From 43b6e31f39edbe7de4f4feeef4d0cf6be093e021 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Mon, 23 Nov 2020 17:12:27 +0100
Subject: [PATCH] quotaio_xfs: Warn when large kernel timestamps cannot be
 handled
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When time_t is 32-bit, warn if the kernel returns anything that cannot
fit in these time stamps. This also fixes a compilation warning that
shift exceeds data type size. Similarly when converting data to pass to
kernel, just avoid the pointless shift (generating compiler warning)
when time_t is 32-bit.

Reported-by: "Dmitry V. Levin" <ldv@altlinux.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 configure.ac  | 2 ++
 quotaio_xfs.c | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/configure.ac b/configure.ac
index 2239b49..296b77a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -82,6 +82,8 @@ AS_IF([test x"$enable_werror" != "xno"], [
 ])
 AC_SUBST([WARN_CFLAGS])
 
+AC_CHECK_SIZEOF([time_t], [], [#include <time.h>])
+
 # =========
 # Find ldap
 # =========
diff --git a/quotaio_xfs.c b/quotaio_xfs.c
index 2db1c0c..5abb2c2 100644
--- a/quotaio_xfs.c
+++ b/quotaio_xfs.c
@@ -45,8 +45,13 @@ report:		xfs_report
 static inline time_t xfs_kern2utildqblk_ts(const struct xfs_kern_dqblk *k,
 		__s32 timer, __s8 timer_hi)
 {
+#if SIZEOF_TIME_T > 4
 	if (k->d_fieldmask & FS_DQ_BIGTIME)
 		return (__u32)timer | (__s64)timer_hi << 32;
+#else
+	if (k->d_fieldmask & FS_DQ_BIGTIME && timer_hi != 0)
+		errstr(_("Truncating kernel returned time stamp."));
+#endif
 	return timer;
 }
 
@@ -54,10 +59,14 @@ static inline void xfs_util2kerndqblk_ts(const struct xfs_kern_dqblk *k,
 		__s32 *timer_lo, __s8 *timer_hi, time_t timer)
 {
 	*timer_lo = timer;
+#if SIZEOF_TIME_T > 4
 	if (k->d_fieldmask & FS_DQ_BIGTIME)
 		*timer_hi = timer >> 32;
 	else
 		*timer_hi = 0;
+#else
+	*timer_hi = 0;
+#endif
 }
 
 static inline int want_bigtime(time_t timer)
-- 
2.26.2