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/jffs2/read.c | 228 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 228 insertions(+) create mode 100644 fs/jffs2/read.c (limited to 'fs/jffs2/read.c') diff --git a/fs/jffs2/read.c b/fs/jffs2/read.c new file mode 100644 index 000000000..0b042b1fc --- /dev/null +++ b/fs/jffs2/read.c @@ -0,0 +1,228 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright © 2001-2007 Red Hat, Inc. + * + * Created by David Woodhouse + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include "nodelist.h" +#include "compr.h" + +int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, + struct jffs2_full_dnode *fd, unsigned char *buf, + int ofs, int len) +{ + struct jffs2_raw_inode *ri; + size_t readlen; + uint32_t crc; + unsigned char *decomprbuf = NULL; + unsigned char *readbuf = NULL; + int ret = 0; + + ri = jffs2_alloc_raw_inode(); + if (!ri) + return -ENOMEM; + + ret = jffs2_flash_read(c, ref_offset(fd->raw), sizeof(*ri), &readlen, (char *)ri); + if (ret) { + jffs2_free_raw_inode(ri); + pr_warn("Error reading node from 0x%08x: %d\n", + ref_offset(fd->raw), ret); + return ret; + } + if (readlen != sizeof(*ri)) { + jffs2_free_raw_inode(ri); + pr_warn("Short read from 0x%08x: wanted 0x%zx bytes, got 0x%zx\n", + ref_offset(fd->raw), sizeof(*ri), readlen); + return -EIO; + } + crc = crc32(0, ri, sizeof(*ri)-8); + + jffs2_dbg(1, "Node read from %08x: node_crc %08x, calculated CRC %08x. dsize %x, csize %x, offset %x, buf %p\n", + ref_offset(fd->raw), je32_to_cpu(ri->node_crc), + crc, je32_to_cpu(ri->dsize), je32_to_cpu(ri->csize), + je32_to_cpu(ri->offset), buf); + if (crc != je32_to_cpu(ri->node_crc)) { + pr_warn("Node CRC %08x != calculated CRC %08x for node at %08x\n", + je32_to_cpu(ri->node_crc), crc, ref_offset(fd->raw)); + ret = -EIO; + goto out_ri; + } + /* There was a bug where we wrote hole nodes out with csize/dsize + swapped. Deal with it */ + if (ri->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(ri->dsize) && + je32_to_cpu(ri->csize)) { + ri->dsize = ri->csize; + ri->csize = cpu_to_je32(0); + } + + D1(if(ofs + len > je32_to_cpu(ri->dsize)) { + pr_warn("jffs2_read_dnode() asked for %d bytes at %d from %d-byte node\n", + len, ofs, je32_to_cpu(ri->dsize)); + ret = -EINVAL; + goto out_ri; + }); + + + if (ri->compr == JFFS2_COMPR_ZERO) { + memset(buf, 0, len); + goto out_ri; + } + + /* Cases: + Reading whole node and it's uncompressed - read directly to buffer provided, check CRC. + Reading whole node and it's compressed - read into comprbuf, check CRC and decompress to buffer provided + Reading partial node and it's uncompressed - read into readbuf, check CRC, and copy + Reading partial node and it's compressed - read into readbuf, check checksum, decompress to decomprbuf and copy + */ + if (ri->compr == JFFS2_COMPR_NONE && len == je32_to_cpu(ri->dsize)) { + readbuf = buf; + } else { + readbuf = kmalloc(je32_to_cpu(ri->csize), GFP_KERNEL); + if (!readbuf) { + ret = -ENOMEM; + goto out_ri; + } + } + if (ri->compr != JFFS2_COMPR_NONE) { + if (len < je32_to_cpu(ri->dsize)) { + decomprbuf = kmalloc(je32_to_cpu(ri->dsize), GFP_KERNEL); + if (!decomprbuf) { + ret = -ENOMEM; + goto out_readbuf; + } + } else { + decomprbuf = buf; + } + } else { + decomprbuf = readbuf; + } + + jffs2_dbg(2, "Read %d bytes to %p\n", je32_to_cpu(ri->csize), + readbuf); + ret = jffs2_flash_read(c, (ref_offset(fd->raw)) + sizeof(*ri), + je32_to_cpu(ri->csize), &readlen, readbuf); + + if (!ret && readlen != je32_to_cpu(ri->csize)) + ret = -EIO; + if (ret) + goto out_decomprbuf; + + crc = crc32(0, readbuf, je32_to_cpu(ri->csize)); + if (crc != je32_to_cpu(ri->data_crc)) { + pr_warn("Data CRC %08x != calculated CRC %08x for node at %08x\n", + je32_to_cpu(ri->data_crc), crc, ref_offset(fd->raw)); + ret = -EIO; + goto out_decomprbuf; + } + jffs2_dbg(2, "Data CRC matches calculated CRC %08x\n", crc); + if (ri->compr != JFFS2_COMPR_NONE) { + jffs2_dbg(2, "Decompress %d bytes from %p to %d bytes at %p\n", + je32_to_cpu(ri->csize), readbuf, + je32_to_cpu(ri->dsize), decomprbuf); + ret = jffs2_decompress(c, f, ri->compr | (ri->usercompr << 8), readbuf, decomprbuf, je32_to_cpu(ri->csize), je32_to_cpu(ri->dsize)); + if (ret) { + pr_warn("Error: jffs2_decompress returned %d\n", ret); + goto out_decomprbuf; + } + } + + if (len < je32_to_cpu(ri->dsize)) { + memcpy(buf, decomprbuf+ofs, len); + } + out_decomprbuf: + if(decomprbuf != buf && decomprbuf != readbuf) + kfree(decomprbuf); + out_readbuf: + if(readbuf != buf) + kfree(readbuf); + out_ri: + jffs2_free_raw_inode(ri); + + return ret; +} + +int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f, + unsigned char *buf, uint32_t offset, uint32_t len) +{ + uint32_t end = offset + len; + struct jffs2_node_frag *frag; + int ret; + + jffs2_dbg(1, "%s(): ino #%u, range 0x%08x-0x%08x\n", + __func__, f->inocache->ino, offset, offset + len); + + frag = jffs2_lookup_node_frag(&f->fragtree, offset); + + /* XXX FIXME: Where a single physical node actually shows up in two + frags, we read it twice. Don't do that. */ + /* Now we're pointing at the first frag which overlaps our page + * (or perhaps is before it, if we've been asked to read off the + * end of the file). */ + while(offset < end) { + jffs2_dbg(2, "%s(): offset %d, end %d\n", + __func__, offset, end); + if (unlikely(!frag || frag->ofs > offset || + frag->ofs + frag->size <= offset)) { + uint32_t holesize = end - offset; + if (frag && frag->ofs > offset) { + jffs2_dbg(1, "Eep. Hole in ino #%u fraglist. frag->ofs = 0x%08x, offset = 0x%08x\n", + f->inocache->ino, frag->ofs, offset); + holesize = min(holesize, frag->ofs - offset); + } + jffs2_dbg(1, "Filling non-frag hole from %d-%d\n", + offset, offset + holesize); + memset(buf, 0, holesize); + buf += holesize; + offset += holesize; + continue; + } else if (unlikely(!frag->node)) { + uint32_t holeend = min(end, frag->ofs + frag->size); + jffs2_dbg(1, "Filling frag hole from %d-%d (frag 0x%x 0x%x)\n", + offset, holeend, frag->ofs, + frag->ofs + frag->size); + memset(buf, 0, holeend - offset); + buf += holeend - offset; + offset = holeend; + frag = frag_next(frag); + continue; + } else { + uint32_t readlen; + uint32_t fragofs; /* offset within the frag to start reading */ + + fragofs = offset - frag->ofs; + readlen = min(frag->size - fragofs, end - offset); + jffs2_dbg(1, "Reading %d-%d from node at 0x%08x (%d)\n", + frag->ofs+fragofs, + frag->ofs + fragofs+readlen, + ref_offset(frag->node->raw), + ref_flags(frag->node->raw)); + ret = jffs2_read_dnode(c, f, frag->node, buf, fragofs + frag->ofs - frag->node->ofs, readlen); + jffs2_dbg(2, "node read done\n"); + if (ret) { + jffs2_dbg(1, "%s(): error %d\n", + __func__, ret); + memset(buf, 0, readlen); + return ret; + } + buf += readlen; + offset += readlen; + frag = frag_next(frag); + jffs2_dbg(2, "node read was OK. Looping\n"); + } + } + return 0; +} + -- cgit v1.3.1