From 949f4a7c08bc4a050eae7aeeac3e6d019d1feafb Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 20 Oct 2010 18:49:20 +0200 Subject: udf: Protect all modifications of LVID with s_alloc_mutex udf_open_lvid() and udf_close_lvid() were modifying LVID without s_alloc_mutex. Since they can be called from remount, the modification could race with other filesystem modifications of LVID so protect them by s_alloc_mutex just to be sure. Signed-off-by: Jan Kara --- fs/udf/super.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/udf') diff --git a/fs/udf/super.c b/fs/udf/super.c index 948e1aca0f34..e54960c0e960 100644 --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -1773,6 +1773,8 @@ static void udf_open_lvid(struct super_block *sb) if (!bh) return; + + mutex_lock(&sbi->s_alloc_mutex); lvid = (struct logicalVolIntegrityDesc *)bh->b_data; lvidiu = udf_sb_lvidiu(sbi); @@ -1789,6 +1791,7 @@ static void udf_open_lvid(struct super_block *sb) lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag); mark_buffer_dirty(bh); sbi->s_lvid_dirty = 0; + mutex_unlock(&sbi->s_alloc_mutex); } static void udf_close_lvid(struct super_block *sb) @@ -1801,6 +1804,7 @@ static void udf_close_lvid(struct super_block *sb) if (!bh) return; + mutex_lock(&sbi->s_alloc_mutex); lvid = (struct logicalVolIntegrityDesc *)bh->b_data; lvidiu = udf_sb_lvidiu(sbi); lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX; @@ -1821,6 +1825,7 @@ static void udf_close_lvid(struct super_block *sb) lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag); mark_buffer_dirty(bh); sbi->s_lvid_dirty = 0; + mutex_unlock(&sbi->s_alloc_mutex); } u64 lvid_get_unique_id(struct super_block *sb) -- cgit