+ mm-set-p-zeromap-to-null-after-freeing-it.patch added to mm-unstable branch

+ mm-set-p-zeromap-to-null-after-freeing-it.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: set p->zeromap to NULL after freeing it
has been added to the -mm mm-unstable branch.  Its filename is
     mm-set-p-zeromap-to-null-after-freeing-it.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-set-p-zeromap-to-null-after-freeing-it.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Usama Arif <usamaarif642@gmail.com>
Subject: mm: set p->zeromap to NULL after freeing it
Date: Wed Jul 10 18:37:57 2024 +0100

alloc_swap_info can reuse swap_info_struct from previously used swap. 
Reset p->zeromap to NULL so that its not set to a corrupted pointer from
previous swap.

Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202407101031.c6c3c651-lkp@intel.com
Cc: Hugh Dickins <hughd@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swapfile.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/swapfile.c~mm-set-p-zeromap-to-null-after-freeing-it
+++ a/mm/swapfile.c
@@ -2654,6 +2654,7 @@ SYSCALL_DEFINE1(swapoff, const char __us
 	p->cluster_next_cpu = NULL;
 	vfree(swap_map);
 	kvfree(p->zeromap);
+	p->zeromap = NULL;
 	kvfree(cluster_info);
 	/* Destroy swap account information */
 	swap_cgroup_swapoff(p->type);
@@ -3346,6 +3347,7 @@ bad_swap:
 	spin_unlock(&swap_lock);
 	vfree(swap_map);
 	kvfree(p->zeromap);
+	p->zeromap = NULL;
 	kvfree(cluster_info);
 	if (inced_nr_rotate_swap)
 		atomic_dec(&nr_rotate_swap);
_

Patches currently in -mm which might be from usamaarif642@gmail.com are

mm-set-p-zeromap-to-null-after-freeing-it.patch