Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 232 insertions, 0 deletions

diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
new file mode 100644
index 000000000..883cfd7de
--- /dev/null
+++ b/include/uapi/asm-generic/fcntl.h
@@ -0,0 +1,232 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _ASM_GENERIC_FCNTL_H
+#define _ASM_GENERIC_FCNTL_H
+
+#include <linux/types.h>
+
+/*
+ * FMODE_EXEC is 0x20
+ * These cannot be used by userspace O_* until internal and external open
+ * flags are split.
+ * -Eric Paris
+ */
+
+/*
+ * When introducing new O_* bits, please check its uniqueness in fcntl_init().
+ */
+
+#define O_ACCMODE	3
+#define O_RDONLY	0
+#define O_WRONLY	(1 << 0)
+#define O_RDWR		(1 << 1)
+/* (1 << 2) must not be used -- it collides with flags on alpha, sparc */
+/* (1 << 3) must not be used -- it collides with flags on alpha, mips, parisc, sparc */
+/* (1 << 4) must not be used -- it collides with flags on mips */
+/* (1 << 5) is free */
+#ifndef O_CREAT
+#define O_CREAT		(1 << 6)	/* not fcntl */
+#endif
+#ifndef O_EXCL
+#define O_EXCL		(1 << 7)	/* not fcntl */
+#endif
+#ifndef O_NOCTTY
+#define O_NOCTTY	(1 << 8)	/* not fcntl */
+#endif
+#ifndef O_TRUNC
+#define O_TRUNC		(1 << 9)	/* not fcntl */
+#endif
+#ifndef O_APPEND
+#define O_APPEND	(1 << 10)
+#endif
+#ifndef O_NONBLOCK
+#define O_NONBLOCK	(1 << 11)
+#endif
+#ifndef O_DSYNC
+#define O_DSYNC		(1 << 12)	/* used to be O_SYNC, see below */
+#endif
+#ifndef FASYNC
+#define FASYNC		(1 << 13)	/* fcntl, for BSD compatibility */
+#endif
+#ifndef O_DIRECT
+#define O_DIRECT	(1 << 14)	/* direct disk access hint */
+#endif
+#ifndef O_LARGEFILE
+#define O_LARGEFILE	(1 << 15)
+#endif
+#ifndef O_DIRECTORY
+#define O_DIRECTORY	(1 << 16)	/* must be a directory */
+#endif
+#ifndef O_NOFOLLOW
+#define O_NOFOLLOW	(1 << 17)	/* don't follow links */
+#endif
+#ifndef O_NOATIME
+#define O_NOATIME	(1 << 18)
+#endif
+#ifndef O_CLOEXEC
+#define O_CLOEXEC	(1 << 19)	/* set close_on_exec */
+#endif
+
+/*
+ * Before Linux 2.6.33 only O_DSYNC semantics were implemented, but using
+ * the O_SYNC flag.  We continue to use the existing numerical value
+ * for O_DSYNC semantics now, but using the correct symbolic name for it.
+ * This new value is used to request true Posix O_SYNC semantics.  It is
+ * defined in this strange way to make sure applications compiled against
+ * new headers get at least O_DSYNC semantics on older kernels.
+ *
+ * This has the nice side-effect that we can simply test for O_DSYNC
+ * wherever we do not care if O_DSYNC or O_SYNC is used.
+ *
+ * Note: __O_SYNC must never be used directly.
