summaryrefslogtreecommitdiffstats
path: root/fs/squashfs/dir.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/squashfs/dir.c
downloadlinux-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/squashfs/dir.c')
-rw-r--r--fs/squashfs/dir.c225
1 files changed, 225 insertions, 0 deletions
diff --git a/fs/squashfs/dir.c b/fs/squashfs/dir.c
new file mode 100644
index 000000000..cd3598bd0
--- /dev/null
+++ b/fs/squashfs/dir.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip@squashfs.org.uk>
+ *
+ * dir.c
+ */
+
+/*
+ * This file implements code to read directories from disk.
+ *
+ * See namei.c for a description of directory organisation on disk.
+ */
+
+#include <linux/fs.h>
+#include <linux/filelock.h>
+#include <linux/vfs.h>
+#include <linux/slab.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+static const unsigned char squashfs_filetype_table[] = {
+ DT_UNKNOWN, DT_DIR, DT_REG, DT_LNK, DT_BLK, DT_CHR, DT_FIFO, DT_SOCK
+};
+
+/*
+ * Lookup offset (f_pos) in the directory index, returning the
+ * metadata block containing it.
+ *
+ * If we get an error reading the index then return the part of the index
+ * (if any) we have managed to read - the index isn't essential, just
+ * quicker.
+ */
+static int get_dir_index_using_offset(struct super_block *sb,
+ u64 *next_block, int *next_offset, u64 index_start, int index_offset,
+ int i_count, u64 f_pos)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ int err, i, index, length = 0;
+ unsigned int size;
+ struct squashfs_dir_index dir_index;
+
+ TRACE("Entered get_dir_index_using_offset, i_count %d, f_pos %lld\n",
+ i_count, f_pos);
+
+ /*
+ * Translate from external f_pos to the internal f_pos. This
+ * is offset by 3 because we invent "." and ".." entries which are
+ * not actually stored in the directory.
+ */
+ if (f_pos <= 3)
+ return f_pos;
+ f_pos -= 3;
+
+ for (i = 0; i < i_count; i++) {
+ err = squashfs_read_metadata(sb, &dir_index, &index_start,
+ &index_offset, sizeof(dir_index));
+ if (err < 0)
+ break;
+
+ index = le32_to_cpu(dir_index.index);
+ if (index > f_pos)
+ /*
+ * Found the index we're looking for.
+ */
+ break;
+
+ size = le32_to_cpu(dir_index.size) + 1;
+
+ /* size should never be larger than SQUASHFS_NAME_LEN */
+ if (size > SQUASHFS_NAME_LEN)
+ break;
+
+ err = squashfs_read_metadata(sb, NULL, &index_start,
+ &index_offset, size);
+ if (err < 0)
+ break;
+
+ length = index;
+ *next_block = le32_to_cpu(dir_index.start_block) +
+ msblk->directory_table;
+ }
+
+ *next_offset = (length + *next_offset) % SQUASHFS_METADATA_SIZE;
+
+ /*
+ * Translate back from internal f_pos to external f_pos.
+ */
+ return length + 3;
+}
+
+
+static int squashfs_readdir(struct file *file, struct dir_context *ctx)
+{
+ struct inode *inode = file_inode(file);
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ u64 block = squashfs_i(inode)->start + msblk->directory_table;
+ int offset = squashfs_i(inode)->offset, length, err;
+ unsigned int inode_number, dir_count, size, type;
+ struct squashfs_dir_header dirh;
+ struct squashfs_dir_entry *dire;
+
+ TRACE("Entered squashfs_readdir [%llx:%x]\n", block, offset);
+
+ dire = kmalloc(sizeof(*dire) + SQUASHFS_NAME_LEN + 1, GFP_KERNEL);
+ if (dire == NULL) {
+ ERROR("Failed to allocate squashfs_dir_entry\n");
+ goto finish;
+ }
+
+ /*
+ * Return "." and ".." entries as the first two filenames in the
+ * directory. To maximise compression these two entries are not
+ * stored in the directory, and so we invent them here.
+ *
+ * It also means that the external f_pos is offset by 3 from the
+ * on-disk directory f_pos.
+ */
+ while (ctx->pos < 3) {
+ char *name;
+ int i_ino;
+
+ if (ctx->pos == 0) {
+ name = ".";
+ size = 1;
+ i_ino = inode->i_ino;
+ } else {
+ name = "..";
+ size = 2;
+ i_ino = squashfs_i(inode)->parent;
+ }
+
+ if (!dir_emit(ctx, name, size, i_ino,
+ squashfs_filetype_table[1]))
+ goto finish;
+
+ ctx->pos += size;
+ }
+
+ length = get_dir_index_using_offset(inode->i_sb, &block, &offset,
+ squashfs_i(inode)->dir_idx_start,
+ squashfs_i(inode)->dir_idx_offset,
+ squashfs_i(inode)->dir_idx_cnt,
+ ctx->pos);
+
+ while (length < i_size_read(inode)) {
+ /*
+ * Read directory header
+ */
+ err = squashfs_read_metadata(inode->i_sb, &dirh, &block,
+ &offset, sizeof(dirh));
+ if (err < 0)
+ goto failed_read;
+
+ length += sizeof(dirh);
+
+ dir_count = le32_to_cpu(dirh.count) + 1;
+
+ if (dir_count > SQUASHFS_DIR_COUNT)
+ goto failed_read;
+
+ while (dir_count--) {
+ /*
+ * Read directory entry.
+ */
+ err = squashfs_read_metadata(inode->i_sb, dire, &block,
+ &offset, sizeof(*dire));
+ if (err < 0)
+ goto failed_read;
+
+ size = le16_to_cpu(dire->size) + 1;
+
+ /* size should never be larger than SQUASHFS_NAME_LEN */
+ if (size > SQUASHFS_NAME_LEN)
+ goto failed_read;
+
+ err = squashfs_read_metadata(inode->i_sb, dire->name,
+ &block, &offset, size);
+ if (err < 0)
+ goto failed_read;
+
+ length += sizeof(*dire) + size;
+
+ if (ctx->pos >= length)
+ continue;
+
+ dire->name[size] = '\0';
+ inode_number = le32_to_cpu(dirh.inode_number) +
+ ((short) le16_to_cpu(dire->inode_number));
+ type = le16_to_cpu(dire->type);
+
+ if (type > SQUASHFS_MAX_DIR_TYPE)
+ goto failed_read;
+
+ if (!dir_emit(ctx, dire->name, size,
+ inode_number,
+ squashfs_filetype_table[type]))
+ goto finish;
+
+ ctx->pos = length;
+ }
+ }
+
+finish:
+ kfree(dire);
+ return 0;
+
+failed_read:
+ ERROR("Unable to read directory block [%llx:%x]\n", block, offset);
+ kfree(dire);
+ return 0;
+}
+
+
+const struct file_operations squashfs_dir_ops = {
+ .read = generic_read_dir,
+ .iterate_shared = squashfs_readdir,
+ .llseek = generic_file_llseek,
+ .setlease = generic_setlease,
+};