free(), similar to the existing kthread_stop() check.
[ rjw: Added 2 empty code lines ]