Merge tag 'exfat-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat

Pull exfat updates from Namjae Jeon:

 - fix referencing wrong parent directory information during rename

 - introduce a sys_tz mount option to use system timezone

 - improve performance while zeroing a cluster with dirsync mount option

 - fix slab-out-bounds in exat_clear_bitmap() reported from syzbot

* tag 'exfat-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: check if cluster num is valid
  exfat: reduce block requests when zeroing a cluster
  block: add sync_blockdev_range()
  exfat: introduce mount option 'sys_tz'
  exfat: fix referencing wrong parent directory information after renaming

6 files changed, 47 insertions, 61 deletions

diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c
index 03f142307174..9f42f25fab92 100644
--- a/fs/exfat/balloc.c
+++ b/fs/exfat/balloc.c
@@ -148,7 +148,9 @@ int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync)
 	struct super_block *sb = inode->i_sb;
 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
 
-	WARN_ON(clu < EXFAT_FIRST_CLUSTER);
+	if (!is_valid_cluster(sbi, clu))
+		return -EINVAL;
+
 	ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
 	i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
 	b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
@@ -166,7 +168,9 @@ void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync)
 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
 	struct exfat_mount_options *opts = &sbi->options;
 
-	WARN_ON(clu < EXFAT_FIRST_CLUSTER);
+	if (!is_valid_cluster(sbi, clu))
+		return;
+
 	ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
 	i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
 	b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index c6800b880920..4a7a2308eb72 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -203,6 +203,7 @@ struct exfat_mount_options {
 	/* on error: continue, panic, remount-ro */
 	enum exfat_error_mode errors;
 	unsigned utf8:1, /* Use of UTF-8 character set */
+		 sys_tz:1, /* Use local timezone */
 		 discard:1, /* Issue discard requests on deletions */
 		 keep_last_dots:1; /* Keep trailing periods in paths */
 	int time_offset; /* Offset of timestamps from UTC (in minutes) */
@@ -381,6 +382,12 @@ static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi,
 		EXFAT_RESERVED_CLUSTERS;
 }
 
+static inline bool is_valid_cluster(struct exfat_sb_info *sbi,
+		unsigned int clus)
+{
+	return clus >= EXFAT_FIRST_CLUSTER && clus < sbi->num_clusters;
+}
+
 /* super.c */
 int exfat_set_volume_dirty(struct super_block *sb);
 int exfat_clear_volume_dirty(struct super_block *sb);
diff --git a/fs/exfat/fatent.c b/fs/exfat/fatent.c
index a3464e56a7e1..9de6a6b844c9 100644
--- a/fs/exfat/fatent.c
+++ b/fs/exfat/fatent.c
@@ -6,6 +6,7 @@
 #include <linux/slab.h>
 #include <asm/unaligned.h>
 #include <linux/buffer_head.h>
+#include <linux/blkdev.h>
 
 #include "exfat_raw.h"
 #include "exfat_fs.h"
@@ -81,12 +82,6 @@ int exfat_ent_set(struct super_block *sb, unsigned int loc,
 	return 0;
 }
 
-static inline bool is_valid_cluster(struct exfat_sb_info *sbi,
-		unsigned int clus)
-{
-	return clus >= EXFAT_FIRST_CLUSTER && clus < sbi->num_clusters;
-}
-
 int exfat_ent_get(struct super_block *sb, unsigned int loc,
 		unsigned int *content)
 {
@@ -274,10 +269,9 @@ int exfat_zeroed_cluster(struct inode *dir, unsigned int clu)
 {
 	struct super_block *sb = dir->i_sb;
 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
-	struct buffer_head *bhs[MAX_BUF_PER_PAGE];
-	int nr_bhs = MAX_BUF_PER_PAGE;
+	struct buffer_head *bh;
 	sector_t blknr, last_blknr;
-	int err, i, n;
+	int i;
 
 	blknr = exfat_cluster_to_sector(sbi, clu);
 	last_blknr = blknr + sbi->sect_per_clus;
@@ -291,30 +285,23 @@ int exfat_zeroed_cluster(struct inode *dir, unsigned int clu)
 	}
 
 	/* Zeroing the unused blocks on this cluster */
-	while (blknr < last_blknr) {
-		for (n = 0; n < nr_bhs && blknr < last_blknr; n++, blknr++) {
-			bhs[n] = sb_getblk(sb, blknr);
-			if (!bhs[n]) {
-				err = -ENOMEM;
-				goto release_bhs;
-			}
-			memset(bhs[n]->b_data, 0, sb->s_blocksize);
-		}
-
-		err = exfat_update_bhs(bhs, n, IS_DIRSYNC(dir));
-		if (err)
-			goto release_bhs;
+	for (i = blknr; i < last_blknr; i++) {
+		bh = sb_getblk(sb, i);
+		if (!bh)
+			return -ENOMEM;
 
-		for (i = 0; i < n; i++)
-			brelse(bhs[i]);
+		memset(bh->b_data, 0, sb->s_blocksize);
+		set_buffer_uptodate(bh);
+		mark_buffer_dirty(bh);
+		brelse(bh);
 	}
-	return 0;
 