+ */
+#ifndef O_SYNC
+#define __O_SYNC	(1 << 20)
+#define O_SYNC		(__O_SYNC|O_DSYNC)
+#endif
+
+#ifndef O_PATH
+#define O_PATH		(1 << 21)
+#endif
+
+#ifndef __O_TMPFILE
+#define __O_TMPFILE	(1 << 22)
+#endif
+
+#ifndef O_EMPTYPATH
+#define O_EMPTYPATH	(1 << 26)	/* allow empty path */
+#endif
+
+/* a horrid kludge trying to make sure that this will fail on old kernels */
+#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
+
+#ifndef O_NDELAY
+#define O_NDELAY	O_NONBLOCK
+#endif
+
+/* (1 << 23) must not be used -- it collides with flags on alpha, parisc, sparc */
+/* (1 << 24) must not be used -- it collides with flags on alpha, sparc */
+/* (1 << 25) must not be used -- it collides with flags on sparc */
+
+#define F_DUPFD		0	/* dup */
+#define F_GETFD		1	/* get close_on_exec */
+#define F_SETFD		2	/* set/clear close_on_exec */
+#define F_GETFL		3	/* get file->f_flags */
+#define F_SETFL		4	/* set file->f_flags */
+#ifndef F_GETLK
+#define F_GETLK		5
+#define F_SETLK		6
+#define F_SETLKW	7
+#endif
+#ifndef F_SETOWN
+#define F_SETOWN	8	/* for sockets. */
+#define F_GETOWN	9	/* for sockets. */
+#endif
+#ifndef F_SETSIG
+#define F_SETSIG	10	/* for sockets. */
+#define F_GETSIG	11	/* for sockets. */
+#endif
+
+#if __BITS_PER_LONG == 32 || defined(__KERNEL__)
+#ifndef F_GETLK64
+#define F_GETLK64	12	/*  using 'struct flock64' */
+#define F_SETLK64	13
+#define F_SETLKW64	14
+#endif
+#endif /* __BITS_PER_LONG == 32 || defined(__KERNEL__) */
+
+#ifndef F_SETOWN_EX
+#define F_SETOWN_EX	15
+#define F_GETOWN_EX	16
+#endif
+
+#ifndef F_GETOWNER_UIDS
+#define F_GETOWNER_UIDS	17
+#endif
+
+/*
+ * Open File Description Locks
+ *
+ * Usually record locks held by a process are released on *any* close and are
+ * not inherited across a fork().
+ *
+ * These cmd values will set locks that conflict with process-associated
+ * record  locks, but are "owned" by the open file description, not the
+ * process. This means that they are inherited across fork() like BSD (flock)
+ * locks, and they are only released automatically when the last reference to
+ * the the open file against which they were acquired is put.
+ */
+#define F_OFD_GETLK	36
+#define F_OFD_SETLK	37
+#define F_OFD_SETLKW	38
+
+#define F_OWNER_TID	0
+#define F_OWNER_PID	1
+#define F_OWNER_PGRP	2
+
+struct f_owner_ex {
+	int	type;
+	__kernel_pid_t	pid;
+};
+
+/* for F_[GET|SET]FL */
+#define FD_CLOEXEC	1	/* actually anything with low bit set goes */
+
+/* for posix fcntl() and lockf() */
+#ifndef F_RDLCK
+#define F_RDLCK		0
+#define F_WRLCK		1
+#define F_UNLCK		2
+#endif
+
+/* for old implementation of bsd flock () */
+#ifndef F_EXLCK
+#define F_EXLCK		4	/* or 3 */
+#define F_SHLCK		8	/* or 4 */
+#endif
+
+/* operations for bsd flock(), also used by the kernel implementation */
+#define LOCK_SH		1	/* shared lock */
+#define LOCK_EX		2	/* exclusive lock */
+#define LOCK_NB		4	/* or'd with one of the above to prevent
+				   blocking */
+#define LOCK_UN		8	/* remove lock */
+
+/*
+ * LOCK_MAND support has been removed from the kernel. We leave the symbols
+ * here to not break legacy builds, but these should not be used in new code.
+ */
+#define LOCK_MAND	32	/* This is a mandatory flock ... */
+#define LOCK_READ	64	/* which allows concurrent read operations */
+#define LOCK_WRITE	128	/* which allows concurrent write operations */
+#define LOCK_RW		192	/* which allows concurrent read & write ops */
+
+#define F_LINUX_SPECIFIC_BASE	1024
+
+#ifndef HAVE_ARCH_STRUCT_FLOCK
+struct flock {
+	short	l_type;
+	short	l_whence;
+	__kernel_off_t	l_start;
+	__kernel_off_t	l_len;
+	__kernel_pid_t	l_pid;
+#ifdef	__ARCH_FLOCK_EXTRA_SYSID
+	__ARCH_FLOCK_EXTRA_SYSID
+#endif
+#ifdef	__ARCH_FLOCK_PAD
+	__ARCH_FLOCK_PAD
+#endif
+};
+
+struct flock64 {
+	short  l_type;
+	short  l_whence;
+	__kernel_loff_t l_start;
+	__kernel_loff_t l_len;
+	__kernel_pid_t  l_pid;
+#ifdef	__ARCH_FLOCK64_PAD
+	__ARCH_FLOCK64_PAD
+#endif
+};
+#endif /* HAVE_ARCH_STRUCT_FLOCK */
+
+#endif /* _ASM_GENERIC_FCNTL_H */