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, 356 insertions, 0 deletions

diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
new file mode 100644
index 000000000..5a1ca43b5
--- /dev/null
+++ b/include/uapi/asm-generic/siginfo.h
@@ -0,0 +1,356 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_ASM_GENERIC_SIGINFO_H
+#define _UAPI_ASM_GENERIC_SIGINFO_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+
+typedef union sigval {
+	int sival_int;
+	void __user *sival_ptr;
+} sigval_t;
+
+#define SI_MAX_SIZE	128
+
+/*
+ * The default "si_band" type is "long", as specified by POSIX.
+ * However, some architectures want to override this to "int"
+ * for historical compatibility reasons, so we allow that.
+ */
+#ifndef __ARCH_SI_BAND_T
+#define __ARCH_SI_BAND_T long
+#endif
+
+#ifndef __ARCH_SI_CLOCK_T
+#define __ARCH_SI_CLOCK_T __kernel_clock_t
+#endif
+
+#ifndef __ARCH_SI_ATTRIBUTES
+#define __ARCH_SI_ATTRIBUTES
+#endif
+
+/*
+ * Be careful when extending this union.  On 32bit siginfo_t is 32bit
+ * aligned.  Which means that a 64bit field or any other field that
+ * would increase the alignment of siginfo_t will break the ABI.
+ */
+union __sifields {
+	/* kill() */
+	struct {
+		__kernel_pid_t _pid;	/* sender's pid */
+		__kernel_uid32_t _uid;	/* sender's uid */
+	} _kill;
+
+	/* POSIX.1b timers */
+	struct {
+		__kernel_timer_t _tid;	/* timer id */
+		int _overrun;		/* overrun count */
+		sigval_t _sigval;	/* same as below */
+		int _sys_private;       /* Not used by the kernel. Historic leftover. Always 0. */
+	} _timer;
+
+	/* POSIX.1b signals */
+	struct {
+		__kernel_pid_t _pid;	/* sender's pid */
+		__kernel_uid32_t _uid;	/* sender's uid */
+		sigval_t _sigval;
+	} _rt;
+
+	/* SIGCHLD */
+	struct {
+		__kernel_pid_t _pid;	/* which child */
+		__kernel_uid32_t _uid;	/* sender's uid */
+		int _status;		/* exit code */
+		__ARCH_SI_CLOCK_T _utime;
+		__ARCH_SI_CLOCK_T _stime;
+	} _sigchld;
+
+	/* SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGTRAP, SIGEMT */
+	struct {
+		void __user *_addr; /* faulting insn/memory ref. */
+
+#define __ADDR_BND_PKEY_PAD  (__alignof__(void *) < sizeof(short) ? \
+			      sizeof(short) : __alignof__(void *))
+		union {
+			/* used on alpha and sparc */
+			int _trapno;	/* TRAP # which caused the signal */
+			/*
+			 * used when si_code=BUS_MCEERR_AR or
+			 * used when si_code=BUS_MCEERR_AO
+			 */
+			short _addr_lsb; /* LSB of the reported address */
+			/* used when si_code=SEGV_BNDERR */
+			struct {
+				char _dummy_bnd[__ADDR_BND_PKEY_PAD];
+				void __user *_lower;
+				void __user *_upper;
+			} _addr_bnd;
+			/* used when si_code=SEGV_PKUERR */
+			struct {
+				char _dummy_pkey[__ADDR_BND_PKEY_PAD];
+				__u32 _pkey;
+			} _addr_pkey;
+			/* used when si_code=TRAP_PERF */
+			struct {
+				unsigned long _data;
+				__u32 _type;
+				__u32 _flags;
+			} _perf;
+		};
+	} _sigfault;
+
+	/* SIGPOLL */
+	struct {
+		__ARCH_SI_BAND_T _band;	/* POLL_IN, POLL_OUT, POLL_MSG */
+		int _fd;
+	} _sigpoll;
+
+	/* SIGSYS */
+	struct {
+		void __user *_call_addr; /* calling user insn */
+		int _syscall;	/* triggering system call number */
+		unsigned int _arch;	/* AUDIT_ARCH_* of syscall */
+	} _sigsys;
+};
+
+#ifndef __ARCH_HAS_SWAPPED_SIGINFO
+#define __SIGINFO 			\
+struct {				\
+	int si_signo;			\
+	int si_errno;			\
+	int si_code;			\
+	union __sifields _sifields;	\
+}
+#else
+#define __SIGINFO 			\
+struct {				\
+	int si_signo;			\
+	int si_code;			\
+	int si_errno;			\
+	union __sifields _sifields;	\
+}
+#endif /* __ARCH_HAS_SWAPPED_SIGINFO */
+
+typedef struct siginfo {
+	union {
+		__SIGINFO;
+		int _si_pad[SI_MAX_SIZE/sizeof(int)];
+	};
+} __ARCH_SI_ATTRIBUTES siginfo_t;
+
+/*
+ * How these fields are to be accessed.
