From a1a52a356ba7c41c7318a893e0aafd9faacca939 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=D0=BD=D0=B0=D0=B1?= Date: Mon, 17 May 2021 18:03:26 +0200 Subject: [PATCH] freebsd/libshare: nfs: don't send SIGHUP to all processes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit pidfile_open() sets *pidptr to -1 if the process currently holding the lock is between pidfile_open() and pidfile_write(), the subsequent kill(mountdpid) would potentially SIGHUP all non-system processes except init: just sleep for half a millisecond and try again in that case Reviewed-by: Don Brady Reviewed-by: Brian Behlendorf Reviewed-by: John Kennedy Signed-off-by: Ahelenia Ziemiańska Closes #12067 --- lib/libshare/os/freebsd/nfs.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/lib/libshare/os/freebsd/nfs.c b/lib/libshare/os/freebsd/nfs.c index 56df3e6664..97092bdc0f 100644 --- a/lib/libshare/os/freebsd/nfs.c +++ b/lib/libshare/os/freebsd/nfs.c @@ -423,9 +423,10 @@ nfs_commit_shares(void) struct pidfh *pfh; pid_t mountdpid; +start: pfh = pidfile_open(_PATH_MOUNTDPID, 0600, &mountdpid); if (pfh != NULL) { - /* Mountd is not running. */ + /* mountd(8) is not running. */ pidfile_remove(pfh); return (SA_OK); } @@ -433,6 +434,11 @@ nfs_commit_shares(void) /* Cannot open pidfile for some reason. */ return (SA_SYSTEM_ERR); } + if (mountdpid == -1) { + /* mountd(8) exists, but didn't write the PID yet */ + usleep(500); + goto start; + } /* We have mountd(8) PID in mountdpid variable. */ kill(mountdpid, SIGHUP); return (SA_OK);