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/adfs/dir.c | 458 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 458 insertions(+) create mode 100644 fs/adfs/dir.c (limited to 'fs/adfs/dir.c') diff --git a/fs/adfs/dir.c b/fs/adfs/dir.c new file mode 100644 index 000000000..11afa9e15 --- /dev/null +++ b/fs/adfs/dir.c @@ -0,0 +1,458 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/adfs/dir.c + * + * Copyright (C) 1999-2000 Russell King + * + * Common directory handling for ADFS + */ +#include +#include +#include "adfs.h" + +/* + * For future. This should probably be per-directory. + */ +static DECLARE_RWSEM(adfs_dir_rwsem); + +int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset, + size_t len) +{ + struct super_block *sb = dir->sb; + unsigned int index, remain; + + index = offset >> sb->s_blocksize_bits; + offset &= sb->s_blocksize - 1; + remain = sb->s_blocksize - offset; + if (index + (remain < len) >= dir->nr_buffers) + return -EINVAL; + + if (remain < len) { + memcpy(dst, dir->bhs[index]->b_data + offset, remain); + dst += remain; + len -= remain; + index += 1; + offset = 0; + } + + memcpy(dst, dir->bhs[index]->b_data + offset, len); + + return 0; +} + +int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src, + size_t len) +{ + struct super_block *sb = dir->sb; + unsigned int index, remain; + + index = offset >> sb->s_blocksize_bits; + offset &= sb->s_blocksize - 1; + remain = sb->s_blocksize - offset; + if (index + (remain < len) >= dir->nr_buffers) + return -EINVAL; + + if (remain < len) { + memcpy(dir->bhs[index]->b_data + offset, src, remain); + src += remain; + len -= remain; + index += 1; + offset = 0; + } + + memcpy(dir->bhs[index]->b_data + offset, src, len); + + return 0; +} + +static void __adfs_dir_cleanup(struct adfs_dir *dir) +{ + dir->nr_buffers = 0; + + if (dir->bhs != dir->bh) + kfree(dir->bhs); + dir->bhs = NULL; + dir->sb = NULL; +} + +void adfs_dir_relse(struct adfs_dir *dir) +{ + unsigned int i; + + for (i = 0; i < dir->nr_buffers; i++) + brelse(dir->bhs[i]); + + __adfs_dir_cleanup(dir); +} + +static void adfs_dir_forget(struct adfs_dir *dir) +{ + unsigned int i; + + for (i = 0; i < dir->nr_buffers; i++) + bforget(dir->bhs[i]); + + __adfs_dir_cleanup(dir); +} + +int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr, + unsigned int size, struct adfs_dir *dir) +{ + struct buffer_head **bhs; + unsigned int i, num; + int block; + + num = ALIGN(size, sb->s_blocksize) >> sb->s_blocksize_bits; + if (num > ARRAY_SIZE(dir->bh)) { + /* We only allow one extension */ + if (dir->bhs != dir->bh) + return -EINVAL; + + bhs = kzalloc_objs(*bhs, num); + if (!bhs) + return -ENOMEM; + + if (dir->nr_buffers) + memcpy(bhs, dir->bhs, dir->nr_buffers * sizeof(*bhs)); + + dir->bhs = bhs; + } + + for (i = dir->nr_buffers; i < num; i++) { + block = __adfs_block_map(sb, indaddr, i); + if (!block) { + adfs_error(sb, "dir %06x has a hole at offset %u", + indaddr, i); + goto error; + } + + dir->bhs[i] = sb_bread(sb, block); + if (!dir->bhs[i]) { + adfs_error(sb, + "dir %06x failed read at offset %u, mapped block 0x%08x", + indaddr, i, block); + goto error; + } + + dir->nr_buffers++; + } + return 0; + +error: + adfs_dir_relse(dir); + + return -EIO; +} + +static int adfs_dir_read(struct super_block *sb, u32 indaddr, + unsigned int size, struct adfs_dir *dir) +{ + dir->sb = sb; + dir->bhs = dir->bh; + dir->nr_buffers = 0; + + return