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-rw-r--r--fs/notify/fanotify/fanotify.c2
-rw-r--r--fs/notify/fanotify/fanotify.h41
2 files changed, 31 insertions, 12 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 85e542b164c8..ffad224be014 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -411,7 +411,7 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode,
* be zero in that case if encoding fh len failed.
*/
err = -ENOENT;
- if (fh_len < 4 || WARN_ON_ONCE(fh_len % 4))
+ if (fh_len < 4 || WARN_ON_ONCE(fh_len % 4) || fh_len > MAX_HANDLE_SZ)
goto out_err;
/* No external buffer in a variable size allocated fh */
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index d25f500bf7e7..dd23ba659e76 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -49,6 +49,22 @@ struct fanotify_info {
* (optional) file_fh starts at buf[dir_fh_totlen]
* name starts at buf[dir_fh_totlen + file_fh_totlen]
*/
+#define FANOTIFY_DIR_FH_SIZE(info) ((info)->dir_fh_totlen)
+#define FANOTIFY_FILE_FH_SIZE(info) ((info)->file_fh_totlen)
+#define FANOTIFY_NAME_SIZE(info) ((info)->name_len + 1)
+
+#define FANOTIFY_DIR_FH_OFFSET(info) 0
+#define FANOTIFY_FILE_FH_OFFSET(info) \
+ (FANOTIFY_DIR_FH_OFFSET(info) + FANOTIFY_DIR_FH_SIZE(info))
+#define FANOTIFY_NAME_OFFSET(info) \
+ (FANOTIFY_FILE_FH_OFFSET(info) + FANOTIFY_FILE_FH_SIZE(info))
+
+#define FANOTIFY_DIR_FH_BUF(info) \
+ ((info)->buf + FANOTIFY_DIR_FH_OFFSET(info))
+#define FANOTIFY_FILE_FH_BUF(info) \
+ ((info)->buf + FANOTIFY_FILE_FH_OFFSET(info))
+#define FANOTIFY_NAME_BUF(info) \
+ ((info)->buf + FANOTIFY_NAME_OFFSET(info))
} __aligned(4);
static inline bool fanotify_fh_has_ext_buf(struct fanotify_fh *fh)
@@ -87,7 +103,7 @@ static inline struct fanotify_fh *fanotify_info_dir_fh(struct fanotify_info *inf
{
BUILD_BUG_ON(offsetof(struct fanotify_info, buf) % 4);
- return (struct fanotify_fh *)info->buf;
+ return (struct fanotify_fh *)FANOTIFY_DIR_FH_BUF(info);
}
static inline int fanotify_info_file_fh_len(struct fanotify_info *info)
@@ -101,32 +117,35 @@ static inline int fanotify_info_file_fh_len(struct fanotify_info *info)
static inline struct fanotify_fh *fanotify_info_file_fh(struct fanotify_info *info)
{
- return (struct fanotify_fh *)(info->buf + info->dir_fh_totlen);
+ return (struct fanotify_fh *)FANOTIFY_FILE_FH_BUF(info);
}
-static inline const char *fanotify_info_name(struct fanotify_info *info)
+static inline char *fanotify_info_name(struct fanotify_info *info)
{
- return info->buf + info->dir_fh_totlen + info->file_fh_totlen;
+ if (!info->name_len)
+ return NULL;
+
+ return FANOTIFY_NAME_BUF(info);
}
static inline void fanotify_info_init(struct fanotify_info *info)
{
+ BUILD_BUG_ON(FANOTIFY_FH_HDR_LEN + MAX_HANDLE_SZ > U8_MAX);
+ BUILD_BUG_ON(NAME_MAX > U8_MAX);
+
info->dir_fh_totlen = 0;
info->file_fh_totlen = 0;
info->name_len = 0;
}
-static inline unsigned int fanotify_info_len(struct fanotify_info *info)
-{
- return info->dir_fh_totlen + info->file_fh_totlen + info->name_len;
-}
-
static inline void fanotify_info_copy_name(struct fanotify_info *info,
const struct qstr *name)
{
+ if (WARN_ON_ONCE(name->len > NAME_MAX))
+ return;
+
info->name_len = name->len;
- strcpy(info->buf + info->dir_fh_totlen + info->file_fh_totlen,
- name->name);
+ strcpy(fanotify_info_name(info), name->name);
}
/*