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 7A2491C8FBD; Tue, 27 Aug 2024 14:59:45 +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=1724770785; cv=none; b=TrUqYY2pKinwpU+b7XCQ5Jwa7/rSYFsOC57QO0VWUqLmlg6Cyl67uIj+x6rA1LvXU1QEt5PNR5AWxLP4UVfiS19cQN0ozQmE8f0xs8+9rySTkuLlP4JFOAPwM2UEv+z5SaNKXS+tyeRAnglYApUxkWhM04xu/ku8+DQViTBw4eo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724770785; c=relaxed/simple; bh=/OUrT9Wdn2UOUE8T2NWO+ZOwsAGyhy04axXk+pF1XZc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=m+okdpdKpOwwLzpm5uvLHvKHZNa9N2aqRV0l06m7w5uH1Sms9lMkdHQzj1xf5seuD1xvDEmW3fkxUIhUOXYtsmWoPecrUU0HiBRh2NDytDawlaQv/hWoenlBj+J3nHWCyEXBJSBJmv8NVhnPzJSUTTP0yf2Iy12fI2KuDmuoL1g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=v0uXkrDL; 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="v0uXkrDL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B008FC4AF5F; Tue, 27 Aug 2024 14:59:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1724770785; bh=/OUrT9Wdn2UOUE8T2NWO+ZOwsAGyhy04axXk+pF1XZc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v0uXkrDLQQ7jitwLi3rBHRmJCZtY9sxGF54CE/CMgMLTXy9YYGoPjAXXv95Hnp1fi ayqIx1RvPu1YbViEJyrh+rG6SRFF4Dnga59Na7gK8Hcv23YY63rANr1X3w6ptUK6NJ gGmf28589AGoz+ax0LbmbE7NgPJysRMKYC81dIMo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yonghong Song , Alexei Starovoitov , Shung-Hsi Yu Subject: [PATCH 6.6 334/341] selftests/bpf: Add a test to verify previous stacksafe() fix Date: Tue, 27 Aug 2024 16:39:25 +0200 Message-ID: <20240827143856.104495082@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240827143843.399359062@linuxfoundation.org> References: <20240827143843.399359062@linuxfoundation.org> User-Agent: quilt/0.67 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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yonghong Song commit 662c3e2db00f92e50c26e9dc4fe47c52223d9982 upstream. A selftest is added such that without the previous patch, a crash can happen. With the previous patch, the test can run successfully. The new test is written in a way which mimics original crash case: main_prog static_prog_1 static_prog_2 where static_prog_1 has different paths to static_prog_2 and some path has stack allocated and some other path does not. A stacksafe() checking in static_prog_2() triggered the crash. Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20240812214852.214037-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov Signed-off-by: Shung-Hsi Yu Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/bpf/progs/iters.c | 54 ++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) --- a/tools/testing/selftests/bpf/progs/iters.c +++ b/tools/testing/selftests/bpf/progs/iters.c @@ -1411,4 +1411,58 @@ __naked int checkpoint_states_deletion(v ); } +__u32 upper, select_n, result; +__u64 global; + +static __noinline bool nest_2(char *str) +{ + /* some insns (including branch insns) to ensure stacksafe() is triggered + * in nest_2(). This way, stacksafe() can compare frame associated with nest_1(). + */ + if (str[0] == 't') + return true; + if (str[1] == 'e') + return true; + if (str[2] == 's') + return true; + if (str[3] == 't') + return true; + return false; +} + +static __noinline bool nest_1(int n) +{ + /* case 0: allocate stack, case 1: no allocate stack */ + switch (n) { + case 0: { + char comm[16]; + + if (bpf_get_current_comm(comm, 16)) + return false; + return nest_2(comm); + } + case 1: + return nest_2((char *)&global); + default: + return false; + } +} + +SEC("raw_tp") +__success +int iter_subprog_check_stacksafe(const void *ctx) +{ + long i; + + bpf_for(i, 0, upper) { + if (!nest_1(select_n)) { + result = 1; + return 0; + } + } + + result = 2; + return 0; +} + char _license[] SEC("license") = "GPL";