From nobody Wed Dec 17 12:05:23 2025 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 890FB2248AA; Fri, 21 Mar 2025 12:48:11 +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=1742561291; cv=none; b=JRbi2YStJZJrZWEkvO86RH57OX5Dfq7a5BoetDdx0zGj9jOo26QyJPPNJsbFJjBQVWZrzj4HnMTGtH0GS1+H5gPSDXLCwDKtgd04LtFYzaksPYGFxAenj8z8D0/4XY7hMowvfiKK83szRLH7UmBh2A8MAfR4Ko9T+f0dxUolfV4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742561291; c=relaxed/simple; bh=ulWpz4Aai0sdDwCgU5sVlfrcZ/wicABXdjo+xHGDW0Q=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=kjIMICnB1oe/qkgZ25ePrfA4O1VIPawXKbvZEAP/NTRPpLusbyVqHfgNZHr5i9XIPjFJteCSh44b69clfmvxy/I2RQ2AhZ+2sUWdW9RhmnEonFZxB0uzE9vqHaNbhoiNNh4D4mKmy8PhTLZmGKzWHgiu+rNJlwqLC79VYcqTVGU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PPXH0fGF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PPXH0fGF" Received: by smtp.kernel.org (Postfix) with ESMTPS id 14797C4CEEA; Fri, 21 Mar 2025 12:48:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1742561291; bh=ulWpz4Aai0sdDwCgU5sVlfrcZ/wicABXdjo+xHGDW0Q=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=PPXH0fGFNJRrKIcRrvXzNIdyjAy+uDKaqmJePzwjOPvI0RpSXdrd0fD2RAeDUQ0nX ZkpgrfisYy7DX3HIgRVnQKOP4OiNy5AAeDuQ/M2SYNeLrvyyR7PRUoMkLzBFnS+y72 l9t+MnH/gLDrPN6gPfIa6SXT4p3E8ysIryuM1RbTXHbO3y+hzsRnCgLjfp+NBVxv7z yGAJrtAi2JHyYb82KHNwSyUOLNoUDJSM/JksYTE9V1gG9WWAmZI3Dm2M2kyCwXIIMR LMtOdjBwGOEh4SVJQ7jaDO5XZkSUI7FRUOYZ0eh/n640zeoNwjyIh5Jh8F5JElqnrU BeuM57IHIg/iA== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3F08C36002; Fri, 21 Mar 2025 12:48:10 +0000 (UTC) From: Joel Granados Date: Fri, 21 Mar 2025 13:47:24 +0100 Subject: [PATCH 1/4] sysctl: move u8 register test to lib/test_sysctl.c 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: quoted-printable Message-Id: <20250321-jag-test_extra_val-v1-1-a01b3b17dc66@kernel.org> References: <20250321-jag-test_extra_val-v1-0-a01b3b17dc66@kernel.org> In-Reply-To: <20250321-jag-test_extra_val-v1-0-a01b3b17dc66@kernel.org> To: Kees Cook , Andrew Morton , Shuah Khan , John Sperbeck Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, Joel Granados X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=6197; i=joel.granados@kernel.org; h=from:subject:message-id; bh=ulWpz4Aai0sdDwCgU5sVlfrcZ/wicABXdjo+xHGDW0Q=; b=owJ4nAHtARL+kA0DAAoBupfNUreWQU8ByyZiAGfdYAeU3Wbm3ojUm2x3JxVF90KSyxlJec4Bk VpCsM2UJnu5D4kBswQAAQoAHRYhBK5HCVcl5jElzssnkLqXzVK3lkFPBQJn3WAHAAoJELqXzVK3 lkFPiTQL+gL5vXJ4CNm6vVjLXeVPTKZmkqHccUg2DOlTDHbwEw1fGCwMBkrIxAxsmwTMBve4XbL O81M0V7eJJzKICmKoozJqGidacgfYe3FzF1RzcP/4meWgpKUQaBxd7PCpgQE/BVAwfASjssiCA2 iRj+r6cac3b0WWbaUhh1M9oAM5HIFLrIy0RQuquADP5Ggr3Ff2kxoA3FD8Ho98+8/hSzJf5DaeR cxqiMmm7kc1yhznqsxrU8vQdx0iN1FiZKByoyOvSU/lOkcv46Xy6dh+XesaNciAye/gO+84wl5i iJWwR4NfXtWulPyUmqSaJcNXQ+HR0HJTOc6Omp6tYT4axJJn/JqR9ip0+VFtUaQJiXa2JizLsfC 7Wpuy3etqcW93xn27nXfd1Iwbyh4j9S6zBsoeb0SQPwhMiNKc3rsvGMSgHIVD4bWelSZh4+XP00 5+ZikEWHBfyifCg0YJ8Zs2+nzbtGJpWOhIXRdVzlux1YS1KFuXu+ATh72qzC3hvikn7ZSEWBT26 ls= X-Developer-Key: