Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 395 insertions, 0 deletions

diff --git a/fs/fat/fat_test.c b/fs/fat/fat_test.c
new file mode 100644
index 000000000..9583ce66d
--- /dev/null
+++ b/fs/fat/fat_test.c
@@ -0,0 +1,395 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit tests for FAT filesystems.
+ *
+ * Copyright (C) 2020 Google LLC.
+ * Author: David Gow <davidgow@google.com>
+ */
+
+#include <kunit/test.h>
+
+#include "fat.h"
+
+static void fat_checksum_test(struct kunit *test)
+{
+	/* With no extension. */
+	KUNIT_EXPECT_EQ(test, fat_checksum("VMLINUX    "), (u8)44);
+	/* With 3-letter extension. */
+	KUNIT_EXPECT_EQ(test, fat_checksum("README  TXT"), (u8)115);
+	/* With short (1-letter) extension. */
+	KUNIT_EXPECT_EQ(test, fat_checksum("ABCDEFGHA  "), (u8)98);
+}
+
+static void fat_clus_to_blknr_test(struct kunit *test)
+{
+	static const struct msdos_sb_info sbi = {
+		.sec_per_clus = 4,
+		.data_start = 100,
+	};
+
+	KUNIT_EXPECT_EQ(test, (sector_t)100,
+			fat_clus_to_blknr(&sbi, FAT_START_ENT));
+	KUNIT_EXPECT_EQ(test, (sector_t)112, fat_clus_to_blknr(&sbi, 5));
+}
+
+static void fat_get_blknr_offset_test(struct kunit *test)
+{
+	static const struct msdos_sb_info sbi = {
+		.dir_per_block = 16,
+		.dir_per_block_bits = 4,
+	};
+
+	sector_t blknr;
+	int offset;
+
+	fat_get_blknr_offset(&sbi, 0, &blknr, &offset);
+	KUNIT_EXPECT_EQ(test, (sector_t)0, blknr);
+	KUNIT_EXPECT_EQ(test, 0, offset);
+
+	fat_get_blknr_offset(&sbi, (10 << 4) | 7, &blknr, &offset);
+	KUNIT_EXPECT_EQ(test, (sector_t)10, blknr);
+	KUNIT_EXPECT_EQ(test, 7, offset);
+}
+
+struct fat_timestamp_testcase {
+	const char *name;
+	struct timespec64 ts;
+	__le16 time;
+	__le16 date;
+	u8 cs;
+	int time_offset;
+};
+
+struct fat_unix2fat_clamp_testcase {
+	const char *name;
+	struct timespec64 ts;
+	__le16 time;
+	__le16 date;
+	u8 cs;
+	int time_offset;
+};
+
+struct fat_truncate_atime_testcase {
+	const char *name;
+	struct timespec64 ts;
+	struct timespec64 expected;
+	int time_offset;
+};
+
+static struct fat_timestamp_testcase time_test_cases[] = {
+	{
+		.name = "Earliest possible UTC (1980-01-01 00:00:00)",
+		.ts = {.tv_sec = 315532800LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(33),
+		.cs = 0,
+		.time_offset = 0,
+	},
+	{
+		.name = "Latest possible UTC (2107-12-31 23:59:58)",
+		.ts = {.tv_sec = 4354819198LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(49021),
+		.date = cpu_to_le16(65439),
+		.cs = 0,
+		.time_offset = 0,
+	},
+	{
+		.name = "Earliest possible (UTC-11) (== 1979-12-31 13:00:00 UTC)",
+		.ts = {.tv_sec = 315493200LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(33),
+		.cs = 0,
+		.time_offset = 11 * 60,
+	},
+	{
+		.name = "Latest possible (UTC+11) (== 2108-01-01 10:59:58 UTC)",
+		.ts = {.tv_sec = 4354858798LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(49021),
+		.date = cpu_to_le16(65439),
+		.cs = 0,
+		.time_offset = -11 * 60,
+	},
+	{
+		.name = "Leap Day / Year (1996-02-29 00:00:00)",
+		.ts = {.tv_sec = 825552000LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(8285),
+		.cs = 0,
+		.time_offset = 0,
+	},
+	{
+		.name = "Year 2000 is leap year (2000-02-29 00:00:00)",
+		.ts = {.tv_sec = 951782400LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(10333),
+		.cs = 0,
+		.time_offset = 0,
+	},
+	{
+		.name = "Year 2100 not leap year (2100-03-01 00:00:00)",
+		.ts = {.tv_sec = 4107542400LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(61537),
+		.cs = 0,
+		.time_offset = 0,
+	},
+	{
+		.name = "Leap year + timezone UTC+1 (== 2004-02-29 00:30:00 UTC)",
+		.ts = {.tv_sec = 1078014600LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(48064),
