From 3cf984e950c1c3f41d407ed31db33beb996be132 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Mon, 29 Nov 2021 22:15:33 +0200 Subject: [PATCH] fanotify: support secondary dir fh and name in fanotify_info Allow storing a secondary dir fh and name tupple in fanotify_info. This will be used to store the new parent and name information in FAN_RENAME event. Link: https://lore.kernel.org/r/20211129201537.1932819-8-amir73il@gmail.com Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara --- fs/notify/fanotify/fanotify.c | 20 ++++++++-- fs/notify/fanotify/fanotify.h | 79 ++++++++++++++++++++++++++++++++++---- fs/notify/fanotify/fanotify_user.c | 3 +- 3 files changed, 88 insertions(+), 14 deletions(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 2b13c79..5f184b2 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -76,8 +76,10 @@ static bool fanotify_info_equal(struct fanotify_info *info1, struct fanotify_info *info2) { if (info1->dir_fh_totlen != info2->dir_fh_totlen || + info1->dir2_fh_totlen != info2->dir2_fh_totlen || info1->file_fh_totlen != info2->file_fh_totlen || - info1->name_len != info2->name_len) + info1->name_len != info2->name_len || + info1->name2_len != info2->name2_len) return false; if (info1->dir_fh_totlen && @@ -85,14 +87,24 @@ static bool fanotify_info_equal(struct fanotify_info *info1, fanotify_info_dir_fh(info2))) return false; + if (info1->dir2_fh_totlen && + !fanotify_fh_equal(fanotify_info_dir2_fh(info1), + fanotify_info_dir2_fh(info2))) + return false; + if (info1->file_fh_totlen && !fanotify_fh_equal(fanotify_info_file_fh(info1), fanotify_info_file_fh(info2))) return false; - return !info1->name_len || - !memcmp(fanotify_info_name(info1), fanotify_info_name(info2), - info1->name_len); + if (info1->name_len && + memcmp(fanotify_info_name(info1), fanotify_info_name(info2), + info1->name_len)) + return false; + + return !info1->name2_len || + !memcmp(fanotify_info_name2(info1), fanotify_info_name2(info2), + info1->name2_len); } static bool fanotify_name_event_equal(struct fanotify_name_event *fne1, diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 7ac6f9f..8fa3bc0 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -40,31 +40,45 @@ struct fanotify_fh { struct fanotify_info { /* size of dir_fh/file_fh including fanotify_fh hdr size */ u8 dir_fh_totlen; + u8 dir2_fh_totlen; u8 file_fh_totlen; u8 name_len; - u8 pad; + u8 name2_len; + u8 pad[3]; unsigned char buf[]; /* * (struct fanotify_fh) dir_fh starts at buf[0] - * (optional) file_fh starts at buf[dir_fh_totlen] - * name starts at buf[dir_fh_totlen + file_fh_totlen] + * (optional) dir2_fh starts at buf[dir_fh_totlen] + * (optional) file_fh starts at buf[dir_fh_totlen + dir2_fh_totlen] + * name starts at buf[dir_fh_totlen + dir2_fh_totlen + file_fh_totlen] + * ... */ #define FANOTIFY_DIR_FH_SIZE(info) ((info)->dir_fh_totlen) +#define FANOTIFY_DIR2_FH_SIZE(info) ((info)->dir2_fh_totlen) #define FANOTIFY_FILE_FH_SIZE(info) ((info)->file_fh_totlen) #define FANOTIFY_NAME_SIZE(info) ((info)->name_len + 1) +#define FANOTIFY_NAME2_SIZE(info) ((info)->name2_len + 1) #define FANOTIFY_DIR_FH_OFFSET(info) 0 -#define FANOTIFY_FILE_FH_OFFSET(info) \ +#define FANOTIFY_DIR2_FH_OFFSET(info) \ (FANOTIFY_DIR_FH_OFFSET(info) + FANOTIFY_DIR_FH_SIZE(info)) +#define FANOTIFY_FILE_FH_OFFSET(info) \ + (FANOTIFY_DIR2_FH_OFFSET(info) + FANOTIFY_DIR2_FH_SIZE(info)) #define FANOTIFY_NAME_OFFSET(info) \ (FANOTIFY_FILE_FH_OFFSET(info) + FANOTIFY_FILE_FH_SIZE(info)) +#define FANOTIFY_NAME2_OFFSET(info) \ + (FANOTIFY_NAME_OFFSET(info) + FANOTIFY_NAME_SIZE(info)) #define FANOTIFY_DIR_FH_BUF(info) \ ((info)->buf + FANOTIFY_DIR_FH_OFFSET(info)) +#define FANOTIFY_DIR2_FH_BUF(info) \ + ((info)->buf + FANOTIFY_DIR2_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)) +#define FANOTIFY_NAME2_BUF(info) \ + ((info)->buf + FANOTIFY_NAME2_OFFSET(info)) } __aligned(4); static inline bool fanotify_fh_has_ext_buf(struct fanotify_fh *fh) @@ -106,6 +120,20 @@ static inline struct fanotify_fh *fanotify_info_dir_fh(struct fanotify_info *inf return (struct fanotify_fh *)FANOTIFY_DIR_FH_BUF(info); } +static inline int fanotify_info_dir2_fh_len(struct fanotify_info *info) +{ + if (!info->dir2_fh_totlen || + WARN_ON_ONCE(info->dir2_fh_totlen < FANOTIFY_FH_HDR_LEN)) + return 0; + + return info->dir2_fh_totlen - FANOTIFY_FH_HDR_LEN; +} + +static inline struct fanotify_fh *fanotify_info_dir2_fh(struct fanotify_info *info) +{ + return (struct fanotify_fh *)FANOTIFY_DIR2_FH_BUF(info); +} + static inline int fanotify_info_file_fh_len(struct fanotify_info *info) { if (!info->file_fh_totlen || @@ -128,31 +156,55 @@ static inline char *fanotify_info_name(struct fanotify_info *info) return FANOTIFY_NAME_BUF(info); } +static inline char *fanotify_info_name2(struct fanotify_info *info) +{ + if (!info->name2_len) + return NULL; + + return FANOTIFY_NAME2_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->dir2_fh_totlen = 0; info->file_fh_totlen = 0; info->name_len = 0; + info->name2_len = 0; } /* These set/copy helpers MUST be called by order */ static inline void fanotify_info_set_dir_fh(struct fanotify_info *info, unsigned int totlen) { - if (WARN_ON_ONCE(info->file_fh_totlen > 0) || - WARN_ON_ONCE(info->name_len > 0)) + if (WARN_ON_ONCE(info->dir2_fh_totlen > 0) || + WARN_ON_ONCE(info->file_fh_totlen > 0) || + WARN_ON_ONCE(info->name_len > 0) || + WARN_ON_ONCE(info->name2_len > 0)) return; info->dir_fh_totlen = totlen; } +static inline void fanotify_info_set_dir2_fh(struct fanotify_info *info, + unsigned int totlen) +{ + if (WARN_ON_ONCE(info->file_fh_totlen > 0) || + WARN_ON_ONCE(info->name_len > 0) || + WARN_ON_ONCE(info->name2_len > 0)) + return; + + info->dir2_fh_totlen = totlen; +} + static inline void fanotify_info_set_file_fh(struct fanotify_info *info, unsigned int totlen) { - if (WARN_ON_ONCE(info->name_len > 0)) + if (WARN_ON_ONCE(info->name_len > 0) || + WARN_ON_ONCE(info->name2_len > 0)) return; info->file_fh_totlen = totlen; @@ -161,13 +213,24 @@ static inline void fanotify_info_set_file_fh(struct fanotify_info *info, static inline void fanotify_info_copy_name(struct fanotify_info *info, const struct qstr *name) { - if (WARN_ON_ONCE(name->len > NAME_MAX)) + if (WARN_ON_ONCE(name->len > NAME_MAX) || + WARN_ON_ONCE(info->name2_len > 0)) return; info->name_len = name->len; strcpy(fanotify_info_name(info), name->name); } +static inline void fanotify_info_copy_name2(struct fanotify_info *info, + const struct qstr *name) +{ + if (WARN_ON_ONCE(name->len > NAME_MAX)) + return; + + info->name2_len = name->len; + strcpy(fanotify_info_name2(info), name->name); +} + /* * Common structure for fanotify events. Concrete structs are allocated in * fanotify_handle_event() and freed when the information is retrieved by diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 00bbc29..e4a11f5 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -332,11 +332,10 @@ static int process_access_response(struct fsnotify_group *group, static size_t copy_error_info_to_user(struct fanotify_event *event, char __user *buf, int count) { - struct fanotify_event_info_error info; + struct fanotify_event_info_error info = { }; struct fanotify_error_event *fee = FANOTIFY_EE(event); info.hdr.info_type = FAN_EVENT_INFO_TYPE_ERROR; - info.hdr.pad = 0; info.hdr.len = FANOTIFY_ERROR_INFO_LEN; if (WARN_ON(count < info.hdr.len)) -- 2.7.4