The patch titled Subject: mm: swap: correctly use maxpages in swapon syscall to avoid potential deadloop has been added to the -mm mm-new branch. Its filename is mm-swap-correctly-use-maxpages-in-swapon-syscall-to-avoid-potensial-deadloop-fix.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

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

Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new.

Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days

------------------------------------------------------ From: Kemeng Shi shikemeng@huaweicloud.com Subject: mm: swap: correctly use maxpages in swapon syscall to avoid potential deadloop Date: Fri, 18 Jul 2025 14:51:39 +0800

ensure si->pages == si->max - 1 after setup_swap_extents()

Link: https://lkml.kernel.org/r/20250522122554.12209-3-shikemeng@huaweicloud.com Link: https://lkml.kernel.org/r/20250718065139.61989-1-shikemeng@huaweicloud.com Fixes: 661383c6111a ("mm: swap: relaim the cached parts that got scanned") Signed-off-by: Kemeng Shi shikemeng@huaweicloud.com Reviewed-by: Baoquan He bhe@redhat.com Cc: Johannes Weiner hannes@cmpxchg.org Cc: Kairui Song kasong@tencent.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/swapfile.c | 6 ++++++ 1 file changed, 6 insertions(+)

--- a/mm/swapfile.c~mm-swap-correctly-use-maxpages-in-swapon-syscall-to-avoid-potensial-deadloop-fix +++ a/mm/swapfile.c @@ -3357,6 +3357,12 @@ SYSCALL_DEFINE2(swapon, const char __use error = nr_extents; goto bad_swap_unlock_inode; } + if (si->pages != si->max - 1) { + pr_err("swap:%u != (max:%u - 1)\n", si->pages, si->max); + error = -EINVAL; + goto bad_swap_unlock_inode; + } + maxpages = si->max;

/* OK, set up the swap map and apply the bad block list */ _

Patches currently in -mm which might be from shikemeng@huaweicloud.com are

mm-swap-move-nr_swap_pages-counter-decrement-from-folio_alloc_swap-to-swap_range_alloc.patch mm-swap-correctly-use-maxpages-in-swapon-syscall-to-avoid-potensial-deadloop.patch mm-swap-correctly-use-maxpages-in-swapon-syscall-to-avoid-potensial-deadloop-fix.patch mm-swap-fix-potensial-buffer-overflow-in-setup_clusters.patch mm-swap-remove-stale-comment-stale-comment-in-cluster_alloc_swap_entry.patch