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-rw-r--r--fs/notify/fanotify/fanotify.c76
-rw-r--r--fs/notify/fanotify/fanotify.h40
-rw-r--r--fs/notify/fanotify/fanotify_user.c4
3 files changed, 108 insertions, 12 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index ef39664e389c..599654564b2a 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -53,6 +53,23 @@ static bool fanotify_fid_event_equal(struct fanotify_fid_event *ffe1,
fanotify_fh_equal(&ffe1->object_fh, &ffe2->object_fh);
}
+static bool fanotify_name_event_equal(struct fanotify_name_event *fne1,
+ struct fanotify_name_event *fne2)
+{
+ /*
+ * Do not merge name events without dir fh.
+ * FAN_DIR_MODIFY does not encode object fh, so it may be empty.
+ */
+ if (!fne1->dir_fh.len)
+ return false;
+
+ if (fne1->name_len != fne2->name_len ||
+ !fanotify_fh_equal(&fne1->dir_fh, &fne2->dir_fh))
+ return false;
+
+ return !memcmp(fne1->name, fne2->name, fne1->name_len);
+}
+
static bool should_merge(struct fsnotify_event *old_fsn,
struct fsnotify_event *new_fsn)
{
@@ -84,6 +101,9 @@ static bool should_merge(struct fsnotify_event *old_fsn,
return fanotify_fid_event_equal(FANOTIFY_FE(old),
FANOTIFY_FE(new));
+ case FANOTIFY_EVENT_TYPE_FID_NAME:
+ return fanotify_name_event_equal(FANOTIFY_NE(old),
+ FANOTIFY_NE(new));
default:
WARN_ON_ONCE(1);
}
@@ -262,6 +282,9 @@ static void fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode,
void *buf = fh->buf;
int err;
+ if (!inode)
+ goto out;
+
dwords = 0;
err = -ENOENT;
type = exportfs_encode_inode_fh(inode, NULL, &dwords, NULL);
@@ -295,6 +318,7 @@ out_err:
type, bytes, err);
kfree(ext_buf);
*fanotify_fh_ext_buf_ptr(fh) = NULL;
+out:
/* Report the event without a file identifier on encode error */
fh->type = FILEID_INVALID;
fh->len = 0;
@@ -320,10 +344,12 @@ static struct inode *fanotify_fid_inode(struct inode *to_tell, u32 event_mask,
struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
struct inode *inode, u32 mask,
const void *data, int data_type,
+ const struct qstr *file_name,
__kernel_fsid_t *fsid)
{
struct fanotify_event *event = NULL;
struct fanotify_fid_event *ffe = NULL;
+ struct fanotify_name_event *fne = NULL;
gfp_t gfp = GFP_KERNEL_ACCOUNT;
struct inode *id = fanotify_fid_inode(inode, mask, data, data_type);
const struct path *path = fsnotify_data_path(data, data_type);
@@ -356,6 +382,23 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
goto init;
}
+ /*
+ * For FAN_DIR_MODIFY event, we report the fid of the directory and
+ * the name of the modified entry.
+ * Allocate an fanotify_name_event struct and copy the name.
+ */
+ if (mask & FAN_DIR_MODIFY && !(WARN_ON_ONCE(!file_name))) {
+ fne = kmalloc(sizeof(*fne) + file_name->len + 1, gfp);
+ if (!fne)
+ goto out;
+
+ event = &fne->fae;
+ event->type = FANOTIFY_EVENT_TYPE_FID_NAME;
+ fne->name_len = file_name->len;
+ strcpy(fne->name, file_name->name);
+ goto init;
+ }
+
if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
ffe = kmem_cache_alloc(fanotify_fid_event_cachep, gfp);
if (!ffe)
@@ -374,7 +417,7 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
event->type = FANOTIFY_EVENT_TYPE_PATH;
}
-init: __maybe_unused
+init:
/*
* Use the victim inode instead of the watching inode as the id for
* event queue, so event reported on parent is merged with event
@@ -387,13 +430,16 @@ init: __maybe_unused
else
event->pid = get_pid(task_tgid(current));
- if (fanotify_event_object_fh(event)) {
- ffe->object_fh.len = 0;
- if (fsid)
- ffe->fsid = *fsid;
- if (id)
- fanotify_encode_fh(&ffe->object_fh, id, gfp);
- } else if (fanotify_event_has_path(event)) {
+ if (fsid && fanotify_event_fsid(event))
+ *fanotify_event_fsid(event) = *fsid;
+
+ if (fanotify_event_object_fh(event))
+ fanotify_encode_fh(fanotify_event_object_fh(event), id, gfp);
+
+ if (fanotify_event_dir_fh(event))
+ fanotify_encode_fh(fanotify_event_dir_fh(event), id, gfp);
+
+ if (fanotify_event_has_path(event)) {
struct path *p = fanotify_event_path(event);
if (path) {
@@ -501,7 +547,7 @@ static int fanotify_handle_event(struct fsnotify_group *group,
}
event = fanotify_alloc_event(group, inode, mask, data, data_type,
- &fsid);
+ file_name, &fsid);
ret = -ENOMEM;
if (unlikely(!event)) {
/*
@@ -563,6 +609,15 @@ static void fanotify_free_fid_event(struct fanotify_event *event)
kmem_cache_free(fanotify_fid_event_cachep, ffe);
}
+static void fanotify_free_name_event(struct fanotify_event *event)
+{
+ struct fanotify_name_event *fne = FANOTIFY_NE(event);
+
+ if (fanotify_fh_has_ext_buf(&fne->dir_fh))
+ kfree(fanotify_fh_ext_buf(&fne->dir_fh));
+ kfree(fne);
+}
+
static void fanotify_free_event(struct fsnotify_event *fsn_event)
{
struct fanotify_event *event;
@@ -579,6 +634,9 @@ static void fanotify_free_event(struct fsnotify_event *fsn_event)
case FANOTIFY_EVENT_TYPE_FID:
fanotify_free_fid_event(event);
break;
+ case FANOTIFY_EVENT_TYPE_FID_NAME:
+ fanotify_free_name_event(event);
+ break;
default:
WARN_ON_ONCE(1);
}
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index eecf4be3bfd1..35bfbf4a7aac 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -59,7 +59,8 @@ static inline void *fanotify_fh_buf(struct fanotify_fh *fh)
* be freed and which concrete struct it may be cast to.
