fsync¶

Intro¶

fsync - synchronizes a file's in-memory state with the physical storage device

Description¶

The fsync function is a system call that is used to flush, or synchronize, the in-memory state of a file with the device containing the file. This is useful for ensuring that important data is not lost in the case of a system crash or loss of power. The fsync call ensures that the contents of the file, as well as associated data structures (such as the inode) are correctly written out to the device before the call returns. It is also used when programs want to be sure that their changes have been written back to the device.

One of the drawbacks of using fsync is that it can be computationally expensive as it must ensure that all of the relevant data structures are correctly written out to the device.

Arguments¶

fd:int[K] - file descriptor of the file to be synchronized with the device.

Available Tags¶

K - Originated from kernel-space.

Hooks¶

sys_fsync¶

Type¶

kprobe + prof

Purpose¶

To track the invocation of the fsync syscall and evaluate its impact on performance or system resources.

Example Use Case¶

fsync could be used when a user wants to make sure that the changes they have made to a file have been written to the device before they do something else with the file.

Issues¶

Some systems can be vulnerable to a Resource Attack when fsync is used. This can occur if an attacker is able to send a large number of requests which trigger the fsync call.

open - used to open a file descriptor for use with fsync.
close - used to close the file descriptor after the fsync call has been completed.

This document was automatically generated by OpenAI and needs review. It might not be accurate and might contain errors. The authors of Tracee recommend that the user reads the "events.go" source file to understand the events and their arguments better.