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 18B864156F0; Tue, 15 Sep 2026 11:32:06 +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=1789471928; cv=none; b=ZP09+FrXSN+b5dGw47mk8MN3FJM704SyJLHUuuqLbfh7hKIYrNrhzyvsEy1ttgZjAwIpCG8Vc3n86ARuTz3keqwQ80ZnNHwAlYo+zMOBHd8s5g3c7i+QEaMjGi/GqvxxsFRhzsm/lFjsacE6V76rKXExbmuCNuu80PFGyTyOSIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789471928; c=relaxed/simple; bh=k8f7wEWfxKpIfpqM0ZZciT9rU/+Z+B0mDMLnzjQbKbc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=a620qd8sBV8X/35YTiMXjCfQUGQXIYgg+JNIdr6ih6sesic2kGMatAVDKZH41orY81SwT9ReC5vEd9igxjWpLzqJUK7UOks82+qAmaEHbITwJd8QnJhz4Tg8jRkM5Rjh2pIdgjHanNNclypMhPD+67NZWKrYX7Ci7jttSugXf2o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=C4zmLfJv; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="C4zmLfJv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 887861F00893; Tue, 15 Sep 2026 11:31:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789471926; bh=IxmCoZxNvEY3MY1bZ7ewHUS2NdsWvLK1wdW+Bpu3XII=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=C4zmLfJvLb8/XMAlQ0q3DR72O6RIbbpSlqr7mpxZZCXJCOZxs052NdpfsCeWB6jTO sp7ZSYu4dpiFz7qZobKbv0Abd6MgSlwyvtgrq+Q5gxYnbTDPGivrBv40jjmQzLGjRT vrpW8H100OjuekLO+QbwSm4M7Pzv6OLBPqNmMdQXQ9Pvk4HwKHgkGGqx1zr9MQdDkX DH4Qvm5HZpUEMbwwqO5pgKn+CIl2pzB83ZS8OPqmZIf0xHJv0M68Lea7oxkcu2dWSZ yYvMHPI29Nvht7tAvKnNjpHySotS6aewXYvlGWWYpncPxSi676hzekHoKm/yXfnU59 FZU3zcroOoqIA== From: Christian Brauner Date: Tue, 15 Sep 2026 13:30:52 +0200 Subject: [PATCH RFC POC 06/50] arm64: commit fds on syscall exit Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260915-work-fd-reserve-unify-folded-v1-6-4d5217d6b246@kernel.org> References: <20260915-work-fd-reserve-unify-folded-v1-0-4d5217d6b246@kernel.org> In-Reply-To: <20260915-work-fd-reserve-unify-folded-v1-0-4d5217d6b246@kernel.org> To: Linus Torvalds Cc: Alexander Viro , Jann Horn , Jan Kara , Ingo Molnar , Peter Zijlstra , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Oleg Nesterov , linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, Jens Axboe , io-uring@vger.kernel.org, netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-gpio@vger.kernel.org, linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, bpf@vger.kernel.org, David Airlie , virtualization@lists.linux.dev, kvm@vger.kernel.org, kexec@lists.infradead.org, linux-hyperv@vger.kernel.org, "Christian Brauner (Amutable)" X-Mailer: b4 0.17-dev-db0b7 X-Developer-Signature: v=1; a=openpgp-sha256; l=2286; i=brauner@kernel.org; h=from:subject:message-id; bh=k8f7wEWfxKpIfpqM0ZZciT9rU/+Z+B0mDMLnzjQbKbc=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWSt1KnZs3W+lNrE9bX1j9JX3V1/xZvtQk5p++zvYh+2m 2y+/NbBoKOUhUGMi0FWTJHFod0kXG45T8Vmo0wNmDmsTCBDGLg4BWAi8csYGbbp9Kz+NflwSea1 kB+Gs1Oy2DcWpDxrSJl+sK8+M9b2eyTDb3Z/1XKDldKc0bdKrTceZZ30eNPnnY6Zhw+Lb5A7wqf zgAMA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Add TIF_FD_SLOTS to the syscall work bits. el0_svc_common() rereads the flags after the system call and takes the trace exit for any of them. So a task that reserved descriptors ends up in syscall_trace_exit() which commits them before audit and the ptrace exit stop. Signed-off-by: Christian Brauner (Amutable) --- arch/arm64/include/asm/thread_info.h | 4 +++- arch/arm64/kernel/ptrace.c | 4 ++++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 5d7fe3e153c8..e48006eb98a8 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -74,6 +74,7 @@ void arch_setup_new_exec(void); #define TIF_SECCOMP 11 /* syscall secure computing */ #define TIF_SYSCALL_EMU 12 /* syscall emulation active */ #define TIF_PATCH_PENDING 13 /* pending live patching update */ +#define TIF_FD_SLOTS 14 /* syscall prepared descriptors */ #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ #define TIF_FREEZE 19 #define TIF_RESTORE_SIGMASK 20 @@ -107,10 +108,11 @@ void arch_setup_new_exec(void); #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) #define _TIF_TSC_SIGSEGV (1 << TIF_TSC_SIGSEGV) +#define _TIF_FD_SLOTS (1 << TIF_FD_SLOTS) #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ - _TIF_SYSCALL_EMU) + _TIF_SYSCALL_EMU | _TIF_FD_SLOTS) #ifdef CONFIG_SHADOW_CALL_STACK #define INIT_SCS \ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index f743cbec1c3a..3bedfed977d4 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -2486,6 +2487,9 @@ void syscall_trace_exit(struct pt_regs *regs) { unsigned long flags = read_thread_flags(); + if (flags & _TIF_FD_SLOTS) + fd_slots_commit(regs); + audit_syscall_exit(regs); if (flags & _TIF_SYSCALL_TRACEPOINT) -- 2.53.0