From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6E448266F17; Tue, 8 Apr 2025 12:29:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744115378; cv=none; b=DLKuAxGa94M99P/QEDJB20v6J/DA8ow1RJ+oCkKZX7QaJ4DrH76j25wDb9wsQClUnJGsy+LbhDRAtOcW/H5eKDc+YH4jlKcn43r4AvoHp4XbinMR0X5oYFb0tDLKuOHTydxulsVR5LBHZlOsakbkqvHFEnO76KKLyI4QrDhcnt8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744115378; c=relaxed/simple; bh=qYskY8Sm75Y61lX7uOR1Ww0Xv19+OcqWfVtbdxigl+I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qHdu8O+vJbwK71THkIjHBoTi+8vJ+v88gp4Kr9OYo/+BNMQYg9+OHiuT3AUycWWKBWGN5aEksXG5TfqY8ECyyNP/vapQu4V1f6StQG2Sk/qGH/vMJ92Nb3ZyvDUdms64K7mbh2XEo8IJlSd87QaR0nam1IWUa5YgUGd1CUtltgE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KEPGOqw+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="KEPGOqw+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0EEEC4CEE5; Tue, 8 Apr 2025 12:29:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744115378; bh=qYskY8Sm75Y61lX7uOR1Ww0Xv19+OcqWfVtbdxigl+I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KEPGOqw+uf6RvXqtx17DTkY6TzD331lFKv+dp/jNuXSLO+Reqk+mhYijEWqbBph7l z9ZhTS5su3sVb+lVij81wH2zEhEWGPbxURBHHW+5RW9kR69IswSOiif9dF9Bg5SBJA hNL9nmzlVxm1huoorKfmjYzMBY9WkCC8EUFRIork= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jann Horn , Jiri Olsa , Ingo Molnar , Oleg Nesterov , Kees Cook , Andrii Nakryiko , "Masami Hiramatsu (Google)" , Alexei Starovoitov , Andy Lutomirski Subject: [PATCH 6.13 451/499] uprobes/x86: Harden uretprobe syscall trampoline check Date: Tue, 8 Apr 2025 12:51:03 +0200 Message-ID: <20250408104902.479958396@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104851.256868745@linuxfoundation.org> References: <20250408104851.256868745@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Olsa commit fa6192adc32f4fdfe5b74edd5b210e12afd6ecc0 upstream. Jann reported a possible issue when trampoline_check_ip returns address near the bottom of the address space that is allowed to call into the syscall if uretprobes are not set up: https://lore.kernel.org/bpf/202502081235.5A6F352985@keescook/T/#m9d416df341b8fbc11737dacbcd29f0054413cbbf Though the mmap minimum address restrictions will typically prevent creating mappings there, let's make sure uretprobe syscall checks for that. Fixes: ff474a78cef5 ("uprobe: Add uretprobe syscall to speed up return probe") Reported-by: Jann Horn Signed-off-by: Jiri Olsa Signed-off-by: Ingo Molnar Reviewed-by: Oleg Nesterov Reviewed-by: Kees Cook Acked-by: Andrii Nakryiko Acked-by: Masami Hiramatsu (Google) Acked-by: Alexei Starovoitov Cc: Andy Lutomirski Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250212220433.3624297-1-jolsa@kernel.org Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/uprobes.c | 14 +++++++++----- include/linux/uprobes.h | 2 ++ kernel/events/uprobes.c | 2 +- 3 files changed, 12 insertions(+), 6 deletions(-) --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -357,19 +357,23 @@ void *arch_uprobe_trampoline(unsigned lo return &insn; } -static unsigned long trampoline_check_ip(void) +static unsigned long trampoline_check_ip(unsigned long tramp) { - unsigned long tramp = uprobe_get_trampoline_vaddr(); - return tramp + (uretprobe_syscall_check - uretprobe_trampoline_entry); } SYSCALL_DEFINE0(uretprobe) { struct pt_regs *regs = task_pt_regs(current); - unsigned long err, ip, sp, r11_cx_ax[3]; + unsigned long err, ip, sp, r11_cx_ax[3], tramp; + + /* If there's no trampoline, we are called from wrong place. */ + tramp = uprobe_get_trampoline_vaddr(); + if (unlikely(tramp == UPROBE_NO_TRAMPOLINE_VADDR)) + goto sigill; - if (regs->ip != trampoline_check_ip()) + /* Make sure the ip matches the only allowed sys_uretprobe caller. */ + if (unlikely(regs->ip != trampoline_check_ip(tramp))) goto sigill; err = copy_from_user(r11_cx_ax, (void __user *)regs->sp, sizeof(r11_cx_ax)); --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -38,6 +38,8 @@ struct page; #define MAX_URETPROBE_DEPTH 64 +#define UPROBE_NO_TRAMPOLINE_VADDR (~0UL) + struct uprobe_consumer { /* * handler() can return UPROBE_HANDLER_REMOVE to signal the need to --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -2118,8 +2118,8 @@ void uprobe_copy_process(struct task_str */ unsigned long uprobe_get_trampoline_vaddr(void) { + unsigned long trampoline_vaddr = UPROBE_NO_TRAMPOLINE_VADDR; struct xol_area *area; - unsigned long trampoline_vaddr = -1; /* Pairs with xol_add_vma() smp_store_release() */ area = READ_ONCE(current->mm->uprobes_state.xol_area); /* ^^^ */