From 7966cf0ebe32c981bfa3db252cb5fc3bb1bf2e77 Mon Sep 17 00:00:00 2001 From: Malaya Kumar Rout Date: Tue, 30 Dec 2025 17:26:13 +0530 Subject: [PATCH] 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. Fixes: b03d542c3c95 ("PM: hibernate: Use crypto_acomp interface") Signed-off-by: Malaya Kumar Rout Cc: 6.15+ # 6.15+ [ rjw: Added 2 empty code lines ] Link: https://patch.msgid.link/20251230115613.64080-1-mrout@redhat.com Signed-off-by: Rafael J. Wysocki --- kernel/power/swap.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 33a186373bef..8050e5182835 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -902,8 +902,11 @@ out_clean: for (thr = 0; thr < nr_threads; thr++) { if (data[thr].thr) kthread_stop(data[thr].thr); - acomp_request_free(data[thr].cr); - crypto_free_acomp(data[thr].cc); + if (data[thr].cr) + acomp_request_free(data[thr].cr); + + if (!IS_ERR_OR_NULL(data[thr].cc)) + crypto_free_acomp(data[thr].cc); } vfree(data); } @@ -1499,8 +1502,11 @@ out_clean: for (thr = 0; thr < nr_threads; thr++) { if (data[thr].thr) kthread_stop(data[thr].thr); - acomp_request_free(data[thr].cr); - crypto_free_acomp(data[thr].cc); + if (data[thr].cr) + acomp_request_free(data[thr].cr); + + if (!IS_ERR_OR_NULL(data[thr].cc)) + crypto_free_acomp(data[thr].cc); } vfree(data); }