From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C90973CFF51 for ; Sun, 18 Oct 2026 15:53:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792338801; cv=none; b=p28az6s+8pSmlwI7Y9yQJd2IDUSFeLXp0DtPDA7g3ev0uXAW3dR4mV/U93ln4pR4FKqiALWVV0hKWLhB2h6CtU3XbqXVMTmtbPg0gBruCvx/QZFo8Wp6R4XIH0wWte2WvmzQL2JxzJa5WH4odUeGuip0wLXEyF1zp2icB2Li3Jk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792338801; c=relaxed/simple; bh=K4gYApPFnbhi0m5+sozprgpxZbZIkmroA77Xs1H0js8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=D3/Cbtll80HxTkBHNs6JbRIybuP36R9MVeGE/n4qZqSyspYfPIlE5glkkMNYxzl3rJLDQZ1tNFsBQkiZe5PBLX8b2yZKnJOTQCfeVTe8EAxg0G4SDzMi2QjOmu4Z0Z8voMq+bWyl31jNVCI05WIfD5rFDOrMZZEQ7Y08vaSMQjU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vEsOgm1Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="vEsOgm1Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 683121F000C4; Sun, 18 Oct 2026 15:53:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792338800; bh=3mQPOKQUVIQU4wmIxlFDjZyOBtcolqOte3oFvnJikSU=; h=From:To:Cc:Subject:Date:Reply-To; b=vEsOgm1ZZVfuW/SwR5vPGnTUD/hMrhNTUltYMedwuFR4Qs5UsEx5smYGwXnRtqUTx nBEngpn08zRwPEOXTQVbZFjTJir06Wi62j8atU+TPa+ZYq+zPzXXr9KtZ1RkISW/RT ryR4Fhp8XbTDkyQLPFFvXTSy8LJZ8UHJ2cIzayG0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98655: perf: Require kernel access for text poke events Date: Sun, 18 Oct 2026 17:43:50 +0200 Message-ID: <2026101849-CVE-2026-98655-b30d@gregkh> X-Mailer: git-send-email 2.56.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3063; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=0BgrqcYY7a1ux44rcpM3jHCRAbnEPSAE71XsQkJJ08U=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlXXppav2SLemtwkeveJr0ZASwrRbYzmy1asMXpLdvim edy+ho3dcSyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBETFczLFjZZ75SxaPg7drt X1ZVda+tuTglSJ1hwZauBScPhdfe99JLC1pl0bz2qP6FqwA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: perf: Require kernel access for text poke events Perf events with exclude_kernel=1 can be opened without kernel perf access. However, exclude_kernel does not suppress text-poke sideband records. Every PERF_RECORD_TEXT_POKE is marked PERF_RECORD_MISC_KERNEL and contains a raw kernel instruction address. An unprivileged task can therefore open and mmap a task-local software event with text_poke=1. Both opening a count-only tracepoint event and configuring UDP GRO for ESP-in-UDP cause updates to inline static calls; the observer receives the relocated addresses of the modified instructions. For a known kernel image, any such address reveals the runtime kernel text base despite KASLR. Call perf_allow_kernel() whenever attr.text_poke is set, regardless of exclude_kernel. Events that neither monitor kernel execution nor request text-poke records retain their existing permissions. The Linux kernel CVE team has assigned CVE-2026-98655 to this issue. Affected and fixed versions =========================== Issue introduced in 5.9 with commit e17d43b93e544f5016c0251d2074c15568d5d963 and fixed in 6.12.113 with commit 8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7 Issue introduced in 5.9 with commit e17d43b93e544f5016c0251d2074c15568d5d963 and fixed in 6.18.56 with commit e506333d1b9f42f1e402acebf1283af3c44a3809 Issue introduced in 5.9 with commit e17d43b93e544f5016c0251d2074c15568d5d963 and fixed in 7.2.10 with commit 677d0b51ac1a0db55d768c4c6399210b3de0795b Issue introduced in 5.9 with commit e17d43b93e544f5016c0251d2074c15568d5d963 and fixed in 7.3-rc6 with commit 357e8a77a501d96c9517f01f4a211eed5e9c9184 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-98655 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: kernel/events/core.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/8473f44db9f710ea6f8cafb22f2e3ba6cb8ca9a7 https://git.kernel.org/stable/c/e506333d1b9f42f1e402acebf1283af3c44a3809 https://git.kernel.org/stable/c/677d0b51ac1a0db55d768c4c6399210b3de0795b https://git.kernel.org/stable/c/357e8a77a501d96c9517f01f4a211eed5e9c9184