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 85847217659 for ; Sat, 22 Aug 2026 15:40:30 +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=1787413231; cv=none; b=BOsLKrLQ2MQtkvknCMntBfc0qDEJhoHcjHji3VKvQUJ+bIYnSnRiDMMt9LjI972cNGuGADjhR8x7WCijIVH8MpeiI1t/p2/aaMCmn8thOBZQ7TFwApaRMepHX7qU4eXuXZfHFKIFB9FXAVuRRo8sdjxGU1bxwxyTPyEcmmkQMqs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787413231; c=relaxed/simple; bh=8NIivYipoxvu/FR7Z41k5uvGFAmLvR9ptG5g2TVMAOk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=X048vHdHXrTKSYqjFkg3SmJy+kSiSXQc87ly2fReFvOBF/NbdD0zdOIVWf93z7UZ3uYBB1l3seue/xpodgTSdn87bpSvz7ljospWdfbaGFeK18dJKSgGXiobRivSCRdxdKenVG+zzNH26cbI8t09FZcMZ7Gw//JsGCNGOg7I/VQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=b5G+ZqX+; 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="b5G+ZqX+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 926191F000E9; Sat, 22 Aug 2026 15:40:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787413230; bh=57aIs+n07wRNSuYPCwojIotl4u5sqPnE2MFswKgP8Xk=; h=From:To:Cc:Subject:Date:Reply-To; b=b5G+ZqX+AQCplpPS8rDSIaCuO50yfAoHZCc6akMX70OBGqbpQZeLMCa+olK0cuVvt /+hH9+u/dBUH88WfB6Ei2IVtJ51sUmQzKnYFj4c9Zt0p2U4TDvyNzunoidgry02ZTL jdoz6WPJz5DPl+KAEAGPejaurcW9qpUg3C23HRvc= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74729: soc: aspeed: lpc-snoop: Fix usercopy overflow in snoop_file_read Date: Sat, 22 Aug 2026 17:33:33 +0200 Message-ID: <2026082241-CVE-2026-74729-e31d@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=2877; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=7ilttUELs58w+kIycJimKmVPuTJJIBCfjRN9iMsuzL4=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmdB+4eefZa+/xr00Nb78ds1DFyk7s/eVaLscX89LPr0 6tun/Yx6IhlYRBkYpAVU2T5so3n6P6KQ4pehranYeawMoEMYeDiFICJRF1iWHDdpsslyDq92NOk 3ttdJKOK//GkSwzzU3tWfvn5Yd+OiqQW56bkaT4Ho6bMBwA= 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: soc: aspeed: lpc-snoop: Fix usercopy overflow in snoop_file_read put_fifo_with_discard() acts as both producer and consumer on the kfifo: it calls kfifo_skip() (advances out) and kfifo_put() (advances in) from the IRQ handler without synchronizing with snoop_file_read(), which also consumes via kfifo_to_user(). On SMP systems this concurrent access can leave (in - out) larger than the ring buffer, so __kfifo_to_user()'s clamp to (in - out) is ineffective and kfifo_copy_to_user() can attempt a copy_to_user() past the kmalloc-2k backing store: usercopy: Kernel memory exposure attempt detected from SLUB object 'kmalloc-2k' (offset 0, size 2049)! kernel BUG at mm/usercopy.c! Call trace: usercopy_abort __check_heap_object __check_object_size kfifo_copy_to_user __kfifo_to_user snoop_file_read vfs_read Serialize kfifo access with a per-channel spinlock shared between the IRQ handler (producer) and the file reader (consumer). Annotate @fifo with __guarded_by(&lock) and opt the driver into context analysis so the compiler enforces that all fifo access holds the lock. The Linux kernel CVE team has assigned CVE-2026-74729 to this issue. Affected and fixed versions =========================== Issue introduced in 4.19 with commit 3772e5da445420543b25825ac2b5971f3743f6e8 and fixed in 7.1.9 with commit 131ab677b03349a5ae48da8722ec7075b37ec66e Issue introduced in 4.19 with commit 3772e5da445420543b25825ac2b5971f3743f6e8 and fixed in 7.2 with commit 1acef6d85bfd98bd9dfe1f08bffa397a4dda8a6f 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-2026-74729 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: drivers/soc/aspeed/Makefile drivers/soc/aspeed/aspeed-lpc-snoop.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/131ab677b03349a5ae48da8722ec7075b37ec66e https://git.kernel.org/stable/c/1acef6d85bfd98bd9dfe1f08bffa397a4dda8a6f