+		.date = cpu_to_le16(12380),
+		.cs = 0,
+		.time_offset = -60,
+	},
+	{
+		.name = "Leap year + timezone UTC-1 (== 2004-02-29 23:30:00 UTC)",
+		.ts = {.tv_sec = 1078097400LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(960),
+		.date = cpu_to_le16(12385),
+		.cs = 0,
+		.time_offset = 60,
+	},
+	{
+		.name = "VFAT odd-second resolution (1999-12-31 23:59:59)",
+		.ts = {.tv_sec = 946684799LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(49021),
+		.date = cpu_to_le16(10143),
+		.cs = 100,
+		.time_offset = 0,
+	},
+	{
+		.name = "VFAT 10ms resolution (1980-01-01 00:00:00:0010)",
+		.ts = {.tv_sec = 315532800LL, .tv_nsec = 10000000L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(33),
+		.cs = 1,
+		.time_offset = 0,
+	},
+};
+
+static struct fat_unix2fat_clamp_testcase unix2fat_clamp_test_cases[] = {
+	{
+		.name = "Clamp to earliest FAT date for 1979-12-31 23:59:59 UTC",
+		.ts = {.tv_sec = 315532799LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(33),
+		.cs = 0,
+		.time_offset = 0,
+	},
+	{
+		.name = "Clamp after time_offset=-60 pushes 1980-01-01 00:30 UTC below 1980",
+		.ts = {.tv_sec = 315534600LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(0),
+		.date = cpu_to_le16(33),
+		.cs = 0,
+		.time_offset = -60,
+	},
+	{
+		.name = "Clamp to latest FAT date for 2108-01-01 00:00:00 UTC",
+		.ts = {.tv_sec = 4354819200LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(49021),
+		.date = cpu_to_le16(65439),
+		.cs = 199,
+		.time_offset = 0,
+	},
+	{
+		.name = "Clamp after time_offset=60 pushes 2107-12-31 23:30 UTC beyond 2107",
+		.ts = {.tv_sec = 4354817400LL, .tv_nsec = 0L},
+		.time = cpu_to_le16(49021),
+		.date = cpu_to_le16(65439),
+		.cs = 199,
+		.time_offset = 60,
+	},
+};
+
+static struct fat_truncate_atime_testcase truncate_atime_test_cases[] = {
+	{
+		.name = "UTC atime truncates to 2004-02-29 00:00:00",
+		.ts = {.tv_sec = 1078058096LL, .tv_nsec = 789000000L},
+		.expected = {.tv_sec = 1078012800LL, .tv_nsec = 0L},
+		.time_offset = 0,
+	},
+	{
+		.name = "time_offset=-60 truncates 2004-02-29 00:30 UTC to previous local midnight",
+		.ts = {.tv_sec = 1078014645LL, .tv_nsec = 123000000L},
+		.expected = {.tv_sec = 1077930000LL, .tv_nsec = 0L},
+		.time_offset = -60,
+	},
+	{
+		.name = "time_offset=60 truncates 2004-02-29 23:30 UTC to next local midnight",
+		.ts = {.tv_sec = 1078097445LL, .tv_nsec = 123000000L},
+		.expected = {.tv_sec = 1078095600LL, .tv_nsec = 0L},
+		.time_offset = 60,
+	},
+};
+
+static void time_testcase_desc(struct fat_timestamp_testcase *t,
+			       char *desc)
+{
+	strscpy(desc, t->name, KUNIT_PARAM_DESC_SIZE);
+}
+
+static void unix2fat_clamp_testcase_desc(struct fat_unix2fat_clamp_testcase *t,
+					 char *desc)
+{
+	strscpy(desc, t->name, KUNIT_PARAM_DESC_SIZE);
+}
+
+static void truncate_atime_testcase_desc(struct fat_truncate_atime_testcase *t,
+					 char *desc)
+{
+	strscpy(desc, t->name, KUNIT_PARAM_DESC_SIZE);
+}
+
+KUNIT_ARRAY_PARAM(fat_time, time_test_cases, time_testcase_desc);
+KUNIT_ARRAY_PARAM(fat_unix2fat_clamp, unix2fat_clamp_test_cases,
+		  unix2fat_clamp_testcase_desc);
+KUNIT_ARRAY_PARAM(fat_truncate_atime, truncate_atime_test_cases,
+		  truncate_atime_testcase_desc);
+
+static void fat_test_set_time_offset(struct msdos_sb_info *sbi, int time_offset)
+{
+	memset(sbi, 0, sizeof(*sbi));
+	sbi->options.tz_set = 1;
+	sbi->options.time_offset = time_offset;
+}
+
+static void fat_time_fat2unix_test(struct kunit *test)
+{
+	static struct msdos_sb_info fake_sb;
+	struct timespec64 ts;
+	struct fat_timestamp_testcase *testcase =
+		(struct fat_timestamp_testcase *)test->param_value;
+
+	fat_test_set_time_offset(&fake_sb, testcase->time_offset);