+ */
+#define si_pid		_sifields._kill._pid
+#define si_uid		_sifields._kill._uid
+#define si_tid		_sifields._timer._tid
+#define si_overrun	_sifields._timer._overrun
+#define si_sys_private  _sifields._timer._sys_private
+#define si_status	_sifields._sigchld._status
+#define si_utime	_sifields._sigchld._utime
+#define si_stime	_sifields._sigchld._stime
+#define si_value	_sifields._rt._sigval
+#define si_int		_sifields._rt._sigval.sival_int
+#define si_ptr		_sifields._rt._sigval.sival_ptr
+#define si_addr		_sifields._sigfault._addr
+#define si_trapno	_sifields._sigfault._trapno
+#define si_addr_lsb	_sifields._sigfault._addr_lsb
+#define si_lower	_sifields._sigfault._addr_bnd._lower
+#define si_upper	_sifields._sigfault._addr_bnd._upper
+#define si_pkey		_sifields._sigfault._addr_pkey._pkey
+#define si_perf_data	_sifields._sigfault._perf._data
+#define si_perf_type	_sifields._sigfault._perf._type
+#define si_perf_flags	_sifields._sigfault._perf._flags
+#define si_band		_sifields._sigpoll._band
+#define si_fd		_sifields._sigpoll._fd
+#define si_call_addr	_sifields._sigsys._call_addr
+#define si_syscall	_sifields._sigsys._syscall
+#define si_arch		_sifields._sigsys._arch
+
+/*
+ * si_code values
+ * Digital reserves positive values for kernel-generated signals.
+ */
+#define SI_USER		0		/* sent by kill, sigsend, raise */
+#define SI_KERNEL	0x80		/* sent by the kernel from somewhere */
+#define SI_QUEUE	-1		/* sent by sigqueue */
+#define SI_TIMER	-2		/* sent by timer expiration */
+#define SI_MESGQ	-3		/* sent by real time mesq state change */
+#define SI_ASYNCIO	-4		/* sent by AIO completion */
+#define SI_SIGIO	-5		/* sent by queued SIGIO */
+#define SI_TKILL	-6		/* sent by tkill system call */
+#define SI_DETHREAD	-7		/* sent by execve() killing subsidiary threads */
+#define SI_ASYNCNL	-60		/* sent by glibc async name lookup completion */
+
+#define SI_FROMUSER(siptr)	((siptr)->si_code <= 0)
+#define SI_FROMKERNEL(siptr)	((siptr)->si_code > 0)
+
+/*
+ * SIGILL si_codes
+ */
+#define ILL_ILLOPC	1	/* illegal opcode */
+#define ILL_ILLOPN	2	/* illegal operand */
+#define ILL_ILLADR	3	/* illegal addressing mode */
+#define ILL_ILLTRP	4	/* illegal trap */
+#define ILL_PRVOPC	5	/* privileged opcode */
+#define ILL_PRVREG	6	/* privileged register */
+#define ILL_COPROC	7	/* coprocessor error */
+#define ILL_BADSTK	8	/* internal stack error */
+#define ILL_BADIADDR	9	/* unimplemented instruction address */
+#define __ILL_BREAK	10	/* illegal break */
+#define __ILL_BNDMOD	11	/* bundle-update (modification) in progress */
+#define NSIGILL		11
+
+/*
+ * SIGFPE si_codes
+ */
+#define FPE_INTDIV	1	/* integer divide by zero */
+#define FPE_INTOVF	2	/* integer overflow */
+#define FPE_FLTDIV	3	/* floating point divide by zero */
+#define FPE_FLTOVF	4	/* floating point overflow */
+#define FPE_FLTUND	5	/* floating point underflow */
+#define FPE_FLTRES	6	/* floating point inexact result */
+#define FPE_FLTINV	7	/* floating point invalid operation */
+#define FPE_FLTSUB	8	/* subscript out of range */
+#define __FPE_DECOVF	9	/* decimal overflow */
+#define __FPE_DECDIV	10	/* decimal division by zero */
+#define __FPE_DECERR	11	/* packed decimal error */
+#define __FPE_INVASC	12	/* invalid ASCII digit */
+#define __FPE_INVDEC	13	/* invalid decimal digit */
+#define FPE_FLTUNK	14	/* undiagnosed floating-point exception */
+#define FPE_CONDTRAP	15	/* trap on condition */
+#define NSIGFPE		15
+
+/*
+ * SIGSEGV si_codes
+ */
+#define SEGV_MAPERR	1	/* address not mapped to object */
+#define SEGV_ACCERR	2	/* invalid permissions for mapped object */
+#define SEGV_BNDERR	3	/* failed address bound checks */
+#ifdef __ia64__
+# define __SEGV_PSTKOVF	4	/* paragraph stack overflow */
+#else
+# define SEGV_PKUERR	4	/* failed protection key checks */
+#endif
