[PATCH v4 2/5] fs: Check if utf8 encoding is loaded before calling utf8_unload()

From: Shreeya Patel
Date: Wed Mar 24 2021 - 20:09:23 EST


utf8_unload is being called if CONFIG_UNICODE is enabled.
The ifdef block doesn't check if utf8 encoding has been loaded
or not before calling the utf8_unload() function.
This is not the expected behavior since it would sometimes lead
to unloading utf8 even before loading it.
Hence, add a condition which will check if sb->encoding is NOT NULL
before calling the utf8_unload().

Reviewed-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
Signed-off-by: Shreeya Patel <shreeya.patel@xxxxxxxxxxxxx>
---
fs/ext4/super.c | 6 ++++--
fs/f2fs/super.c | 9 ++++++---
2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index ad34a37278cd..e438d14f9a87 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1259,7 +1259,8 @@ static void ext4_put_super(struct super_block *sb)
fs_put_dax(sbi->s_daxdev);
fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
#ifdef CONFIG_UNICODE
- utf8_unload(sb->s_encoding);
+ if (sb->s_encoding)
+ utf8_unload(sb->s_encoding);
#endif
kfree(sbi);
}
@@ -5165,7 +5166,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
crypto_free_shash(sbi->s_chksum_driver);

#ifdef CONFIG_UNICODE
- utf8_unload(sb->s_encoding);
+ if (sb->s_encoding)
+ utf8_unload(sb->s_encoding);
#endif

#ifdef CONFIG_QUOTA
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 7069793752f1..0a04983c294e 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1430,7 +1430,8 @@ static void f2fs_put_super(struct super_block *sb)
for (i = 0; i < NR_PAGE_TYPE; i++)
kvfree(sbi->write_io[i]);
#ifdef CONFIG_UNICODE
- utf8_unload(sb->s_encoding);
+ if (sb->s_encoding)
+ utf8_unload(sb->s_encoding);
#endif
kfree(sbi);
}
@@ -4073,8 +4074,10 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
kvfree(sbi->write_io[i]);

#ifdef CONFIG_UNICODE
- utf8_unload(sb->s_encoding);
- sb->s_encoding = NULL;
+ if (sb->s_encoding) {
+ utf8_unload(sb->s_encoding);
+ sb->s_encoding = NULL;
+ }
#endif
free_options:
#ifdef CONFIG_QUOTA
--
2.30.1