From owner-freebsd-hackers@FreeBSD.ORG Sun Mar 22 11:48:13 2015 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id B2BF7603 for ; Sun, 22 Mar 2015 11:48:13 +0000 (UTC) Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by mx1.freebsd.org (Postfix) with ESMTP id C2C7867D for ; Sun, 22 Mar 2015 11:48:11 +0000 (UTC) Received: from freebsd (unknown [58.211.218.74]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygA3FxT0qw5VcTHDAw--.32466S2; Sun, 22 Mar 2015 19:48:08 +0800 (CST) Date: Sun, 22 Mar 2015 19:47:46 +0800 From: Tiwei Bie To: Mateusz Guzik Subject: Re: [PATCH] Finish the task 'Validate coredump format string' Message-ID: <20150322114746.GA53624@freebsd> References: <1426946345-67889-1-git-send-email-btw@mail.ustc.edu.cn> <20150321200500.GC14650@dft-labs.eu> <20150322091853.GA89976@freebsd> <20150322101401.GH14650@dft-labs.eu> <20150322112555.GA44277@freebsd> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20150322112555.GA44277@freebsd> User-Agent: Mutt/1.5.23 (2014-03-12) X-CM-TRANSID: LkAmygA3FxT0qw5VcTHDAw--.32466S2 X-Coremail-Antispam: 1UD129KBjvJXoWxJw4kJr43ArW8Kr15tF4rGrg_yoW5ury8pF yrCr98ArZYkr43CFn3Z3yrAa4Yy3s5A3yUW343Xw1akryFgry8Xr1rKr1FvF1kGr4vqasx Ja15WFy7Kryjv3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUv2b7Iv0xC_tr1lb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rw A2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xII jxv20xvEc7CjxVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I 8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI 64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVW8JVWxJw Am72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IY64vIr41lc2xSY4AK67AK6r4kMxAIw28IcxkI 7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMxCIbckI1I0E14v26r1Y6r17MI8I3I0E5I 8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUXVWU AwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x 0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_Wr1j6rW3Jr1lIxAIcVC2z280aVAF wI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa 7IU0co7tUUUUU== X-CM-SenderInfo: xewzqzxdloh3xvwfhvlgxou0/1tbiAQUQAVQhl-peFAAMsL Cc: Konstantin Belousov , freebsd-hackers@freebsd.org X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Mar 2015 11:48:13 -0000 On Sun, Mar 22, 2015 at 07:25:55PM +0800, Tiwei Bie wrote: > On Sun, Mar 22, 2015 at 11:14:01AM +0100, Mateusz Guzik wrote: > > On Sun, Mar 22, 2015 at 05:19:40PM +0800, Tiwei Bie wrote: > [..] > > > > A dedicated sysinit func could fetch and validate the tunable, if any. > > If no tunable was provided it would alloc memory for the default. > > > > My new patch, that uses a dedicated sysinit func to fetch and validate > the tunable: > [..] > static int > sysctl_kern_corefile(SYSCTL_HANDLER_ARGS) > { > + char *format; > int error; > > + format = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); > + > + sx_slock(&corefilename_lock); > + strncpy(format, corefilename, MAXPATHLEN); > + sx_sunlock(&corefilename_lock); > + > + error = sysctl_handle_string(oidp, format, MAXPATHLEN, req); > + if (error != 0 || strcmp(format, corefilename) == 0 || > + !corefilename_check(format)) > + goto out; > + > sx_xlock(&corefilename_lock); > error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename), > req); Sorry, I was too hurried. ;-( Fix typo: --- sys/kern/kern_sig.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 60 insertions(+), 3 deletions(-) diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c index 8410d9d..1ade17f 100644 --- a/sys/kern/kern_sig.c +++ b/sys/kern/kern_sig.c @@ -3096,19 +3096,76 @@ static int compress_user_cores = 0; static char corefilename[MAXPATHLEN] = {"%N.core"}; +static bool +corefilename_check(const char *format) +{ + int i, counti; + + counti = 0; + for (i = 0; format[i] != '\0'; i++) { + if (format[i] == '%') { + i++; + switch (format[i]) { + case 'I': + counti++; + if (counti > 1) { + printf("Too many index flags specified " + "in corename `%s'\n", format); + return (false); + } + case '%': + case 'H': + case 'N': + case 'P': + case 'U': + break; + default: + printf("Unknown format character %c in " + "corename `%s'\n", format[i], format); + return (false); + } + } + } + + return (true); +} + +static void +corefilename_init(void *arg) +{ + char *format = kern_getenv("kern.corefile"); + + if (format != NULL && corefilename_check(format)) + strncpy(corefilename, format, sizeof(corefilename)); +} +SYSINIT(corefilename, SI_SUB_KMEM, SI_ORDER_FIRST, corefilename_init, 0); + static int sysctl_kern_corefile(SYSCTL_HANDLER_ARGS) { + char *format; int error; + format = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); + + sx_slock(&corefilename_lock); + strncpy(format, corefilename, MAXPATHLEN); + sx_sunlock(&corefilename_lock); + + error = sysctl_handle_string(oidp, format, MAXPATHLEN, req); + if (error != 0 || strcmp(format, corefilename) == 0 || + !corefilename_check(format)) + goto out; + sx_xlock(&corefilename_lock); - error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename), - req); + strncpy(corefilename, format, sizeof(corefilename)); sx_xunlock(&corefilename_lock); +out: + free(format, M_TEMP); return (error); } -SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RWTUN | +SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A", "Process corefile name format string"); -- 2.1.2 Best regards, Tiwei Bie