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 AB9823644C7 for ; Sat, 15 Aug 2026 06:16:58 +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=1786774619; cv=none; b=Q9x6g8dchsNr+BbvgxIL5VRlOpp49uby0DB2Wy9qYy+A1GDD2vmJ2M/uT0V52XY9FQZnqPh+KEUwiIjcq9BxAOQU54nPvgd7j1vEHtLS7m3HJNnq1R+waf/yC80taPZPGDGj2NpdITwhiOB+ce5gL0HUPNQb9aTcScHG2g1D168= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786774619; c=relaxed/simple; bh=dSwlzJij3MeXcoHn6a2x4hiH7wjjvx/QS07SG1BQPiQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=lbW4cblAfcqvOUD2I+gVbmgv4ySkNCnKalGrpBcyeVM8K6ad8iZ9Q/vKNqI/uSu3gy/KTzXlY+8ZcK3cCXUO6uuzPBuo/z729t8nr/8nPGygqq/z3MHpY/RRABG8IY+bsJjhj4f2NLHfV7r0k88JkzaeE7dwYYqCX8wgJI8YR+M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OzgpFx6j; 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="OzgpFx6j" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E8E41F000E9; Sat, 15 Aug 2026 06:16:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786774618; bh=DVCurxm5alCa4VaDF91k2XusJMN9Gc3ZVIA0kRqeVCA=; h=From:To:Cc:Subject:Date:Reply-To; b=OzgpFx6j3GXwnBGGBpJSSYiLLBuSpgjhPR2FQrHKSRlJeOxtre65MSMaZj6kqZMBI Omn6boGNbUEFpN7A0Q5A5v2VQUsAN8SxDwqIXXjnwX/gdip4jvognl1uIjpBpMk+Sj 5dSoDSaX540UwRK3eRgBH8au/Ci0BhpsoqHrcgaI= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-72217: SUNRPC: Bound-check xdr_buf_to_bvec() stores before writing Date: Sat, 15 Aug 2026 15:04:56 +0900 Message-ID: <2026081546-CVE-2026-72217-6bfc@gregkh> X-Mailer: git-send-email 2.55.0 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=3301; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=QgU+TDg/dOUuLALR3Q7wEL95xk7PoSwUoT9xLhXVWd4=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNDKf07RdPeT79Z6PRsX9d5m8fOF5eXHxTRyTbw12pO X72HTmejlgWBkEmBlkxRZYv23iO7q84pOhlaHsaZg4rE8gQBi5OAZiIXCzDfJ/mknWRy0O+cp+b +Ff64yXzS+cqHBkWrLwasG/G5dpVrdu+LHa6zK9bfL9bDgA= 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: SUNRPC: Bound-check xdr_buf_to_bvec() stores before writing xdr_buf_to_bvec() writes a bio_vec into the caller's array before testing whether that slot is in range, and the head branch performs the store with no check at all. When the caller's budget is exactly used up, the next store lands one element past the end of the array. The overflow label returns count - 1, which masks the surplus store but cannot undo it. rq_bvec, the array passed by nfsd_vfs_write(), is allocated to exactly rq_maxpages entries with no slack. The OOB store can land in adjacent slab memory; the bv_len and bv_offset fields written there are derived from client-supplied RPC payload sizes. Move the in-range check ahead of the store in the head, page-loop, and tail branches. With the check at the top of each sequence, count is incremented only after a successful store, so the overflow label can return count directly. The Linux kernel CVE team has assigned CVE-2026-72217 to this issue. Affected and fixed versions =========================== Issue introduced in 6.6 with commit 2eb2b93581813b74c7174961126f6ec38eadb5a7 and fixed in 6.6.145 with commit 4a1148f2739d5089c3ca8ae2e9d1053e219ab5df Issue introduced in 6.6 with commit 2eb2b93581813b74c7174961126f6ec38eadb5a7 and fixed in 6.12.97 with commit 6029e711a818bf34d6c4b90cafee24f3afffa110 Issue introduced in 6.6 with commit 2eb2b93581813b74c7174961126f6ec38eadb5a7 and fixed in 6.18.40 with commit 69e18135e2a004a79505451dbef07314ea16e1eb Issue introduced in 6.6 with commit 2eb2b93581813b74c7174961126f6ec38eadb5a7 and fixed in 7.1.5 with commit 98414b42530af65cb984ffc12685096a3b5e179a Issue introduced in 6.6 with commit 2eb2b93581813b74c7174961126f6ec38eadb5a7 and fixed in 7.2-rc1 with commit 42f5b80dda6b86e424054baf1475df686c403d5c 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-2026-72217 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: net/sunrpc/xdr.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/4a1148f2739d5089c3ca8ae2e9d1053e219ab5df https://git.kernel.org/stable/c/6029e711a818bf34d6c4b90cafee24f3afffa110 https://git.kernel.org/stable/c/69e18135e2a004a79505451dbef07314ea16e1eb https://git.kernel.org/stable/c/98414b42530af65cb984ffc12685096a3b5e179a https://git.kernel.org/stable/c/42f5b80dda6b86e424054baf1475df686c403d5c