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 2251E2DA74C for ; Mon, 20 Jul 2026 15:15:49 +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=1784560550; cv=none; b=cy4vRqfTLKrUB8ivvTTSYP7Ml0x5FHgq2psSoyeBwqpaBXuO/JXRR8pwKkGqrMUf+9h1m61hV+GuaUa9xccymYspAmYz2hDAVkYEl0Ocd2o7TuQKvzG8ZF+gkl9Ag8ISJM0nbx9+pIrtkGVX1JdfnUFFhyaUv9gDtU15vJOdiCM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784560550; c=relaxed/simple; bh=cc/DmP1hZeJptbbwawuoYEe5ndv9WUely2FlRwTk3Q0=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=C5E3cx0HpeC1+WGdPhUgorsy4fR0sMhpa2sYP5TDBmCLLTJ4Y0GPMiHZBeVM8fSACK36orUgVxzNtbrIeqTwXmGq9m6yCt8DcotQqUCsopSY94xszzEZxjo5GJ41dbgSrKYoBCCKJBVejfE2lIw/OLvfFjm0u8/1tJz2ivRm4iM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UmR0no+n; 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="UmR0no+n" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8969F1F000E9; Mon, 20 Jul 2026 15:15:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784560549; bh=YeMnkef59CblXr8KMMEYL8dhWN0j+Hnv/tRXDkccysg=; h=Subject:To:Cc:From:Date; b=UmR0no+n8P5C9InboU9JAqWEghHFRb/estwxMpe2T312J/JqYLJFcrxJu8n7RrbCX 8IpKQB0I5TJi2IHIL/BGykMTZR0ovqnlu2wL/PE8yll75WZ0aJsdQrDYLADKocXRK7 GW9k/oNX/Bkji06fAr1u9uncR03A7ZH+7ak+fTzo= Subject: FAILED: patch "[PATCH] bpf,fork: wipe ->bpf_storage before bailouts that access it" failed to apply to 5.10-stable tree To: jannh@google.com,andrii@kernel.org Cc: From: Date: Mon, 20 Jul 2026 17:15:30 +0200 Message-ID: <2026072030-external-achiness-22f4@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 9b51a6155d14389876916726430da30eabb1d4ed # git commit -s git send-email --to '' --in-reply-to '2026072030-external-achiness-22f4@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 9b51a6155d14389876916726430da30eabb1d4ed Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Fri, 26 Jun 2026 17:52:52 +0200 Subject: [PATCH] bpf,fork: wipe ->bpf_storage before bailouts that access it Currently, copy_process() can bail out to free_task() before p->bpf_storage has been initialized, with this call graph (shown here for the !CONFIG_MEMCG case): copy_process dup_task_struct arch_dup_task_struct [copies the entire task_struct, including ->bpf_storage member] [RLIMIT_NPROC check fails] delayed_free_task free_task bpf_task_storage_free rcu_dereference(task->bpf_storage) bpf_local_storage_destroy In this case, the nascent task's ->bpf_storage member that bpf_local_storage_destroy() operates on is a plain copy of the parent's ->bpf_storage pointer, not a real initialized pointer. This leads to badness (kernel hangs, UAF). This is reachable as long as the process calling fork() has been inserted into a task storage map. Cc: stable@kernel.org Fixes: a10787e6d58c ("bpf: Enable task local storage for tracing programs") Signed-off-by: Jann Horn Signed-off-by: Andrii Nakryiko diff --git a/kernel/fork.c b/kernel/fork.c index 13e38e89a1f3..f0e2e131a9a5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1009,6 +1009,11 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) tsk->mm_cid.active = 0; INIT_HLIST_NODE(&tsk->mm_cid.node); #endif + +#ifdef CONFIG_BPF_SYSCALL + RCU_INIT_POINTER(tsk->bpf_storage, NULL); + tsk->bpf_ctx = NULL; +#endif return tsk; free_stack: @@ -2247,10 +2252,6 @@ __latent_entropy struct task_struct *copy_process( p->sequential_io = 0; p->sequential_io_avg = 0; #endif -#ifdef CONFIG_BPF_SYSCALL - RCU_INIT_POINTER(p->bpf_storage, NULL); - p->bpf_ctx = NULL; -#endif unwind_task_init(p);