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Perez de Azpillaga" X-Mailer: b4 0.17-dev-39d60 X-Rspamd-Queue-Id: 9A806180004 X-Stat-Signature: h5asd83q4r6th61oux184dnwkjax3agg X-Rspamd-Server: rspam04 X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793265562-64064 X-HE-Meta: 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 kIzoUPPf UsxJtJO7NOSZHB70EDCuh96QU4Q4dmYm2SbTxZsjy+g0HpLOL1OWFg5LTEzUHzwexlhKfJa/jDW73JomcJGGeHH13WlmP49wwA86achELHMmZMxdxSHj3IpI24TsyHik+SgHNft6cP59nswBBjPQoJNBqpBQogfS2TXI1im21S1tXyW7/E2Uop9ZToSIG3ivW67SAyev068ZRlGZJZ/NpIPbRD6EqCX/kGb5M8t8Er/5XC5BWxERXMVNREEVUZy5eRAmGBD8egpPqmP2EzlUWsQK7vz1v48YJC2LqdQS+ur/Zv0G7RgAY/BIWzMSEezN4sz23G0zvnncTIWu86RAyqq85LL1RdaJ457fJFGH32LH4Vvw= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 remap_vmalloc_range_partial() passes vmalloc_to_page()'s result to vm_insert_page() unchecked, oopsing via page_folio() if the page is NULL. The NULL case never happens today because VM_USERMAP areas keep every page mapped, but that assumption is nowhere checked. Patch 1 drops VM_DMA_COHERENT from the allow-list -- a dead entry (no caller maps a DMA-coherent area through this path). Patch 2 fails the mapping with -EINVAL instead of oopsing if vmalloc_to_page() ever returns NULL, with a WARN to mark the broken invariant. Patch 1 is a behavior change (no in-tree caller affected) Patch 2 only changes a failure path that cannot be reached today. The two are independent. Signed-off-by: Ye Liu --- Changes in v2: - patch 1: drop the vrealloc-shrink justification. - patch 2: fail with -EINVAL rather than oopsing. - Link to v1: https://patch.msgid.link/20261026-vmalloc_remap-v1-0-b7a907814e90@linux.dev --- Ye Liu (2): mm/vmalloc: drop VM_DMA_COHERENT from remap_vmalloc_range_partial mm/vmalloc: reject NULL pages in remap_vmalloc_range_partial mm/vmalloc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- base-commit: 2efb7a11f1aa4d2dc285fe2680cca22cb9f72f64 change-id: 20261026-vmalloc_remap-012cf418c2a8 Best regards, -- Ye Liu