+
+	fat_time_fat2unix(&fake_sb, &ts,
+			  testcase->time,
+			  testcase->date,
+			  testcase->cs);
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->ts.tv_sec,
+			    ts.tv_sec,
+			    "Timestamp mismatch (seconds)\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->ts.tv_nsec,
+			    ts.tv_nsec,
+			    "Timestamp mismatch (nanoseconds)\n");
+}
+
+static void fat_time_unix2fat_test(struct kunit *test)
+{
+	static struct msdos_sb_info fake_sb;
+	__le16 date, time;
+	u8 cs;
+	struct fat_timestamp_testcase *testcase =
+		(struct fat_timestamp_testcase *)test->param_value;
+
+	fat_test_set_time_offset(&fake_sb, testcase->time_offset);
+
+	fat_time_unix2fat(&fake_sb, &testcase->ts,
+			  &time, &date, &cs);
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->time,
+			    time,
+			    "Time mismatch\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->date,
+			    date,
+			    "Date mismatch\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->cs,
+			    cs,
+			    "Centisecond mismatch\n");
+}
+
+static void fat_time_unix2fat_clamp_test(struct kunit *test)
+{
+	static struct msdos_sb_info fake_sb;
+	__le16 date, time;
+	u8 cs;
+	struct fat_unix2fat_clamp_testcase *testcase =
+		(struct fat_unix2fat_clamp_testcase *)test->param_value;
+
+	fat_test_set_time_offset(&fake_sb, testcase->time_offset);
+
+	fat_time_unix2fat(&fake_sb, &testcase->ts, &time, &date, &cs);
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->time,
+			    time,
+			    "Clamped time mismatch\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->date,
+			    date,
+			    "Clamped date mismatch\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->cs,
+			    cs,
+			    "Clamped centisecond mismatch\n");
+}
+
+static void fat_time_unix2fat_no_csec_test(struct kunit *test)
+{
+	static struct msdos_sb_info fake_sb;
+	struct timespec64 ts = {
+		.tv_sec = 946684799LL,
+		.tv_nsec = 0L,
+	};
+	__le16 date, time;
+
+	fat_test_set_time_offset(&fake_sb, 0);
+
+	fat_time_unix2fat(&fake_sb, &ts, &time, &date, NULL);
+	KUNIT_EXPECT_EQ_MSG(test,
+			    49021,
+			    le16_to_cpu(time),
+			    "Time mismatch without centiseconds\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    10143,
+			    le16_to_cpu(date),
+			    "Date mismatch without centiseconds\n");
+}
+
+static void fat_truncate_atime_test(struct kunit *test)
+{
+	static struct msdos_sb_info fake_sb;
+	struct timespec64 actual;
+	struct fat_truncate_atime_testcase *testcase =
+		(struct fat_truncate_atime_testcase *)test->param_value;
+
+	fat_test_set_time_offset(&fake_sb, testcase->time_offset);
+
+	actual = fat_truncate_atime(&fake_sb, &testcase->ts);
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->expected.tv_sec,
+			    actual.tv_sec,
+			    "Atime truncation seconds mismatch\n");
+	KUNIT_EXPECT_EQ_MSG(test,
+			    testcase->expected.tv_nsec,
+			    actual.tv_nsec,
+			    "Atime truncation nanoseconds mismatch\n");
+}
+
+static struct kunit_case fat_test_cases[] = {
+	KUNIT_CASE(fat_checksum_test),
+	KUNIT_CASE(fat_clus_to_blknr_test),
+	KUNIT_CASE(fat_get_blknr_offset_test),
+	KUNIT_CASE_PARAM(fat_time_fat2unix_test, fat_time_gen_params),
+	KUNIT_CASE_PARAM(fat_time_unix2fat_test, fat_time_gen_params),
+	KUNIT_CASE_PARAM(fat_time_unix2fat_clamp_test,
+			 fat_unix2fat_clamp_gen_params),
+	KUNIT_CASE(fat_time_unix2fat_no_csec_test),
+	KUNIT_CASE_PARAM(fat_truncate_atime_test,
+			 fat_truncate_atime_gen_params),
+	{},
+};
+
+static struct kunit_suite fat_test_suite = {
+	.name = "fat_test",
+	.test_cases = fat_test_cases,
+};
+
+kunit_test_suites(&fat_test_suite);
+
+MODULE_DESCRIPTION("KUnit tests for FAT filesystems");
+MODULE_LICENSE("GPL v2");