ADFS_SB(sb)->s_dir->read(sb, indaddr, size, dir); +} + +static int adfs_dir_read_inode(struct super_block *sb, struct inode *inode, + struct adfs_dir *dir) +{ + int ret; + + ret = adfs_dir_read(sb, ADFS_I(inode)->indaddr, inode->i_size, dir); + if (ret) + return ret; + + if (ADFS_I(inode)->parent_id != dir->parent_id) { + adfs_error(sb, + "parent directory id changed under me! (%06x but got %06x)\n", + ADFS_I(inode)->parent_id, dir->parent_id); + adfs_dir_relse(dir); + ret = -EIO; + } + + return ret; +} + +static void adfs_dir_mark_dirty(struct adfs_dir *dir) +{ + unsigned int i; + + /* Mark the buffers dirty */ + for (i = 0; i < dir->nr_buffers; i++) + mark_buffer_dirty(dir->bhs[i]); +} + +static int adfs_dir_sync(struct adfs_dir *dir) +{ + int err = 0; + int i; + + for (i = dir->nr_buffers - 1; i >= 0; i--) { + struct buffer_head *bh = dir->bhs[i]; + sync_dirty_buffer(bh); + if (buffer_req(bh) && !buffer_uptodate(bh)) + err = -EIO; + } + + return err; +} + +void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj) +{ + unsigned int dots, i; + + /* + * RISC OS allows the use of '/' in directory entry names, so we need + * to fix these up. '/' is typically used for FAT compatibility to + * represent '.', so do the same conversion here. In any case, '.' + * will never be in a RISC OS name since it is used as the pathname + * separator. Handle the case where we may generate a '.' or '..' + * name, replacing the first character with '^' (the RISC OS "parent + * directory" character.) + */ + for (i = dots = 0; i < obj->name_len; i++) + if (obj->name[i] == '/') { + obj->name[i] = '.'; + dots++; + } + + if (obj->name_len <= 2 && dots == obj->name_len) + obj->name[0] = '^'; + + /* + * If the object is a file, and the user requested the ,xyz hex + * filetype suffix to the name, check the filetype and append. + */ + if (!(obj->attr & ADFS_NDA_DIRECTORY) && ADFS_SB(dir->sb)->s_ftsuffix) { + u16 filetype = adfs_filetype(obj->loadaddr); + + if (filetype != ADFS_FILETYPE_NONE) { + obj->name[obj->name_len++] = ','; + obj->name[obj->name_len++] = hex_asc_lo(filetype >> 8); + obj->name[obj->name_len++] = hex_asc_lo(filetype >> 4); + obj->name[obj->name_len++] = hex_asc_lo(filetype >> 0); + } + } +} + +static int adfs_iterate(struct file *file, struct dir_context *ctx) +{ + struct inode *inode = file_inode(file); + struct super_block *sb = inode->i_sb; + const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; + struct adfs_dir dir; + int ret; + + down_read(&adfs_dir_rwsem); + ret = adfs_dir_read_inode(sb, inode, &dir); + if (ret) + goto unlock; + + if (ctx->pos == 0) { + if (!dir_emit_dot(file, ctx)) + goto unlock_relse; + ctx->pos = 1; + } + if (ctx->pos == 1) { + if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR)) + goto unlock_relse; + ctx->pos = 2; + } + + ret = ops->iterate(&dir, ctx); + +unlock_relse: + up_read(&adfs_dir_rwsem); + adfs_dir_relse(&dir); + return ret; + +unlock: + up_read(&adfs_dir_rwsem); + return ret; +} + +int +adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait) +{ + const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; + struct adfs_dir dir; + int ret; + + if (!IS_ENABLED(CONFIG_ADFS_FS_RW)) + return -EINVAL; + + if (!ops->update) + return -EINVAL; + + down_write(&adfs_dir_rwsem); + ret = adfs_dir_read(sb, obj->parent_id, 0, &dir); + if (ret) + goto unlock; + + ret = ops->update(&dir, obj); + if (ret) + goto forget; + + ret = ops->commit(&dir); + if (ret) + goto forget; + up_write(&adfs_dir_rwsem); + + adfs_dir_mark_dirty(&dir); + + if (wait) + ret = adfs_dir_sync(&dir); + + adfs_dir_relse(&dir); + return ret; + + /* + * If the updated failed because the entry wasn't found, we can + * just release the buffers. If it was any other error, forget + * the dirtied buffers so they aren't written back to the media. + */ +forget: + if (ret == -ENOENT) + adfs_dir_relse(&dir); + else + adfs_dir_forget(&dir); +unlock: + up_write(&adfs_dir_rwsem); + + return ret; +} + +static unsigned char adfs_tolower(unsigned char c) +{ + if (c >= 'A' && c <= 'Z') + c += 'a' - 'A'; + return c; +} + +static int __adfs_compare(const unsigned char *qstr, u32 qlen, + const char *str, u32 len) +{ + u32 i; + + if (qlen != len) + return 1; + + for (i = 0; i < qlen; i++) + if (adfs_tolower(qstr[i]) != adfs_tolower(str[i])) + return 1; + + return 0; +} + +static int adfs_dir_lookup_byname(struct inode *inode, const struct qstr *qstr, + struct object_info *obj) +{ + struct super_block *sb = inode->i_sb; + const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; + const unsigned char *name; + struct adfs_dir dir; + u32 name_len; + int ret; + + down_read(&adfs_dir_rwsem); + ret = adfs_dir_read_inode(sb, inode, &dir); + if (ret) + goto unlock; + + ret = ops->setpos(&dir, 0); + if (ret) + goto unlock_relse; + + ret = -ENOENT; + name = qstr->name; + name_len = qstr->len; + while (ops->getnext(&dir, obj) == 0) { + if (!__adfs_compare(name, name_len, obj->name, obj->name_len)) { + ret = 0; + break; + } + } + obj->parent_id = ADFS_I(inode)->indaddr; + +unlock_relse: + up_read(&adfs_dir_rwsem); + adfs_dir_relse(&dir); + return ret; + +unlock: + up_read(&adfs_dir_rwsem); + return ret; +} + +const struct file_operations adfs_dir_operations = { + .read = generic_read_dir, + .llseek = generic_file_llseek, + .iterate_shared = adfs_iterate, + .fsync = simple_fsync, +}; + +static int +adfs_hash(const struct dentry *parent, struct qstr *qstr) +{ + const unsigned char *name; + unsigned long hash; + u32 len; + + if (qstr->len > ADFS_SB(parent->d_sb)->s_namelen) + return -ENAMETOOLONG; + + len = qstr->len; + name = qstr->name; + hash = init_name_hash(parent); + while (len--) + hash = partial_name_hash(adfs_tolower(*name++), hash); + qstr->hash = end_name_hash(hash); + + return 0; +} + +/* + * Compare two names, taking note of the name length + * requirements of the underlying filesystem. + */ +static int adfs_compare(const struct dentry *dentry, unsigned int len, + const char *str, const struct qstr *qstr) +{ + return __adfs_compare(qstr->name, qstr->len, str, len); +} + +const struct dentry_operations adfs_dentry_operations = { + .d_hash = adfs_hash, + .d_compare = adfs_compare, +}; + +static struct dentry * +adfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) +{ + struct inode *inode = NULL; + struct object_info obj; + int error; + + error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj); + if (error == 0) { + /* + * This only returns NULL if get_empty_inode + * fails. + */ + inode = adfs_iget(dir->i_sb, &obj); + if (!inode) + inode = ERR_PTR(-EACCES); + } else if (error != -ENOENT) { + inode = ERR_PTR(error); + } + return d_splice_alias(inode, dentry); +} + +/* + * directories can handle most operations... + */ +const struct inode_operations adfs_dir_inode_operations = { + .lookup = adfs_lookup, + .setattr = adfs_setattr, +}; -- cgit v1.3.1