i=joel.granados@kernel.org; a=openpgp; fpr=F1F8E46D30F0F6C4A45FF4465895FAAC338C6E77 X-Endpoint-Received: by B4 Relay for joel.granados@kernel.org/default with auth_id=239 If the test added in commit b5ffbd139688 ("sysctl: move the extra1/2 boundary check of u8 to sysctl_check_table_array") is run as a module, a lingering reference to the module is left behind, and a 'sysctl -a' leads to a panic. To reproduce CONFIG_KUNIT=3Dy CONFIG_SYSCTL_KUNIT_TEST=3Dm Then run these commands: modprobe sysctl-test rmmod sysctl-test sysctl -a The panic varies but generally looks something like this: BUG: unable to handle page fault for address: ffffa4571c0c7db4 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 100000067 P4D 100000067 PUD 100351067 PMD 114f5e067 PTE 0 Oops: Oops: 0000 [#1] SMP NOPTI ... ... ... RIP: 0010:proc_sys_readdir+0x166/0x2c0 ... ... ... Call Trace: iterate_dir+0x6e/0x140 __se_sys_getdents+0x6e/0x100 do_syscall_64+0x70/0x150 entry_SYSCALL_64_after_hwframe+0x76/0x7e Move the test to lib/test_sysctl.c where the registration reference is handled on module exit 'Fixes: b5ffbd139688 ("sysctl: move the extra1/2 boundary check of u8 to sysctl_check_table_array")' Signed-off-by: Joel Granados Reviewed-by: Kees Cook --- kernel/sysctl-test.c | 49 -------------------------------------- lib/test_sysctl.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++= ++++ 2 files changed, 66 insertions(+), 49 deletions(-) diff --git a/kernel/sysctl-test.c b/kernel/sysctl-test.c index eb2842bd055771ee8a72040f96260bdb0e754ad5..92f94ea28957f48893b0d0d947d= 73001428fecc7 100644 --- a/kernel/sysctl-test.c +++ b/kernel/sysctl-test.c @@ -367,54 +367,6 @@ static void sysctl_test_api_dointvec_write_single_grea= ter_int_max( KUNIT_EXPECT_EQ(test, 0, *((int *)table.data)); } =20 -/* - * Test that registering an invalid extra value is not allowed. - */ -static void sysctl_test_register_sysctl_sz_invalid_extra_value( - struct kunit *test) -{ - unsigned char data =3D 0; - const struct ctl_table table_foo[] =3D { - { - .procname =3D "foo", - .data =3D &data, - .maxlen =3D sizeof(u8), - .mode =3D 0644, - .proc_handler =3D proc_dou8vec_minmax, - .extra1 =3D SYSCTL_FOUR, - .extra2 =3D SYSCTL_ONE_THOUSAND, - }, - }; - - const struct ctl_table table_bar[] =3D { - { - .procname =3D "bar", - .data =3D &data, - .maxlen =3D sizeof(u8), - .mode =3D 0644, - .proc_handler =3D proc_dou8vec_minmax, - .extra1 =3D SYSCTL_NEG_ONE, - .extra2 =3D SYSCTL_ONE_HUNDRED, - }, - }; - - const struct ctl_table table_qux[] =3D { - { - .procname =3D "qux", - .data =3D &data, - .maxlen =3D sizeof(u8), - .mode =3D 0644, - .proc_handler =3D proc_dou8vec_minmax, - .extra1 =3D SYSCTL_ZERO, - .extra2 =3D SYSCTL_TWO_HUNDRED, - }, - }; - - KUNIT_EXPECT_NULL(test, register_sysctl("foo", table_foo)); - KUNIT_EXPECT_NULL(test, register_sysctl("foo", table_bar)); - KUNIT_EXPECT_NOT_NULL(test, register_sysctl("foo", table_qux)); -} - static struct kunit_case sysctl_test_cases[] =3D { KUNIT_CASE(sysctl_test_api_dointvec_null_tbl_data), KUNIT_CASE(sysctl_test_api_dointvec_table_maxlen_unset), @@ -426,7 +378,6 @@ static struct kunit_case sysctl_test_cases[] =3D { KUNIT_CASE(sysctl_test_dointvec_write_happy_single_negative), KUNIT_CASE(sysctl_test_api_dointvec_write_single_less_int_min), KUNIT_CASE(sysctl_test_api_dointvec_write_single_greater_int_max), - KUNIT_CASE(sysctl_test_register_sysctl_sz_invalid_extra_value), {} }; =20 diff --git a/lib/test_sysctl.c b/lib/test_sysctl.c index 4249e0cc8aaff79d7da03aff81b3f9990e9eaac1..54a22e4b134677e022af05df3c7= 5268e7a4a79e7 100644 --- a/lib/test_sysctl.c +++ b/lib/test_sysctl.c @@ -37,6 +37,7 @@ static struct { struct ctl_table_header *test_h_mnterror; struct ctl_table_header *empty_add; struct ctl_table_header *empty; + struct ctl_table_header *test_u8; } sysctl_test_headers; =20 struct test_sysctl_data { @@ -239,6 +240,65 @@ static int test_sysctl_run_register_empty(void) return 0; } =20 +static const struct ctl_table table_u8_over[] =3D { + { + .procname =3D "u8_over", + .data =3D &test_data.uint_0001, + .maxlen =3D sizeof(u8), + .mode =3D 0644, + .proc_handler =3D proc_dou8vec_minmax, + .extra1 =3D SYSCTL_FOUR, + .extra2 =3D SYSCTL_ONE_THOUSAND, + }, +}; + +static const struct ctl_table table_u8_under[] =3D { + { + .procname =3D "u8_under", + .data =3D &test_data.uint_0001, + .maxlen =3D sizeof(u8), + .mode =3D 0644, + .proc_handler =3D proc_dou8vec_minmax, + .extra1 =3D SYSCTL_NEG_ONE, + .extra2 =3D SYSCTL_ONE_HUNDRED, + }, +}; + +static const struct ctl_table table_u8_valid[] =3D { + { + .procname =3D "u8_valid", + .data =3D &test_data.uint_0001, + .maxlen =3D sizeof(u8), + .mode =3D 0644, + .proc_handler =3D proc_dou8vec_minmax, + .extra1 =3D SYSCTL_ZERO, + .extra2 =3D SYSCTL_TWO_HUNDRED, + }, +}; + +static int test_sysctl_register_u8_extra(void) +{ + /* should fail because it's over */ + sysctl_test_headers.test_u8 + =3D register_sysctl("debug/test_sysctl", table_u8_over); + if (sysctl_test_headers.test_u8) + return -ENOMEM; + + /* should fail because it's under */ + sysctl_test_headers.test_u8 + =3D register_sysctl("debug/test_sysctl", table_u8_under); + if (sysctl_test_headers.test_u8) + return -ENOMEM; + + /* should not fail because it's valid */ + sysctl_test_headers.test_u8 + =3D register_sysctl("debug/test_sysctl", table_u8_valid); + if (!sysctl_test_headers.test_u8) + return -ENOMEM; + + return 0; +} + static int __init test_sysctl_init(void) { int err; @@ -256,6 +316,10 @@ static int __init test_sysctl_init(void) goto out; =20 err =3D test_sysctl_run_register_empty(); + if (err) + goto out; + + err =3D test_sysctl_register_u8_extra(); =20 out: return err; @@ -275,6 +339,8 @@ static void __exit test_sysctl_exit(void) unregister_sysctl_table(sysctl_test_headers.empty); if (sysctl_test_headers.empty_add) unregister_sysctl_table(sysctl_test_headers.empty_add); + if (sysctl_test_headers.test_u8) + unregister_sysctl_table(sysctl_test_headers.test_u8); } =20 module_exit(test_sysctl_exit); --=20 2.47.2