From 550c228cb0e833244c7f62e4418916842f95d8f6 Mon Sep 17 00:00:00 2001
From: Pavel Butsykin <pbutsykin@cloudlinux.com>
Date: Wed, 31 Dec 2025 11:46:38 +0400
Subject: [PATCH] mm/zswap: fix error pointer free in zswap_cpu_comp_prepare()

commit 590b13669b813d55844fecd9142c56abd567914d upstream.

crypto_alloc_acomp_node() may return ERR_PTR(), but the fail path checks
only for NULL and can pass an error pointer to crypto_free_acomp().  Use
IS_ERR_OR_NULL() to only free valid acomp instances.

Link: https://lkml.kernel.org/r/20251231074638.2564302-1-pbutsykin@cloudlinux.com
Fixes: 779b9955f643 ("mm: zswap: move allocations during CPU init outside the lock")
Signed-off-by: Pavel Butsykin <pbutsykin@cloudlinux.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 mm/zswap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index 00d51d013757..e15052e1a83c 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -866,7 +866,7 @@ static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
 	return 0;
 
 fail:
-	if (acomp)
+	if (!IS_ERR_OR_NULL(acomp))
 		crypto_free_acomp(acomp);
 	kfree(buffer);
 	return ret;