linux-kernel - [PATCH] mm/memory: Pass head page to do_set

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240611141849.2788693-1-abrestic@rivosinc.com>
Date: Tue, 11 Jun 2024 07:18:49 -0700
From: Andrew Bresticker <abrestic@...osinc.com>
To: Andrew Morton <akpm@...ux-foundation.org>,
	David Hildenbrand <david@...hat.com>
Cc: linux-mm@...ck.org,
	linux-kernel@...r.kernel.org,
	Andrew Bresticker <abrestic@...osinc.com>
Subject: [PATCH] mm/memory: Pass head page to do_set_pmd()

The requirement that the head page be passed to do_set_pmd() was added
in commit ef37b2ea08ac ("mm/memory: page_add_file_rmap() ->
folio_add_file_rmap_[pte|pmd]()") and prevents pmd-mapping in the
finish_fault() path if vmf->page is anything but the head page for an
otherwise suitable vma and pmd-sized page. Have finish_fault() pass in
the head page instead.

Fixes: ef37b2ea08ac ("mm/memory: page_add_file_rmap() -> folio_add_file_rmap_[pte|pmd]()")
Signed-off-by: Andrew Bresticker <abrestic@...osinc.com>
---
 mm/memory.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memory.c b/mm/memory.c
index 0f47a533014e..f13b953b507c 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4764,7 +4764,7 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
 
 	if (pmd_none(*vmf->pmd)) {
 		if (PageTransCompound(page)) {
-			ret = do_set_pmd(vmf, page);
+			ret = do_set_pmd(vmf, compound_head(page));
 			if (ret != VM_FAULT_FALLBACK)
 				return ret;
 		}
-- 
2.34.1