Module Name: src
Committed By: riastradh
Date: Sun Aug 5 04:26:10 UTC 2012
Modified Files:
src/sys/kern: sys_descrip.c
Log Message:
Force sys_close not to restart by returning ERESTART.
Print a diagnostic message if we ever get ERESTART out of fd_close
and convert it to EINTR instead.
Even if fd_close fails, it has already closed the file descriptor, so
restarting the system call is a mistake, with dangerous consequences
for multithreaded programs.
Should probably turn the message into a kassert eventually, and maybe
add one deeper in fd_close in order to more easily debug it before
all the data structures are destroyed.
To generate a diff of this commit:
cvs rdiff -u -r1.26 -r1.27 src/sys/kern/sys_descrip.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/sys_descrip.c
diff -u src/sys/kern/sys_descrip.c:1.26 src/sys/kern/sys_descrip.c:1.27
--- src/sys/kern/sys_descrip.c:1.26 Sat Feb 11 23:16:17 2012
+++ src/sys/kern/sys_descrip.c Sun Aug 5 04:26:10 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_descrip.c,v 1.26 2012/02/11 23:16:17 martin Exp $ */
+/* $NetBSD: sys_descrip.c,v 1.27 2012/08/05 04:26:10 riastradh Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -67,7 +67,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_descrip.c,v 1.26 2012/02/11 23:16:17 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_descrip.c,v 1.27 2012/08/05 04:26:10 riastradh Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -479,11 +479,22 @@ sys_close(struct lwp *l, const struct sy
/* {
syscallarg(int) fd;
} */
+ int error;
if (fd_getfile(SCARG(uap, fd)) == NULL) {
return EBADF;
}
- return fd_close(SCARG(uap, fd));
+
+ error = fd_close(SCARG(uap, fd));
+ if (error == ERESTART) {
+#ifdef DIAGNOSTIC
+ printf("pid %d: close returned ERESTART\n",
+ (int)l->l_proc->p_pid);
+#endif
+ error = EINTR;
+ }
+
+ return error;
}
/*
