Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 174 insertions, 0 deletions

diff --git a/fs/isofs/namei.c b/fs/isofs/namei.c
new file mode 100644
index 0000000000..58f80e1b3a
--- /dev/null
+++ b/fs/isofs/namei.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/isofs/namei.c
+ *
+ *  (C) 1992  Eric Youngdale Modified for ISO 9660 filesystem.
+ *
+ *  (C) 1991  Linus Torvalds - minix filesystem
+ */
+
+#include <linux/gfp.h>
+#include "isofs.h"
+
+/*
+ * ok, we cannot use strncmp, as the name is not in our data space.
+ * Thus we'll have to use isofs_match. No big problem. Match also makes
+ * some sanity tests.
+ */
+static int
+isofs_cmp(struct dentry *dentry, const char *compare, int dlen)
+{
+	struct qstr qstr;
+	qstr.name = compare;
+	qstr.len = dlen;
+	if (likely(!dentry->d_op))
+		return dentry->d_name.len != dlen || memcmp(dentry->d_name.name, compare, dlen);
+	return dentry->d_op->d_compare(NULL, dentry->d_name.len, dentry->d_name.name, &qstr);
+}
+
+/*
+ *	isofs_find_entry()
+ *
+ * finds an entry in the specified directory with the wanted name. It
+ * returns the inode number of the found entry, or 0 on error.
+ */
+static unsigned long
+isofs_find_entry(struct inode *dir, struct dentry *dentry,
+	unsigned long *block_rv, unsigned long *offset_rv,
+	char *tmpname, struct iso_directory_record *tmpde)
+{
+	unsigned long bufsize = ISOFS_BUFFER_SIZE(dir);
+	unsigned char bufbits = ISOFS_BUFFER_BITS(dir);
+	unsigned long block, f_pos, offset, block_saved, offset_saved;
+	struct buffer_head *bh = NULL;
+	struct isofs_sb_info *sbi = ISOFS_SB(dir->i_sb);
+
+	if (!ISOFS_I(dir)->i_first_extent)
+		return 0;
+
+	f_pos = 0;
+	offset = 0;
+	block = 0;
+
+	while (f_pos < dir->i_size) {
+		struct iso_directory_record *de;
+		int de_len, match, i, dlen;
+		char *dpnt;
+
+		if (!bh) {
+			bh = isofs_bread(dir, block);
+			if (!bh)
+				return 0;
+		}
+
+		de = (struct iso_directory_record *) (bh->b_data + offset);
+
+		de_len = *(unsigned char *) de;
+		if (!de_len) {
+			brelse(bh);
+			bh = NULL;
+			f_pos = (f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1);
+			block = f_pos >> bufbits;
+			offset = 0;
+			continue;
+		}
+
+		block_saved = bh->b_blocknr;
+		offset_saved = offset;
+		offset += de_len;
+		f_pos += de_len;
+
+		/* Make sure we have a full directory entry */
+		if (offset >= bufsize) {
+			int slop = bufsize - offset + de_len;
+			memcpy(tmpde, de, slop);
+			offset &= bufsize - 1;
+			block++;
+			brelse(bh);
+			bh = NULL;
+			if (offset) {
+				bh = isofs_bread(dir, block);
+				if (!bh)
+					return 0;
+				memcpy((void *) tmpde + slop, bh->b_data, offset);
+			}
+			de = tmpde;
+		}
+
+		dlen = de->name_len[0];
+		dpnt = de->name;
+		/* Basic sanity check, whether name doesn't exceed dir entry */
+		if (de_len < dlen + sizeof(struct iso_directory_record)) {
+			printk(KERN_NOTICE "iso9660: Corrupted directory entry"
+			       " in block %lu of inode %lu\n", block,
+			       dir->i_ino);
+			brelse(bh);
+			return 0;
+		}
+
+		if (sbi->s_rock &&
+		    ((i = get_rock_ridge_filename(de, tmpname, dir)))) {
+			dlen = i;	/* possibly -1 */
+			dpnt = tmpname;
+#ifdef CONFIG_JOLIET
+		} else if (sbi->s_joliet_level) {
+			dlen = get_joliet_filename(de, tmpname, dir);
+			dpnt = tmpname;
+#endif
+		} else if (sbi->s_mapping == 'a') {
+			dlen = get_acorn_filename(de, tmpname, dir);
+			dpnt = tmpname;
+		} else if (sbi->s_mapping == 'n') {
+			dlen = isofs_name_translate(de, tmpname, dir);
+			dpnt = tmpname;
+		}
+
+		/*
+		 * Skip hidden or associated files unless hide or showassoc,
+		 * respectively, is set
+		 */
+		match = 0;
+		if (dlen > 0 &&
+			(!sbi->s_hide ||
+				(!(de->flags[-sbi->s_high_sierra] & 1))) &&
+			(sbi->s_showassoc ||
+				(!(de->flags[-sbi->s_high_sierra] & 4)))) {
+			if (dpnt && (dlen > 1 || dpnt[0] > 1))
+				match = (isofs_cmp(dentry, dpnt, dlen) == 0);
+		}
+		if (match) {
+			isofs_normalize_block_and_offset(de,
+							 &block_saved,
+							 &offset_saved);
+			*block_rv = block_saved;
+			*offset_rv = offset_saved;
+			brelse(bh);
+			return 1;
+		}
+	}
+	brelse(bh);
+	return 0;
+}
+
+struct dentry *isofs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+	int found;
+	unsigned long block;
+	unsigned long offset;
+	struct inode *inode;
+	struct page *page;
+
+	page = alloc_page(GFP_USER);
+	if (!page)
+		return ERR_PTR(-ENOMEM);
+
+	found = isofs_find_entry(dir, dentry,
+				&block, &offset,
+				page_address(page),
+				1024 + page_address(page));
+	__free_page(page);
+
+	inode = found ? isofs_iget(dir->i_sb, block, offset) : NULL;
+
+	return d_splice_alias(inode, dentry);
+}