From cc39d2e41ac089ff2f629f360e16724dced3e2fb Mon Sep 17 00:00:00 2001 From: garga Date: Thu, 7 Jan 2016 10:39:13 +0000 Subject: Make cap_mkdb and services_mkdb file operations sync Similar fix was done for passwd and group operations in r285050. When a temporary file is created and then renamed to replace official file there are no checks to make sure data was written to disk and if a power cycle happens at this time, system can end up with a 0 length file Approved by: bapt MFC after: 1 week Sponsored by: Netgate Differential Revision: https://reviews.freebsd.org/D2982 --- usr.sbin/services_mkdb/services_mkdb.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'usr.sbin') diff --git a/usr.sbin/services_mkdb/services_mkdb.c b/usr.sbin/services_mkdb/services_mkdb.c index a91340e..9ea66de 100644 --- a/usr.sbin/services_mkdb/services_mkdb.c +++ b/usr.sbin/services_mkdb/services_mkdb.c @@ -44,6 +44,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include #include @@ -91,6 +92,8 @@ main(int argc, char *argv[]) size_t cnt = 0; StringList *sl, ***svc; size_t port, proto; + char *dbname_dir; + int dbname_dir_fd = -1; setprogname(argv[0]); @@ -138,7 +141,7 @@ main(int argc, char *argv[]) err(1, "Cannot install exit handler"); (void)snprintf(tname, sizeof(tname), "%s.tmp", dbname); - db = dbopen(tname, O_RDWR | O_CREAT | O_EXCL, + db = dbopen(tname, O_RDWR | O_CREAT | O_EXCL | O_SYNC, (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH), DB_HASH, &hinfo); if (!db) err(1, "Error opening temporary database `%s'", tname); @@ -164,8 +167,21 @@ main(int argc, char *argv[]) if ((db->close)(db)) err(1, "Error closing temporary database `%s'", tname); - if (rename(tname, dbname) == -1) + /* + * Make sure file is safe on disk. To improve performance we will call + * fsync() to the directory where file lies + */ + if (rename(tname, dbname) == -1 || + (dbname_dir = dirname(dbname)) == NULL || + (dbname_dir_fd = open(dbname_dir, O_RDONLY|O_DIRECTORY)) == -1 || + fsync(dbname_dir_fd) != 0) { + if (dbname_dir_fd != -1) + close(dbname_dir_fd); err(1, "Cannot rename `%s' to `%s'", tname, dbname); + } + + if (dbname_dir_fd != -1) + close(dbname_dir_fd); return 0; } -- cgit v1.1