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, 305 insertions, 0 deletions

diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
new file mode 100644
index 000000000..48cd64eb2
--- /dev/null
+++ b/fs/ubifs/debug.h
@@ -0,0 +1,305 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+#ifndef __UBIFS_DEBUG_H__
+#define __UBIFS_DEBUG_H__
+
+/* Checking helper functions */
+typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
+				 struct ubifs_zbranch *zbr, void *priv);
+typedef int (*dbg_znode_callback)(struct ubifs_info *c,
+				  struct ubifs_znode *znode, void *priv);
+
+/*
+ * The UBIFS debugfs directory name pattern and maximum name length (3 for "ubi"
+ * + 1 for "_" and 2 for UBI device numbers and 3 for volume number and 1 for
+ * the trailing zero byte.
+ */
+#define UBIFS_DFS_DIR_NAME "ubi%d_%d"
+#define UBIFS_DFS_DIR_LEN  (3 + 1 + 2 + 3 + 1)
+
+/**
+ * struct ubifs_debug_info - per-FS debugging information.
+ * @old_zroot: old index root - used by 'dbg_check_old_index()'
+ * @old_zroot_level: old index root level - used by 'dbg_check_old_index()'
+ * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()'
+ *
+ * @pc_happened: non-zero if an emulated power cut happened
+ * @pc_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls
+ * @pc_timeout: time in jiffies when delay of failure mode expires
+ * @pc_cnt: current number of calls to failure mode I/O functions
+ * @pc_cnt_max: number of calls by which to delay failure mode
+ *
+ * @chk_lpt_sz: used by LPT tree size checker
+ * @chk_lpt_sz2: used by LPT tree size checker
+ * @chk_lpt_wastage: used by LPT tree size checker
+ * @chk_lpt_lebs: used by LPT tree size checker
+ * @new_nhead_offs: used by LPT tree size checker
+ * @new_ihead_lnum: used by debugging to check @c->ihead_lnum
+ * @new_ihead_offs: used by debugging to check @c->ihead_offs
+ *
+ * @saved_lst: saved lprops statistics (used by 'dbg_save_space_info()')
+ * @saved_bi: saved budgeting information
+ * @saved_free: saved amount of free space
+ * @saved_idx_gc_cnt: saved value of @c->idx_gc_cnt
+ *
+ * @chk_gen: if general extra checks are enabled
+ * @chk_index: if index xtra checks are enabled
+ * @chk_orph: if orphans extra checks are enabled
+ * @chk_lprops: if lprops extra checks are enabled
+ * @chk_fs: if UBIFS contents extra checks are enabled
+ * @tst_rcvry: if UBIFS recovery testing mode enabled
+ *
+ * @dfs_dir_name: name of debugfs directory containing this file-system's files
+ * @dfs_dir: direntry object of the file-system debugfs directory
+ * @dfs_dump_lprops: "dump lprops" debugfs knob
+ * @dfs_dump_budg: "dump budgeting information" debugfs knob
+ * @dfs_dump_tnc: "dump TNC" debugfs knob
+ * @dfs_chk_gen: debugfs knob to enable UBIFS general extra checks
+ * @dfs_chk_index: debugfs knob to enable UBIFS index extra checks
+ * @dfs_chk_orph: debugfs knob to enable UBIFS orphans extra checks
+ * @dfs_chk_lprops: debugfs knob to enable UBIFS LEP properties extra checks
+ * @dfs_chk_fs: debugfs knob to enable UBIFS contents extra checks
+ * @dfs_tst_rcvry: debugfs knob to enable UBIFS recovery testing
+ * @dfs_ro_error: debugfs knob to switch UBIFS to R/O mode (different to
+ *                re-mounting to R/O mode because it does not flush any buffers
+ *                and UBIFS just starts returning -EROFS on all write
+ *               operations)
+ */
+struct ubifs_debug_info {
+	struct ubifs_zbranch old_zroot;
+	int old_zroot_level;
+	unsigned long long old_zroot_sqnum;
+
+	int pc_happened;
+	int pc_delay;
+	unsigned long pc_timeout;
+	unsigned int pc_cnt;
+	unsigned int pc_cnt_max;
+
+	long long chk_lpt_sz;
+	long long chk_lpt_sz2;
+	long long chk_lpt_wastage;
+	int chk_lpt_lebs;
+	int new_nhead_offs;
+	int new_ihead_lnum;
+	int new_ihead_offs;
+
+	struct ubifs_lp_stats saved_lst;
+	struct ubifs_budg_info saved_bi;
+	long long saved_free;
+	int saved_idx_gc_cnt;
+
+	unsigned int chk_gen:1;
+	unsigned int chk_index:1;
+	unsigned int chk_orph:1;
+	unsigned int chk_lprops:1;
+	unsigned int chk_fs:1;
+	unsigned int tst_rcvry:1;
+
+	char dfs_dir_name[UBIFS_DFS_DIR_LEN];
+	struct dentry *dfs_dir;
+	struct dentry *dfs_dump_lprops;
+	struct dentry *dfs_dump_budg;
+	struct dentry *dfs_dump_tnc;
+	struct dentry *dfs_chk_gen;
+	struct dentry *dfs_chk_index;
+	struct dentry *dfs_chk_orph;
+	struct dentry *dfs_chk_lprops;
+	struct dentry *dfs_chk_fs;
+	struct dentry *dfs_tst_rcvry;
+	struct dentry *dfs_ro_error;
+};
+
+/**
+ * struct ubifs_global_debug_info - global (not per-FS) UBIFS debugging information.
