From owner-freebsd-hackers@FreeBSD.ORG Thu Mar 19 07:14:16 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 52986A36 for ; Thu, 19 Mar 2015 07:14:16 +0000 (UTC) Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by mx1.freebsd.org (Postfix) with ESMTP id 8A2C0E9 for ; Thu, 19 Mar 2015 07:14:14 +0000 (UTC) Received: from freebsd.my.domain (unknown [58.211.218.74]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygCniBU0dwpV82KxAw--.41360S2; Thu, 19 Mar 2015 15:14:08 +0800 (CST) From: Tiwei Bie To: mjguzik@gmail.com Subject: [PATCH] Finish the task 'Fix corefilename race' Date: Thu, 19 Mar 2015 15:13:43 +0800 Message-Id: <1426749223-18118-1-git-send-email-btw@mail.ustc.edu.cn> X-Mailer: git-send-email 2.3.1 X-CM-TRANSID: LkAmygCniBU0dwpV82KxAw--.41360S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Cr1kXr4fKrWDuw13WrWfXwb_yoW8Cw1DpF 4Fk34rArs3CF43CF1fZFW5CF1Yy348tr4UW3sxXF4Ykr1Fqry8XF1rtryFqF1kWrn2gr98 Ja15Xr9xKrWjq3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkIb7Iv0xC_KF4lb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rw A2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xII jxv20xvEc7CjxVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwV C2z280aVCY1x0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUXVWUAwAv7VC2z280aVAFwI0_Cr0_Gr 1UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwCY02Avz4vE14v_GF4l42xK 82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGw C20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1Y6r17MIIYrxkI7VAKI48J MIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMI IF0xvE42xK8VAvwI8IcIk0rVWrZr1j6s0DMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvE x4A2jsIEc7CjxVAFwI0_Jr0_GrUvcSsGvfC2KfnxnUUI43ZEXa7IU8VT5PUUUUU== X-CM-SenderInfo: xewzqzxdloh3xvwfhvlgxou0/1tbiAQUNAVQhl-l6PQACsW Cc: 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: Thu, 19 Mar 2015 07:14:16 -0000 Hi, Mateusz! I have finished the task: Fix corefilename race [1]. Following is my patch: --- sys/kern/kern_sig.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c index 58d9707..a1421cb 100644 --- a/sys/kern/kern_sig.c +++ b/sys/kern/kern_sig.c @@ -3090,8 +3090,24 @@ static int compress_user_cores = 0; #endif static char corefilename[MAXPATHLEN] = {"%N.core"}; -SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RWTUN, corefilename, - sizeof(corefilename), "Process corefile name format string"); + +static struct sx corefilename_lock; +SX_SYSINIT(corefilename_init, &corefilename_lock, "corefilename lock"); + +static int +sysctl_kern_corefile(SYSCTL_HANDLER_ARGS) +{ + int error; + + sx_xlock(&corefilename_lock); + error = sysctl_handle_string(oidp, corefilename, MAXPATHLEN, req); + sx_xunlock(&corefilename_lock); + + return (error); +} +SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RWTUN | + CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A", + "Process corefile name format string"); /* * corefile_open(comm, uid, pid, td, compress, vpp, namep) @@ -3120,6 +3136,7 @@ corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td, name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO); indexpos = -1; (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN); + sx_slock(&corefilename_lock); for (i = 0; format[i] != '\0'; i++) { switch (format[i]) { case '%': /* Format character */ @@ -3162,6 +3179,7 @@ corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td, break; } } + sx_sunlock(&corefilename_lock); free(hostname, M_TEMP); if (compress) sbuf_printf(&sb, GZ_SUFFIX); -- 2.1.2 [1] https://wiki.freebsd.org/JuniorJobs#Fix_corefilename_race Best regards, Tiwei Bie