*/
enum fanotify_event_type {
- FANOTIFY_EVENT_TYPE_FID,
+ FANOTIFY_EVENT_TYPE_FID, /* fixed length */
+ FANOTIFY_EVENT_TYPE_FID_NAME, /* variable length */
FANOTIFY_EVENT_TYPE_PATH,
FANOTIFY_EVENT_TYPE_PATH_PERM,
};
@@ -83,10 +84,26 @@ FANOTIFY_FE(struct fanotify_event *event)
return container_of(event, struct fanotify_fid_event, fae);
}
+struct fanotify_name_event {
+ struct fanotify_event fae;
+ __kernel_fsid_t fsid;
+ struct fanotify_fh dir_fh;
+ u8 name_len;
+ char name[0];
+};
+
+static inline struct fanotify_name_event *
+FANOTIFY_NE(struct fanotify_event *event)
+{
+ return container_of(event, struct fanotify_name_event, fae);
+}
+
static inline __kernel_fsid_t *fanotify_event_fsid(struct fanotify_event *event)
{
if (event->type == FANOTIFY_EVENT_TYPE_FID)
return &FANOTIFY_FE(event)->fsid;
+ else if (event->type == FANOTIFY_EVENT_TYPE_FID_NAME)
+ return &FANOTIFY_NE(event)->fsid;
else
return NULL;
}
@@ -100,6 +117,15 @@ static inline struct fanotify_fh *fanotify_event_object_fh(
return NULL;
}
+static inline struct fanotify_fh *fanotify_event_dir_fh(
+ struct fanotify_event *event)
+{
+ if (event->type == FANOTIFY_EVENT_TYPE_FID_NAME)
+ return &FANOTIFY_NE(event)->dir_fh;
+ else
+ return NULL;
+}
+
static inline int fanotify_event_object_fh_len(struct fanotify_event *event)
{
struct fanotify_fh *fh = fanotify_event_object_fh(event);
@@ -107,6 +133,17 @@ static inline int fanotify_event_object_fh_len(struct fanotify_event *event)
return fh ? fh->len : 0;
}
+static inline bool fanotify_event_has_name(struct fanotify_event *event)
+{
+ return event->type == FANOTIFY_EVENT_TYPE_FID_NAME;
+}
+
+static inline int fanotify_event_name_len(struct fanotify_event *event)
+{
+ return fanotify_event_has_name(event) ?
+ FANOTIFY_NE(event)->name_len : 0;
+}
+
struct fanotify_path_event {
struct fanotify_event fae;
struct path path;
@@ -169,4 +206,5 @@ static inline struct path *fanotify_event_path(struct fanotify_event *event)
struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
struct inode *inode, u32 mask,
const void *data, int data_type,
+ const struct qstr *file_name,
__kernel_fsid_t *fsid);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index b93585406aad..a9d287a56098 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -210,7 +210,7 @@ static int copy_fid_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh,
struct fanotify_event_info_fid info = { };
struct file_handle handle = { };
unsigned char bounce[FANOTIFY_INLINE_FH_LEN], *fh_buf;
- size_t fh_len = fh->len;
+ size_t fh_len = fh ? fh->len : 0;
size_t len = fanotify_fid_info_len(fh_len);
if (!len)
@@ -828,7 +828,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
group->memcg = get_mem_cgroup_from_mm(current->mm);
oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL,
- FSNOTIFY_EVENT_NONE, NULL);
+ FSNOTIFY_EVENT_NONE, NULL, NULL);
if (unlikely(!oevent)) {
fd = -ENOMEM;
goto out_destroy_group;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 18:57:10 +0000