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 1D7F73EA970 for ; Sat, 15 Aug 2026 12:29:05 +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=1786796946; cv=none; b=mj9mmY2hKoZpdQR4V2oE9dkiXT//d9FJYQfi1qoJ0vAWTTZ8BassfcFbjFeI7EfrORFKKz58izjolndzc8+Id1Qj0oVre/iHz7Rqao+s7efMtn/We67tGeRbUsIdWeBmIwt/7UMUAnT1mxiuDvIAtuFy1FzQpLF6O5yQ9WSucI8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786796946; c=relaxed/simple; bh=lIPZ3P4xZwjPI0sf7dJEIhTygDFEk9XB86O7uJFtvFg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=u3zfSmLQniJQd3bO6kxsFN3q31Zv9wNNEV7LIzuYupwO6PxWfEQ8rPYaK5WrLWqTJiYK6YTG/VlTofSqaMgP+B5ef0DTB2kMwyLss9b07T5qmDHfcyRngbzR8Y8/ra5Gy0RQVQh1Dkm17AeuIFIkjwghCQC4+fHaLbEOzll9gFg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2Cl7DSpD; 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="2Cl7DSpD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7715E1F000E9; Sat, 15 Aug 2026 12:29:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786796945; bh=n6tREioAmprHRtofHpKvX24H9kKhv5j0w6XUkun3oBo=; h=From:To:Cc:Subject:Date:Reply-To; b=2Cl7DSpDvstkgjb1eperjCMos6B8Xc3pfa1A/x/4dqn/SJBQFgD+yIrP7+6ts15Kj hFCCLfY86Cfepie0eL5w5YYRlIQq5d1uuQCXtzeXAUE6oLIN4R/8Ry7OQQCYqXLoRa RxTcrNBxTOFZAcXAQJTJf3rFO3CMdMiihxYQjYoU= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74477: uprobes: Fix NULL pointer dereference in hprobe_expire() Date: Sat, 15 Aug 2026 21:25:58 +0900 Message-ID: <2026081536-CVE-2026-74477-24c8@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=3183; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=nHUFIfZgUVU/kvH3RUyyQuLGT1IhhzC3IE3zJrzCg9Y=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNUQd6Ged1XdFcti7kbasxg7bjvi8Of7Z82uf64+jiT o9pXUELO2JZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAiTwQYZrMttTntrzJluXXi 9P+TbJaf9NNKvcMwzzqgq6/BWiXh/b3emhm+7c6NVjnqAA== 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: uprobes: Fix NULL pointer dereference in hprobe_expire() Forking a task that has a pending uretprobe can oops the kernel with a NULL pointer dereference in the clone() path: BUG: kernel NULL pointer dereference, address: 0000000000000018 Oops: 0002 [#1] SMP NOPTI RIP: 0010:hprobe_expire CR2: 0000000000000018 Call Trace: uprobe_copy_process copy_process kernel_clone __x64_sys_clone do_syscall_64 entry_SYSCALL_64_after_hwframe This was found on real hosts on Meta fleet. I've got the impression that this is what is happening: CPU 1 CPU 2 (traced task) ----- ------------------- hit uprobe, prepare_uretprobe(): hprobe LEASED, refcount >= 1 uprobe_unregister() put_uprobe(): refcount -> 0 fork() -> dup_utask() hprobe_expire(hprobe, true) try_get_uprobe() -> NULL get_uprobe(NULL) <-- Oops Only take the extra reference when the uprobe is non-NULL; a NULL means it is gone and is the correct value to return. The Linux kernel CVE team has assigned CVE-2026-74477 to this issue. Affected and fixed versions =========================== Issue introduced in 6.13 with commit dd1a7567784e2b1f80258be04f57bcfa82c997eb and fixed in 6.18.44 with commit 3bd35a5e272a1b7a3fb43acad9bdc599281b13fa Issue introduced in 6.13 with commit dd1a7567784e2b1f80258be04f57bcfa82c997eb and fixed in 7.1.8 with commit 06c275a6c0a953ef1d763d11a6891fcc69ae2ac0 Issue introduced in 6.13 with commit dd1a7567784e2b1f80258be04f57bcfa82c997eb and fixed in 7.2-rc6 with commit cc679d7a6303e84d769f2afcde1fc51c51f127cd 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-2026-74477 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/uprobes.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/3bd35a5e272a1b7a3fb43acad9bdc599281b13fa https://git.kernel.org/stable/c/06c275a6c0a953ef1d763d11a6891fcc69ae2ac0 https://git.kernel.org/stable/c/cc679d7a6303e84d769f2afcde1fc51c51f127cd