+#define SEGV_ACCADI	5	/* ADI not enabled for mapped object */
+#define SEGV_ADIDERR	6	/* Disrupting MCD error */
+#define SEGV_ADIPERR	7	/* Precise MCD exception */
+#define SEGV_MTEAERR	8	/* Asynchronous ARM MTE error */
+#define SEGV_MTESERR	9	/* Synchronous ARM MTE exception */
+#define SEGV_CPERR	10	/* Control protection fault */
+#define NSIGSEGV	10
+
+/*
+ * SIGBUS si_codes
+ */
+#define BUS_ADRALN	1	/* invalid address alignment */
+#define BUS_ADRERR	2	/* non-existent physical address */
+#define BUS_OBJERR	3	/* object specific hardware error */
+/* hardware memory error consumed on a machine check: action required */
+#define BUS_MCEERR_AR	4
+/* hardware memory error detected in process but not consumed: action optional*/
+#define BUS_MCEERR_AO	5
+#define NSIGBUS		5
+
+/*
+ * SIGTRAP si_codes
+ */
+#define TRAP_BRKPT	1	/* process breakpoint */
+#define TRAP_TRACE	2	/* process trace trap */
+#define TRAP_BRANCH     3	/* process taken branch trap */
+#define TRAP_HWBKPT     4	/* hardware breakpoint/watchpoint */
+#define TRAP_UNK	5	/* undiagnosed trap */
+#define TRAP_PERF	6	/* perf event with sigtrap=1 */
+#define NSIGTRAP	6
+
+/*
+ * There is an additional set of SIGTRAP si_codes used by ptrace
+ * that are of the form: ((PTRACE_EVENT_XXX << 8) | SIGTRAP)
+ */
+
+/*
+ * Flags for si_perf_flags if SIGTRAP si_code is TRAP_PERF.
+ */
+#define TRAP_PERF_FLAG_ASYNC (1u << 0)
+
+/*
+ * SIGCHLD si_codes
+ */
+#define CLD_EXITED	1	/* child has exited */
+#define CLD_KILLED	2	/* child was killed */
+#define CLD_DUMPED	3	/* child terminated abnormally */
+#define CLD_TRAPPED	4	/* traced child has trapped */
+#define CLD_STOPPED	5	/* child has stopped */
+#define CLD_CONTINUED	6	/* stopped child has continued */
+#define NSIGCHLD	6
+
+/*
+ * SIGPOLL (or any other signal without signal specific si_codes) si_codes
+ */
+#define POLL_IN		1	/* data input available */
+#define POLL_OUT	2	/* output buffers available */
+#define POLL_MSG	3	/* input message available */
+#define POLL_ERR	4	/* i/o error */
+#define POLL_PRI	5	/* high priority input available */
+#define POLL_HUP	6	/* device disconnected */
+#define NSIGPOLL	6
+
+/*
+ * SIGSYS si_codes
+ */
+#define SYS_SECCOMP	1	/* seccomp triggered */
+#define SYS_USER_DISPATCH 2	/* syscall user dispatch triggered */
+#define NSIGSYS		2
+
+/*
+ * SIGEMT si_codes
+ */
+#define EMT_TAGOVF	1	/* tag overflow */
+#define NSIGEMT		1
+
+/*
+ * sigevent definitions
+ * 
+ * It seems likely that SIGEV_THREAD will have to be handled from 
+ * userspace, libpthread transmuting it to SIGEV_SIGNAL, which the
+ * thread manager then catches and does the appropriate nonsense.
+ * However, everything is written out here so as to not get lost.
+ */
+#define SIGEV_SIGNAL	0	/* notify via signal */
+#define SIGEV_NONE	1	/* other notification: meaningless */
+#define SIGEV_THREAD	2	/* deliver via thread creation */
+#define SIGEV_THREAD_ID 4	/* deliver to thread */
+
+/*
+ * This works because the alignment is ok on all current architectures
+ * but we leave open this being overridden in the future
+ */
+#ifndef __ARCH_SIGEV_PREAMBLE_SIZE
+#define __ARCH_SIGEV_PREAMBLE_SIZE	(sizeof(int) * 2 + sizeof(sigval_t))
+#endif
+
+#define SIGEV_MAX_SIZE	64
+#define SIGEV_PAD_SIZE	((SIGEV_MAX_SIZE - __ARCH_SIGEV_PREAMBLE_SIZE) \
+		/ sizeof(int))
+
+typedef struct sigevent {
+	sigval_t sigev_value;
+	int sigev_signo;
+	int sigev_notify;
+	union {
+		int _pad[SIGEV_PAD_SIZE];
+		 int _tid;
+
+		struct {
+			void (*_function)(sigval_t);
+			void *_attribute;	/* really pthread_attr_t */
+		} _sigev_thread;
+	} _sigev_un;
+} sigevent_t;
+
+#define sigev_notify_function	_sigev_un._sigev_thread._function
+#define sigev_notify_attributes	_sigev_un._sigev_thread._attribute
+#define sigev_notify_thread_id	 _sigev_un._tid
+
+
+#endif /* _UAPI_ASM_GENERIC_SIGINFO_H */