+ *
+ * @chk_gen: if general extra checks are enabled
+ * @chk_index: if index xtra checks are enabled
+ * @chk_orph: if orphans extra checks are enabled
+ * @chk_lprops: if lprops extra checks are enabled
+ * @chk_fs: if UBIFS contents extra checks are enabled
+ * @tst_rcvry: if UBIFS recovery testing mode enabled
+ */
+struct ubifs_global_debug_info {
+	unsigned int chk_gen:1;
+	unsigned int chk_index:1;
+	unsigned int chk_orph:1;
+	unsigned int chk_lprops:1;
+	unsigned int chk_fs:1;
+	unsigned int tst_rcvry:1;
+};
+
+void ubifs_assert_failed(struct ubifs_info *c, const char *expr,
+	const char *file, int line);
+
+#define ubifs_assert(c, expr) do {                                             \
+	if (unlikely(!(expr))) {                                               \
+		ubifs_assert_failed((struct ubifs_info *)c, #expr, __FILE__,   \
+		 __LINE__);                                                    \
+	}                                                                      \
+} while (0)
+
+#define ubifs_assert_cmt_locked(c) do {                                        \
+	if (unlikely(down_write_trylock(&(c)->commit_sem))) {                  \
+		up_write(&(c)->commit_sem);                                    \
+		ubifs_err(c, "commit lock is not locked!\n");                  \
+		ubifs_assert(c, 0);                                            \
+	}                                                                      \
+} while (0)
+
+#define ubifs_dbg_msg(type, fmt, ...) \
+	pr_debug("UBIFS DBG " type " (pid %d): " fmt "\n", current->pid,       \
+		 ##__VA_ARGS__)
+
+#define DBG_KEY_BUF_LEN 48
+#define ubifs_dbg_msg_key(type, key, fmt, ...) do {                            \
+	char __tmp_key_buf[DBG_KEY_BUF_LEN];                                   \
+	pr_debug("UBIFS DBG " type " (pid %d): " fmt "%s\n", current->pid,     \
+		 ##__VA_ARGS__,                                                \
+		 dbg_snprintf_key(c, key, __tmp_key_buf, DBG_KEY_BUF_LEN));    \
+} while (0)
+
+/* General messages */
+#define dbg_gen(fmt, ...)   ubifs_dbg_msg("gen", fmt, ##__VA_ARGS__)
+/* Additional journal messages */
+#define dbg_jnl(fmt, ...)   ubifs_dbg_msg("jnl", fmt, ##__VA_ARGS__)
+#define dbg_jnlk(key, fmt, ...) \
+	ubifs_dbg_msg_key("jnl", key, fmt, ##__VA_ARGS__)
+/* Additional TNC messages */
+#define dbg_tnc(fmt, ...)   ubifs_dbg_msg("tnc", fmt, ##__VA_ARGS__)
+#define dbg_tnck(key, fmt, ...) \
+	ubifs_dbg_msg_key("tnc", key, fmt, ##__VA_ARGS__)
+/* Additional lprops messages */
+#define dbg_lp(fmt, ...)    ubifs_dbg_msg("lp", fmt, ##__VA_ARGS__)
+/* Additional LEB find messages */
+#define dbg_find(fmt, ...)  ubifs_dbg_msg("find", fmt, ##__VA_ARGS__)
+/* Additional mount messages */
+#define dbg_mnt(fmt, ...)   ubifs_dbg_msg("mnt", fmt, ##__VA_ARGS__)
+#define dbg_mntk(key, fmt, ...) \
+	ubifs_dbg_msg_key("mnt", key, fmt, ##__VA_ARGS__)
+/* Additional I/O messages */
+#define dbg_io(fmt, ...)    ubifs_dbg_msg("io", fmt, ##__VA_ARGS__)
+/* Additional commit messages */
+#define dbg_cmt(fmt, ...)   ubifs_dbg_msg("cmt", fmt, ##__VA_ARGS__)
+/* Additional budgeting messages */
+#define dbg_budg(fmt, ...)  ubifs_dbg_msg("budg", fmt, ##__VA_ARGS__)
+/* Additional log messages */
+#define dbg_log(fmt, ...)   ubifs_dbg_msg("log", fmt, ##__VA_ARGS__)
+/* Additional gc messages */
+#define dbg_gc(fmt, ...)    ubifs_dbg_msg("gc", fmt, ##__VA_ARGS__)
+/* Additional scan messages */
+#define dbg_scan(fmt, ...)  ubifs_dbg_msg("scan", fmt, ##__VA_ARGS__)
+/* Additional recovery messages */
+#define dbg_rcvry(fmt, ...) ubifs_dbg_msg("rcvry", fmt, ##__VA_ARGS__)
+
+extern struct ubifs_global_debug_info ubifs_dbg;
+
+static inline int dbg_is_chk_gen(const struct ubifs_info *c)
+{
+	return !!(ubifs_dbg.chk_gen || c->dbg->chk_gen);
+}
+static inline int dbg_is_chk_index(const struct ubifs_info *c)
+{
+	return !!(ubifs_dbg.chk_index || c->dbg->chk_index);
