[PATCH v2] f2fs: check validation of fault attrs in f2fs_build_fault_attr()

[Chao Yu]

- It missed to check validation of fault attrs in parse_options(),
let's fix to add check condition in f2fs_build_fault_attr().
- Use f2fs_build_fault_attr() in __sbi_store() to clean up code.

Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
v2:
- add static for f2fs_build_fault_attr().
 fs/f2fs/f2fs.h  | 12 ++++++++----
 fs/f2fs/super.c | 27 ++++++++++++++++++++-------
 fs/f2fs/sysfs.c | 14 ++++++++++----
 3 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 95a40d4f778f..a29576f46796 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -72,7 +72,7 @@ enum {
 
 struct f2fs_fault_info {
 	atomic_t inject_ops;
-	unsigned int inject_rate;
+	int inject_rate;
 	unsigned int inject_type;
 };
 
@@ -4597,10 +4597,14 @@ static inline bool f2fs_need_verity(const struct inode *inode, pgoff_t idx)
 }
 
 #ifdef CONFIG_F2FS_FAULT_INJECTION
-extern void f2fs_build_fault_attr(struct f2fs_sb_info *sbi, unsigned int rate,
-							unsigned int type);
+extern int f2fs_build_fault_attr(struct f2fs_sb_info *sbi, unsigned long rate,
+							unsigned long type);
 #else
-#define f2fs_build_fault_attr(sbi, rate, type)		do { } while (0)
+static int f2fs_build_fault_attr(struct f2fs_sb_info *sbi, unsigned long rate,
+							unsigned long type)
+{
+	return 0;
+}
 #endif
 
 static inline bool is_journalled_quota(struct f2fs_sb_info *sbi)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index a4bc26dfdb1a..94918ae7eddb 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -66,21 +66,31 @@ const char *f2fs_fault_name[FAULT_MAX] = {
 	[FAULT_NO_SEGMENT]		= "no free segment",
 };
 
-void f2fs_build_fault_attr(struct f2fs_sb_info *sbi, unsigned int rate,
-							unsigned int type)
+int f2fs_build_fault_attr(struct f2fs_sb_info *sbi, unsigned long rate,
+							unsigned long type)
 {
 	struct f2fs_fault_info *ffi = &F2FS_OPTION(sbi).fault_info;
 
 	if (rate) {
+		if (rate > INT_MAX)
+			return -EINVAL;
 		atomic_set(&ffi->inject_ops, 0);
-		ffi->inject_rate = rate;
+		ffi->inject_rate = (int)rate;
 	}
 
-	if (type)
-		ffi->inject_type = type;
+	if (type) {
+		if (type >= BIT(FAULT_MAX))
+			return -EINVAL;
+		ffi->inject_type = (unsigned int)type;
+	}
 
 	if (!rate && !type)
 		memset(ffi, 0, sizeof(struct f2fs_fault_info));
+	else
+		f2fs_info(sbi,
+			"build fault injection attr: rate: %lu, type: 0x%lx",
+								rate, type);
+	return 0;
 }
 #endif
 
@@ -886,14 +896,17 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
 		case Opt_fault_injection:
 			if (args->from && match_int(args, &arg))
 				return -EINVAL;
-			f2fs_build_fault_attr(sbi, arg, F2FS_ALL_FAULT_TYPE);
+			if (f2fs_build_fault_attr(sbi, arg,
+					F2FS_ALL_FAULT_TYPE))
+				return -EINVAL;
 			set_opt(sbi, FAULT_INJECTION);
 			break;
 
 		case Opt_fault_type:
 			if (args->from && match_int(args, &arg))
 				return -EINVAL;
-			f2fs_build_fault_attr(sbi, 0, arg);
+			if (f2fs_build_fault_attr(sbi, 0, arg))
+				return -EINVAL;
 			set_opt(sbi, FAULT_INJECTION);
 			break;
 #else
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index a568ce96cf56..7aa3844e7a80 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -484,10 +484,16 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
 	if (ret < 0)
 		return ret;
 #ifdef CONFIG_F2FS_FAULT_INJECTION
-	if (a->struct_type == FAULT_INFO_TYPE && t >= BIT(FAULT_MAX))
-		return -EINVAL;
-	if (a->struct_type == FAULT_INFO_RATE && t >= UINT_MAX)
-		return -EINVAL;
+	if (a->struct_type == FAULT_INFO_TYPE) {
+		if (f2fs_build_fault_attr(sbi, 0, t))
+			return -EINVAL;
+		return count;
+	}
+	if (a->struct_type == FAULT_INFO_RATE) {
+		if (f2fs_build_fault_attr(sbi, t, 0))
+			return -EINVAL;
+		return count;
+	}
 #endif
 	if (a->struct_type == RESERVED_BLOCKS) {
 		spin_lock(&sbi->stat_lock);
-- 
2.40.1