lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 13 May 2022 16:24:08 +0200 From: Greg Kroah-Hartman <gregkh@...uxfoundation.org> To: linux-kernel@...r.kernel.org Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>, stable@...r.kernel.org, Muchun Song <songmuchun@...edance.com>, Axel Rasmussen <axelrasmussen@...gle.com>, David Rientjes <rientjes@...gle.com>, Fam Zheng <fam.zheng@...edance.com>, "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>, Lars Persson <lars.persson@...s.com>, Mike Kravetz <mike.kravetz@...cle.com>, Peter Xu <peterx@...hat.com>, Xiongchun Duan <duanxiongchun@...edance.com>, Zi Yan <ziy@...dia.com>, Andrew Morton <akpm@...ux-foundation.org>, Linus Torvalds <torvalds@...ux-foundation.org> Subject: [PATCH 5.17 08/12] mm: userfaultfd: fix missing cache flush in mcopy_atomic_pte() and __mcopy_atomic() From: Muchun Song <songmuchun@...edance.com> commit 7c25a0b89a487878b0691e6524fb5a8827322194 upstream. userfaultfd calls mcopy_atomic_pte() and __mcopy_atomic() which do not do any cache flushing for the target page. Then the target page will be mapped to the user space with a different address (user address), which might have an alias issue with the kernel address used to copy the data from the user to. Fix this by insert flush_dcache_page() after copy_from_user() succeeds. Link: https://lkml.kernel.org/r/20220210123058.79206-7-songmuchun@bytedance.com Fixes: b6ebaedb4cb1 ("userfaultfd: avoid mmap_sem read recursion in mcopy_atomic") Fixes: c1a4de99fada ("userfaultfd: mcopy_atomic|mfill_zeropage: UFFDIO_COPY|UFFDIO_ZEROPAGE preparation") Signed-off-by: Muchun Song <songmuchun@...edance.com> Cc: Axel Rasmussen <axelrasmussen@...gle.com> Cc: David Rientjes <rientjes@...gle.com> Cc: Fam Zheng <fam.zheng@...edance.com> Cc: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com> Cc: Lars Persson <lars.persson@...s.com> Cc: Mike Kravetz <mike.kravetz@...cle.com> Cc: Peter Xu <peterx@...hat.com> Cc: Xiongchun Duan <duanxiongchun@...edance.com> Cc: Zi Yan <ziy@...dia.com> Signed-off-by: Andrew Morton <akpm@...ux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org> --- mm/userfaultfd.c | 3 +++ 1 file changed, 3 insertions(+) --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -153,6 +153,8 @@ static int mcopy_atomic_pte(struct mm_st /* don't free the page */ goto out; } + + flush_dcache_page(page); } else { page = *pagep; *pagep = NULL; @@ -628,6 +630,7 @@ retry: err = -EFAULT; goto out; } + flush_dcache_page(page); goto retry; } else BUG_ON(page);
Powered by blists - more mailing lists