From owner-dev-commits-src-all@freebsd.org Fri Jan 8 21:31:04 2021 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id E671A4D7566; Fri, 8 Jan 2021 21:31:04 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4DCGVw6CTvz3JT5; Fri, 8 Jan 2021 21:31:04 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id C805121DF; Fri, 8 Jan 2021 21:31:04 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 108LV4WA086025; Fri, 8 Jan 2021 21:31:04 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 108LV4B1086024; Fri, 8 Jan 2021 21:31:04 GMT (envelope-from git) Date: Fri, 8 Jan 2021 21:31:04 GMT Message-Id: <202101082131.108LV4B1086024@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Warner Losh Subject: git: 936440560bde - main - sysctl: implement debug.kdb.panic_str MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: imp X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 936440560bde54050e1ad9daae3b9103e05ad3fc Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 08 Jan 2021 21:31:05 -0000 The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=936440560bde54050e1ad9daae3b9103e05ad3fc commit 936440560bde54050e1ad9daae3b9103e05ad3fc Author: Warner Losh AuthorDate: 2021-01-08 16:34:31 +0000 Commit: Warner Losh CommitDate: 2021-01-08 21:30:28 +0000 sysctl: implement debug.kdb.panic_str This is just like debug.kdb.panic, except the string that's passed in is reported in the panic message. This allows people with automated systems to collect kernel panics over a large fleet of machines to flag panics better. Strings like "Warner look at this hang" or "see JIRA ABC-1234 for details" allow these automated systems to route the forced panic to the appropriate engineers like you can with other types of panics. Other users are likely possible. Relnotes: Yes Sponsored by: Netflix Reviewed by: allanjude (earlier version) Suggestions from review folded in by: 0mp, emaste, lwhsu Differential Revision: https://reviews.freebsd.org/D28041 --- share/man/man7/security.7 | 5 +++-- sys/kern/subr_kdb.c | 20 ++++++++++++++++++++ 2 files changed, 23 insertions(+), 2 deletions(-) diff --git a/share/man/man7/security.7 b/share/man/man7/security.7 index 587df4cb74e5..9ff39c74759c 100644 --- a/share/man/man7/security.7 +++ b/share/man/man7/security.7 @@ -28,7 +28,7 @@ .\" .\" $FreeBSD$ .\" -.Dd November 28, 2020 +.Dd January 8, 2020 .Dt SECURITY 7 .Os .Sh NAME @@ -539,7 +539,8 @@ The kernel debugger may not be entered using the .Va debug.kdb.enter sysctl. A panic or trap cannot be forced using the -.Va debug.kdb.panic +.Va debug.kdb.panic , +.Va debug.kdb.panic_str and other sysctl's. .It Ic 2 Highly secure mode \- same as secure mode, plus disks may not be diff --git a/sys/kern/subr_kdb.c b/sys/kern/subr_kdb.c index 576635e4a8dc..9de2d9de13e8 100644 --- a/sys/kern/subr_kdb.c +++ b/sys/kern/subr_kdb.c @@ -82,6 +82,7 @@ static int kdb_sysctl_available(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_current(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_enter(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_panic(SYSCTL_HANDLER_ARGS); +static int kdb_sysctl_panic_str(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_trap(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_trap_code(SYSCTL_HANDLER_ARGS); static int kdb_sysctl_stack_overflow(SYSCTL_HANDLER_ARGS); @@ -109,6 +110,11 @@ SYSCTL_PROC(_debug_kdb, OID_AUTO, panic, kdb_sysctl_panic, "I", "set to panic the kernel"); +SYSCTL_PROC(_debug_kdb, OID_AUTO, panic_str, + CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE, NULL, 0, + kdb_sysctl_panic_str, "A", + "set to panic the kernel with using the string as the panic message"); + SYSCTL_PROC(_debug_kdb, OID_AUTO, trap, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE, NULL, 0, kdb_sysctl_trap, "I", @@ -206,6 +212,20 @@ kdb_sysctl_panic(SYSCTL_HANDLER_ARGS) return (0); } +static int +kdb_sysctl_panic_str(SYSCTL_HANDLER_ARGS) +{ + int error; + static char buf[256]; /* static buffer to limit mallocs when panicing */ + + *buf = '\0'; + error = sysctl_handle_string(oidp, buf, sizeof(buf), req); + if (error != 0 || req->newptr == NULL) + return (error); + panic("kdb_sysctl_panic: %s", buf); + return (0); +} + static int kdb_sysctl_trap(SYSCTL_HANDLER_ARGS) {