From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace 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 --- fs/ext4/fast_commit.h | 189 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 189 insertions(+) create mode 100644 fs/ext4/fast_commit.h (limited to 'fs/ext4/fast_commit.h') diff --git a/fs/ext4/fast_commit.h b/fs/ext4/fast_commit.h new file mode 100644 index 000000000..2f77a37fb --- /dev/null +++ b/fs/ext4/fast_commit.h @@ -0,0 +1,189 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __FAST_COMMIT_H__ +#define __FAST_COMMIT_H__ + +/* + * Note this file is present in e2fsprogs/lib/ext2fs/fast_commit.h and + * linux/fs/ext4/fast_commit.h. These file should always be byte identical. + */ + +/* Fast commit tags */ +#define EXT4_FC_TAG_ADD_RANGE 0x0001 +#define EXT4_FC_TAG_DEL_RANGE 0x0002 +#define EXT4_FC_TAG_CREAT 0x0003 +#define EXT4_FC_TAG_LINK 0x0004 +#define EXT4_FC_TAG_UNLINK 0x0005 +#define EXT4_FC_TAG_INODE 0x0006 +#define EXT4_FC_TAG_PAD 0x0007 +#define EXT4_FC_TAG_TAIL 0x0008 +#define EXT4_FC_TAG_HEAD 0x0009 + +#define EXT4_FC_SUPPORTED_FEATURES 0x0 + +/* On disk fast commit tlv value structures */ + +/* Fast commit on disk tag length structure */ +struct ext4_fc_tl { + __le16 fc_tag; + __le16 fc_len; +}; + +/* Value structure for tag EXT4_FC_TAG_HEAD. */ +struct ext4_fc_head { + __le32 fc_features; + __le32 fc_tid; +}; + +/* Value structure for EXT4_FC_TAG_ADD_RANGE. */ +struct ext4_fc_add_range { + __le32 fc_ino; + __u8 fc_ex[12]; +}; + +/* Value structure for tag EXT4_FC_TAG_DEL_RANGE. */ +struct ext4_fc_del_range { + __le32 fc_ino; + __le32 fc_lblk; + __le32 fc_len; +}; + +/* + * This is the value structure for tags EXT4_FC_TAG_CREAT, EXT4_FC_TAG_LINK + * and EXT4_FC_TAG_UNLINK. + */ +struct ext4_fc_dentry_info { + __le32 fc_parent_ino; + __le32 fc_ino; + __u8 fc_dname[]; +}; + +/* Value structure for EXT4_FC_TAG_INODE. */ +struct ext4_fc_inode { + __le32 fc_ino; + __u8 fc_raw_inode[]; +}; + +/* Value structure for tag EXT4_FC_TAG_TAIL. */ +struct ext4_fc_tail { + __le32 fc_tid; + __le32 fc_crc; +}; + +/* Tag base length */ +#define EXT4_FC_TAG_BASE_LEN (sizeof(struct ext4_fc_tl)) + +/* + * Fast commit status codes + */ +enum { + EXT4_FC_STATUS_OK = 0, + EXT4_FC_STATUS_INELIGIBLE, + EXT4_FC_STATUS_SKIPPED, + EXT4_FC_STATUS_FAILED, +}; + +/* + * Fast commit ineligiblity reasons: + */ +enum { + EXT4_FC_REASON_XATTR = 0, + EXT4_FC_REASON_CROSS_RENAME, + EXT4_FC_REASON_JOURNAL_FLAG_CHANGE, + EXT4_FC_REASON_NOMEM, + EXT4_FC_REASON_SWAP_BOOT, + EXT4_FC_REASON_RESIZE, + EXT4_FC_REASON_RENAME_DIR, + EXT4_FC_REASON_FALLOC_RANGE, + EXT4_FC_REASON_INODE_JOURNAL_DATA, + EXT4_FC_REASON_ENCRYPTED_FILENAME, + EXT4_FC_REASON_MIGRATE, + EXT4_FC_REASON_VERITY, + EXT4_FC_REASON_MOVE_EXT, + EXT4_FC_REASON_MAX +}; + +#ifdef __KERNEL__ +/* + * In memory list of dentry updates that are performed on the file + * system used by fast commit code. + */ +struct ext4_fc_dentry_update { + int fcd_op; /* Type of update create / unlink / link */ + int fcd_parent; /* Parent inode number */ + int fcd_ino; /* Inode number */ + struct name_snapshot fcd_name; /* Dirent name */ + struct list_head fcd_list; + struct list_head fcd_dilist; +}; + +struct ext4_fc_stats { + unsigned int fc_ineligible_reason_count[EXT4_FC_REASON_MAX]; + unsigned long fc_num_commits; + unsigned long fc_ineligible_commits; + unsigned long fc_failed_commits; + unsigned long fc_skipped_commits; + unsigned long fc_numblks; + u64 s_fc_avg_commit_time; +}; + +#define EXT4_FC_REPLAY_REALLOC_INCREMENT 4 + +/* + * Physical block regions added to different inodes due to fast commit + * recovery. These are set during the SCAN phase. During the replay phase, + * our allocator excludes these from its allocation. This ensures that + * we don't accidentally allocating a block that is going to be used by + * another inode. + */ +struct ext4_fc_alloc_region { + ext4_lblk_t lblk; + ext4_fsblk_t pblk; + int ino, len; +}; + +/* + * Fast commit replay state. + */ +struct ext4_fc_replay_state { + int fc_replay_num_tags; + int fc_replay_expected_off; + int fc_current_pass; + int fc_cur_tag; + int fc_crc; + struct ext4_fc_alloc_region *fc_regions; + int fc_regions_size, fc_regions_used, fc_regions_valid; + int *fc_modified_inodes; + int fc_modified_inodes_used, fc_modified_inodes_size; +}; + +#define region_last(__region) (((__region)->lblk) + ((__region)->len) - 1) +#endif + +static inline const char *tag2str(__u16 tag) +{ + switch (tag) { + case EXT4_FC_TAG_LINK: + return "ADD_ENTRY"; + case EXT4_FC_TAG_UNLINK: + return "DEL_ENTRY"; + case EXT4_FC_TAG_ADD_RANGE: + return "ADD_RANGE"; + case EXT4_FC_TAG_CREAT: + return "CREAT_DENTRY"; + case EXT4_FC_TAG_DEL_RANGE: + return "DEL_RANGE"; + case EXT4_FC_TAG_INODE: + return "INODE"; + case EXT4_FC_TAG_PAD: + return "PAD"; + case EXT4_FC_TAG_TAIL: + return "TAIL"; + case EXT4_FC_TAG_HEAD: + return "HEAD"; + default: + return "ERROR"; + } +} + +#endif /* __FAST_COMMIT_H__ */ -- cgit v1.3.1