+}
+static inline int dbg_is_chk_orph(const struct ubifs_info *c)
+{
+	return !!(ubifs_dbg.chk_orph || c->dbg->chk_orph);
+}
+static inline int dbg_is_chk_lprops(const struct ubifs_info *c)
+{
+	return !!(ubifs_dbg.chk_lprops || c->dbg->chk_lprops);
+}
+static inline int dbg_is_chk_fs(const struct ubifs_info *c)
+{
+	return !!(ubifs_dbg.chk_fs || c->dbg->chk_fs);
+}
+static inline int dbg_is_tst_rcvry(const struct ubifs_info *c)
+{
+	return !!(ubifs_dbg.tst_rcvry || c->dbg->tst_rcvry);
+}
+static inline int dbg_is_power_cut(const struct ubifs_info *c)
+{
+	return !!c->dbg->pc_happened;
+}
+
+int ubifs_debugging_init(struct ubifs_info *c);
+void ubifs_debugging_exit(struct ubifs_info *c);
+
+/* Dump functions */
+const char *dbg_ntype(int type);
+const char *dbg_cstate(int cmt_state);
+const char *dbg_jhead(int jhead);
+const char *dbg_get_key_dump(const struct ubifs_info *c,
+			     const union ubifs_key *key);
+const char *dbg_snprintf_key(const struct ubifs_info *c,
+			     const union ubifs_key *key, char *buffer, int len);
+void ubifs_dump_inode(struct ubifs_info *c, const struct inode *inode);
+void ubifs_dump_node(const struct ubifs_info *c, const void *node,
+		     int node_len);
+void ubifs_dump_budget_req(const struct ubifs_budget_req *req);
+void ubifs_dump_lstats(const struct ubifs_lp_stats *lst);
+void ubifs_dump_budg(struct ubifs_info *c, const struct ubifs_budg_info *bi);
+void ubifs_dump_lprop(const struct ubifs_info *c,
+		      const struct ubifs_lprops *lp);
+void ubifs_dump_lprops(struct ubifs_info *c);
+void ubifs_dump_lpt_info(struct ubifs_info *c);
+void ubifs_dump_leb(const struct ubifs_info *c, int lnum);
+void ubifs_dump_znode(const struct ubifs_info *c,
+		      const struct ubifs_znode *znode);
+void ubifs_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+		     int cat);
+void ubifs_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+		      struct ubifs_nnode *parent, int iip);
+void ubifs_dump_tnc(struct ubifs_info *c);
+void ubifs_dump_index(struct ubifs_info *c);
+void ubifs_dump_lpt_lebs(const struct ubifs_info *c);
+
+int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
+		   dbg_znode_callback znode_cb, void *priv);
+
+/* Checking functions */
+void dbg_save_space_info(struct ubifs_info *c);
+int dbg_check_space_info(struct ubifs_info *c);
+int dbg_check_lprops(struct ubifs_info *c);
+int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+int dbg_check_cats(struct ubifs_info *c);
+int dbg_check_ltab(struct ubifs_info *c);
+int dbg_chk_lpt_free_spc(struct ubifs_info *c);
+int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len);
+int dbg_check_synced_i_size(const struct ubifs_info *c, struct inode *inode);
+int dbg_check_dir(struct ubifs_info *c, const struct inode *dir);
+int dbg_check_tnc(struct ubifs_info *c, int extra);
+int dbg_check_idx_size(struct ubifs_info *c, long long idx_size);
+int dbg_check_filesystem(struct ubifs_info *c);
+void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
+		    int add_pos);
+int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
+			int row, int col);
+int dbg_check_inode_size(struct ubifs_info *c, const struct inode *inode,
+			 loff_t size);
+int dbg_check_data_nodes_order(struct ubifs_info *c, struct list_head *head);
+int dbg_check_nondata_nodes_order(struct ubifs_info *c, struct list_head *head);
+
+int dbg_leb_write(struct ubifs_info *c, int lnum, const void *buf, int offs,
+		  int len);
+int dbg_leb_change(struct ubifs_info *c, int lnum, const void *buf, int len);
+int dbg_leb_unmap(struct ubifs_info *c, int lnum);
+int dbg_leb_map(struct ubifs_info *c, int lnum);
+
+/* Debugfs-related stuff */
+void dbg_debugfs_init(void);
+void dbg_debugfs_exit(void);
+void dbg_debugfs_init_fs(struct ubifs_info *c);
+void dbg_debugfs_exit_fs(struct ubifs_info *c);
+
+#endif /* !__UBIFS_DEBUG_H__ */