-release_bhs:
-	exfat_err(sb, "failed zeroed sect %llu\n", (unsigned long long)blknr);
-	for (i = 0; i < n; i++)
-		bforget(bhs[i]);
-	return err;
+	if (IS_DIRSYNC(dir))
+		return sync_blockdev_range(sb->s_bdev,
+				EXFAT_BLK_TO_B(blknr, sb),
+				EXFAT_BLK_TO_B(last_blknr, sb) - 1);
+
+	return 0;
 }
 
 int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc,
diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
index d5bd8e6d9741..9380e0188b55 100644
--- a/fs/exfat/misc.c
+++ b/fs/exfat/misc.c
@@ -74,6 +74,13 @@ static void exfat_adjust_tz(struct timespec64 *ts, u8 tz_off)
 		ts->tv_sec += TIMEZONE_SEC(0x80 - tz_off);
 }
 
+static inline int exfat_tz_offset(struct exfat_sb_info *sbi)
+{
+	if (sbi->options.sys_tz)
+		return -sys_tz.tz_minuteswest;
+	return sbi->options.time_offset;
+}
+
 /* Convert a EXFAT time/date pair to a UNIX date (seconds since 1 1 70). */
 void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
 		u8 tz, __le16 time, __le16 date, u8 time_cs)
@@ -96,8 +103,7 @@ void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
 		/* Adjust timezone to UTC0. */
 		exfat_adjust_tz(ts, tz & ~EXFAT_TZ_VALID);
 	else
-		/* Convert from local time to UTC using time_offset. */
-		ts->tv_sec -= sbi->options.time_offset * SECS_PER_MIN;
+		ts->tv_sec -= exfat_tz_offset(sbi) * SECS_PER_MIN;
 }
 
 /* Convert linear UNIX date to a EXFAT time/date pair. */
diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
index a02a04a993bf..76acc3721951 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/namei.c
@@ -1080,6 +1080,7 @@ static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
 
 		exfat_remove_entries(inode, p_dir, oldentry, 0,
 			num_old_entries);
+		ei->dir = *p_dir;
 		ei->entry = newentry;
 	} else {
 		if (exfat_get_entry_type(epold) == TYPE_FILE) {
@@ -1167,28 +1168,6 @@ static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
 	return 0;
 }
 
-static void exfat_update_parent_info(struct exfat_inode_info *ei,
-		struct inode *parent_inode)
-{
-	struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
-	struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
-	loff_t parent_isize = i_size_read(parent_inode);
-
-	/*
-	 * the problem that struct exfat_inode_info caches wrong parent info.
-	 *
-	 * because of flag-mismatch of ei->dir,
-	 * there is abnormal traversing cluster chain.
-	 */
-	if (unlikely(parent_ei->flags != ei->dir.flags ||
-		     parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
-		     parent_ei->start_clu != ei->dir.dir)) {
-		exfat_chain_set(&ei->dir, parent_ei->start_clu,
-			EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
-			parent_ei->flags);
-	}
-}
-
 /* rename or move a old file into a new file */
 static int __exfat_rename(struct inode *old_parent_inode,
 		struct exfat_inode_info *ei, struct inode *new_parent_inode,
@@ -1219,8 +1198,6 @@ static int __exfat_rename(struct inode *old_parent_inode,
 		return -ENOENT;
 	}
 
-	exfat_update_parent_info(ei, old_parent_inode);
-
 	exfat_chain_dup(&olddir, &ei->dir);
 	dentry = ei->entry;
 
@@ -1241,8 +1218,6 @@ static int __exfat_rename(struct inode *old_parent_inode,
 			goto out;
 		}
 
-		exfat_update_parent_info(new_ei, new_parent_inode);
-
 		p_dir = &(new_ei->dir);
 		new_entry = new_ei->entry;
 		ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh);
diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index be0788ecaf20..6a4dfe9f31ee 100644
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -170,7 +170,9 @@ static int exfat_show_options(struct seq_file *m, struct dentry *root)
 		seq_puts(m, ",discard");
 	if (opts->keep_last_dots)
 		seq_puts(m, ",keep_last_dots");
-	if (opts->time_offset)
+	if (opts->sys_tz)
+		seq_puts(m, ",sys_tz");
+	else if (opts->time_offset)
 		seq_printf(m, ",time_offset=%d", opts->time_offset);
 	return 0;
 }
@@ -214,6 +216,7 @@ enum {
 	Opt_errors,
 	Opt_discard,
 	Opt_keep_last_dots,
+	Opt_sys_tz,
 	Opt_time_offset,
 
 	/* Deprecated options */
@@ -241,6 +244,7 @@ static const struct fs_parameter_spec exfat_parameters[] = {
 	fsparam_enum("errors",			Opt_errors, exfat_param_enums),
 	fsparam_flag("discard",			Opt_discard),
 	fsparam_flag("keep_last_dots",		Opt_keep_last_dots),
+	fsparam_flag("sys_tz",			Opt_sys_tz),
 	fsparam_s32("time_offset",		Opt_time_offset),
 	__fsparam(NULL, "utf8",			Opt_utf8, fs_param_deprecated,
 		  NULL),
@@ -298,6 +302,9 @@ static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param)
 	case Opt_keep_last_dots:
 		opts->keep_last_dots = 1;
 		break;
+	case Opt_sys_tz:
+		opts->sys_tz = 1;
+		break;
 	case Opt_time_offset:
 		/*
 		 * Make the limit 24 just in case someone invents something