This patch introduces an optional info record that describes the
source (as in the region of the source-code where an event was
initiated). This record is not produced for other type of existing
notification, but it is optionally enabled for FAN_ERROR notifications.
Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
---
fs/notify/fanotify/fanotify.h | 6 +++++
fs/notify/fanotify/fanotify_user.c | 35 ++++++++++++++++++++++++++++++
include/uapi/linux/fanotify.h | 7 ++++++
3 files changed, 48 insertions(+)
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index 4cb9dd31f084..0d1b4cb8b005 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -161,6 +161,11 @@ struct fanotify_fid_event {
unsigned char _inline_fh_buf[FANOTIFY_INLINE_FH_LEN];
};
+struct fanotify_event_location {
+ int line;
+ const char *function;
+};
+
static inline struct fanotify_fid_event *
FANOTIFY_FE(struct fanotify_event *event)
{
@@ -183,6 +188,7 @@ struct fanotify_error_event {
struct fanotify_event fae;
int error;
__kernel_fsid_t fsid;
+ struct fanotify_event_location loc;
int fs_data_size;
/* Must be the last item in the structure */
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 21162d347bd1..cb79a4a8e6fb 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -69,6 +69,16 @@ static size_t fanotify_error_info_len(struct fanotify_error_event *fee)
return sizeof(struct fanotify_event_info_error);
}
+static size_t fanotify_location_info_len(const struct fanotify_event_location *loc)
+{
+ if (!loc->function)
+ return 0;
+
+ /* Includes NULL byte at end of loc->function */
+ return (sizeof(struct fanotify_event_info_location) +
+ strlen(loc->function) + 1);
+}
+
static size_t fanotify_event_len(struct fanotify_event *event,
unsigned int fid_mode)
{
@@ -260,6 +270,31 @@ static size_t copy_error_info_to_user(struct fanotify_error_event *fee,
}
+static size_t copy_location_info_to_user(struct fanotify_event_location *location,
+ char __user *buf, int count)
+{
+ size_t len = fanotify_location_info_len(location);
+ size_t tail = len - sizeof(struct fanotify_event_info_location);
+ struct fanotify_event_info_location info;
+
+ if (!len)
+ return 0;
+
+ info.hdr.info_type = FAN_EVENT_INFO_TYPE_LOCATION;
+ info.hdr.len = len;
+ info.line = location->line;
+
+ if (copy_to_user(buf, &info, sizeof(info)))
+ return -EFAULT;
+
+ buf += sizeof(info);
+
+ if (copy_to_user(buf, location->function, tail))
+ return -EFAULT;
+
+ return info.hdr.len;
+}
+
static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh,
int info_type, const char *name, size_t name_len,
char __user *buf, size_t count)
diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h
index cc9a1fa80e30..67217756dac9 100644
--- a/include/uapi/linux/fanotify.h
+++ b/include/uapi/linux/fanotify.h
@@ -125,6 +125,7 @@ struct fanotify_event_metadata {
#define FAN_EVENT_INFO_TYPE_DFID_NAME 2
#define FAN_EVENT_INFO_TYPE_DFID 3
#define FAN_EVENT_INFO_TYPE_ERROR 4
+#define FAN_EVENT_INFO_TYPE_LOCATION 5
/* Variable length info record following event metadata */
struct fanotify_event_info_header {
@@ -159,6 +160,12 @@ struct fanotify_event_info_error {
__kernel_fsid_t fsid;
};
+struct fanotify_event_info_location {
+ struct fanotify_event_info_header hdr;
+ int line;
+ char function[0];
+};
+
struct fanotify_response {
__s32 fd;
__u32 response;
--
2.31.0
