The patch titled Subject: fs/proc/task_mmu: prevent integer overflow in pagemap_scan_get_args() has been added to the -mm mm-hotfixes-unstable branch. Its filename is fs-proc-task_mmu-prevent-integer-overflow-in-pagemap_scan_get_args.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-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Dan Carpenter dan.carpenter@linaro.org Subject: fs/proc/task_mmu: prevent integer overflow in pagemap_scan_get_args() Date: Thu, 14 Nov 2024 11:59:32 +0300

The "arg->vec_len" variable is a u64 that comes from the user at the start of the function. The "arg->vec_len * sizeof(struct page_region))" multiplication can lead to integer wrapping. Use size_mul() to avoid that.

Also the size_add/mul() functions work on unsigned long so for 32bit systems we need to ensure that "arg->vec_len" fits in an unsigned long.

Link: https://lkml.kernel.org/r/39d41335-dd4d-48ed-8a7f-402c57d8ea84@stanley.mount... Fixes: 52526ca7fdb9 ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Cc: Andrei Vagin avagin@google.com Cc: Andrii Nakryiko andrii@kernel.org Cc: Arnd Bergmann arnd@arndb.de Cc: David Hildenbrand david@redhat.com Cc: Matthew Wilcox willy@infradead.org Cc: Micha�� Miros��aw mirq-linux@rere.qmqm.pl Cc: Muhammad Usama Anjum usama.anjum@collabora.com Cc: Oscar Salvador osalvador@suse.de Cc: Peter Xu peterx@redhat.com Cc: Ryan Roberts ryan.roberts@arm.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

fs/proc/task_mmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/proc/task_mmu.c~fs-proc-task_mmu-prevent-integer-overflow-in-pagemap_scan_get_args +++ a/fs/proc/task_mmu.c @@ -2665,8 +2665,10 @@ static int pagemap_scan_get_args(struct return -EFAULT; if (!arg->vec && arg->vec_len) return -EINVAL; + if (UINT_MAX == SIZE_MAX && arg->vec_len > SIZE_MAX) + return -EINVAL; if (arg->vec && !access_ok((void __user *)(long)arg->vec, - arg->vec_len * sizeof(struct page_region))) + size_mul(arg->vec_len, sizeof(struct page_region)))) return -EFAULT;

/* Fixup default values */ _

Patches currently in -mm which might be from dan.carpenter@linaro.org are

fs-proc-task_mmu-prevent-integer-overflow-in-pagemap_scan_get_args.patch