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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /fs/jffs2/read.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'fs/jffs2/read.c')
| -rw-r--r-- | fs/jffs2/read.c | 228 |
1 files changed, 228 insertions, 0 deletions
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 <dwmw2@infradead.org> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/crc32.h> +#include <linux/pagemap.h> +#include <linux/mtd/mtd.h> +#include <linux/compiler.h> +#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; +} + |
