From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B191C38A2D for ; Wed, 26 Oct 2022 15:04:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234058AbiJZPEy (ORCPT ); Wed, 26 Oct 2022 11:04:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233725AbiJZPEw (ORCPT ); Wed, 26 Oct 2022 11:04:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7078550A4 for ; Wed, 26 Oct 2022 08:04:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 627A561F69 for ; Wed, 26 Oct 2022 15:04:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72194C433C1; Wed, 26 Oct 2022 15:04:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666796689; bh=9rXumhiptuTBWc+qxPeMCt8qTQqERXCa2mlDGMdqMpk=; h=Subject:To:Cc:From:Date:From; b=r+GCLPBACmXMrtCD8RlFibOhDnTw0oVNTAiBkyspc8h1a82EI0bYzmBBDQt4EtWZR ARMiw4uHw2EVT5l3e5VaKJTwBYzDIlm1AitNKL5G6VppBBQYsCrrgPDicOsVzuhZXS X+6YHE7aJ42OQL6R59bKFYvo/l+uSvI5VRdInRh0= Subject: FAILED: patch "[PATCH] selinux: enable use of both GFP_KERNEL and GFP_ATOMIC in" failed to apply to 5.4-stable tree To: gongruiqi1@huawei.com, omosnace@redhat.com, paul@paul-moore.com, tanninghao1@huawei.com Cc: From: Date: Wed, 26 Oct 2022 17:04:47 +0200 Message-ID: <166679668721033@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.4-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 . Possible dependencies: abe3c631447d ("selinux: enable use of both GFP_KERNEL and GFP_ATOMIC in convert_context()") d97bd23c2d7d ("selinux: cache the SID -> context string translation") 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From abe3c631447dcd1ba7af972fe6f054bee6f136fa Mon Sep 17 00:00:00 2001 From: "GONG, Ruiqi" Date: Wed, 19 Oct 2022 10:57:10 +0800 Subject: [PATCH] selinux: enable use of both GFP_KERNEL and GFP_ATOMIC in convert_context() The following warning was triggered on a hardware environment: SELinux: Converting 162 SID table entries... BUG: sleeping function called from invalid context at __might_sleep+0x60/0x74 0x0 in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 5943, name: tar CPU: 7 PID: 5943 Comm: tar Tainted: P O 5.10.0 #1 Call trace: dump_backtrace+0x0/0x1c8 show_stack+0x18/0x28 dump_stack+0xe8/0x15c ___might_sleep+0x168/0x17c __might_sleep+0x60/0x74 __kmalloc_track_caller+0xa0/0x7dc kstrdup+0x54/0xac convert_context+0x48/0x2e4 sidtab_context_to_sid+0x1c4/0x36c security_context_to_sid_core+0x168/0x238 security_context_to_sid_default+0x14/0x24 inode_doinit_use_xattr+0x164/0x1e4 inode_doinit_with_dentry+0x1c0/0x488 selinux_d_instantiate+0x20/0x34 security_d_instantiate+0x70/0xbc d_splice_alias+0x4c/0x3c0 ext4_lookup+0x1d8/0x200 [ext4] __lookup_slow+0x12c/0x1e4 walk_component+0x100/0x200 path_lookupat+0x88/0x118 filename_lookup+0x98/0x130 user_path_at_empty+0x48/0x60 vfs_statx+0x84/0x140 vfs_fstatat+0x20/0x30 __se_sys_newfstatat+0x30/0x74 __arm64_sys_newfstatat+0x1c/0x2c el0_svc_common.constprop.0+0x100/0x184 do_el0_svc+0x1c/0x2c el0_svc+0x20/0x34 el0_sync_handler+0x80/0x17c el0_sync+0x13c/0x140 SELinux: Context system_u:object_r:pssp_rsyslog_log_t:s0:c0 is not valid (left unmapped). It was found that within a critical section of spin_lock_irqsave in sidtab_context_to_sid(), convert_context() (hooked by sidtab_convert_params.func) might cause the process to sleep via allocating memory with GFP_KERNEL, which is problematic. As Ondrej pointed out [1], convert_context()/sidtab_convert_params.func has another caller sidtab_convert_tree(), which is okay with GFP_KERNEL. Therefore, fix this problem by adding a gfp_t argument for convert_context()/sidtab_convert_params.func and pass GFP_KERNEL/_ATOMIC properly in individual callers. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20221018120111.1474581-1-gongruiqi1@huawei.com/ [1] Reported-by: Tan Ninghao Fixes: ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve performance") Signed-off-by: GONG, Ruiqi Reviewed-by: Ondrej Mosnacek [PM: wrap long BUG() output lines, tweak subject line] Signed-off-by: Paul Moore diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index fe5fcf571c56..64a6a37dc36d 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -2022,7 +2022,8 @@ static inline int convert_context_handle_invalid_context( * in `newc'. Verify that the context is valid * under the new policy. */ -static int convert_context(struct context *oldc, struct context *newc, void *p) +static int convert_context(struct context *oldc, struct context *newc, void *p, + gfp_t gfp_flags) { struct convert_context_args *args; struct ocontext *oc; @@ -2036,7 +2037,7 @@ static int convert_context(struct context *oldc, struct context *newc, void *p) args = p; if (oldc->str) { - s = kstrdup(oldc->str, GFP_KERNEL); + s = kstrdup(oldc->str, gfp_flags); if (!s) return -ENOMEM; diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index a54b8652bfb5..db5cce385bf8 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -325,7 +325,7 @@ int sidtab_context_to_sid(struct sidtab *s, struct context *context, } rc = convert->func(context, &dst_convert->context, - convert->args); + convert->args, GFP_ATOMIC); if (rc) { context_destroy(&dst->context); goto out_unlock; @@ -404,7 +404,7 @@ static int sidtab_convert_tree(union sidtab_entry_inner *edst, while (i < SIDTAB_LEAF_ENTRIES && *pos < count) { rc = convert->func(&esrc->ptr_leaf->entries[i].context, &edst->ptr_leaf->entries[i].context, - convert->args); + convert->args, GFP_KERNEL); if (rc) return rc; (*pos)++; diff --git a/security/selinux/ss/sidtab.h b/security/selinux/ss/sidtab.h index 4eff0e49dcb2..9fce0d553fe2 100644 --- a/security/selinux/ss/sidtab.h +++ b/security/selinux/ss/sidtab.h @@ -65,7 +65,7 @@ struct sidtab_isid_entry { }; struct sidtab_convert_params { - int (*func)(struct context *oldc, struct context *newc, void *args); + int (*func)(struct context *oldc, struct context *newc, void *args, gfp_t gfp_flags); void *args; struct sidtab *target; };