kernel/linux.git/include/linux/file.h, branch v6.6.132

locking: Introduce __cleanup() based infrastructure

2023-06-26T09:14:18+00:00

Use __attribute__((__cleanup__(func))) to build: - simple auto-release pointers using __free() - 'classes' with constructor and destructor semantics for scope-based resource management. - lock guards based on the above classes. Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org

fs: remove fget_many and fput_many interface

2022-05-14T22:47:28+00:00

These two interface were added in 091141a42 commit, but now there is no place to call them. The only user of fput/fget_many() was removed in commit 62906e89e63b ("io_uring: remove file batch-get optimisation"). A user of get_file_rcu_many() were removed in commit f073531070d2 ("init: add an init_dup helper"). And replace atomic_long_sub/add to atomic_long_dec/inc can improve performance. Here are the test results of unixbench: Cmd: ./Run -c 64 context1 Without patch: System Benchmarks Partial Index BASELINE RESULT INDEX Pipe-based Context Switching 4000.0 2798407.0 6996.0 ======== System Benchmarks Index Score (Partial Only) 6996.0 With patch: System Benchmarks Partial Index BASELINE RESULT INDEX Pipe-based Context Switching 4000.0 3486268.8 8715.7 ======== System Benchmarks Index Score (Partial Only) 8715.7 Signed-off-by: Gou Hao Signed-off-by: Al Viro

file: Export receive_fd() to modules

2021-09-06T11:20:56+00:00

Export receive_fd() so that some modules can use it to pass file descriptor between processes without missing any security stuffs. Signed-off-by: Xie Yongji Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210831103634.33-4-xieyongji@bytedance.com Signed-off-by: Michael S. Tsirkin

fs: split receive_fd_replace from __receive_fd

2021-04-16T04:13:04+00:00

receive_fd_replace shares almost no code with the general case, so split it out. Also remove the "Bump the sock usage counts" comment from both copies, as that is now what __receive_sock actually does. [AV: ... and make the only user of receive_fd_replace() choose between it and receive_fd() according to what userland had passed to it in flags] Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro

fs: Expand __receive_fd() to accept existing fd

2020-07-13T18:03:45+00:00

Expand __receive_fd() with support for replace_fd() for the coming seccomp "addfd" ioctl(). Add new wrapper receive_fd_replace() for the new behavior and update existing wrappers to retain old behavior. Thanks to Colin Ian King for pointing out an uninitialized variable exposure in an earlier version of this patch. Cc: Alexander Viro Cc: Dmitry Kadashev Cc: Jens Axboe Cc: Arnd Bergmann Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Sargun Dhillon Acked-by: Christian Brauner Signed-off-by: Kees Cook

fs: Add receive_fd() wrapper for __receive_fd()

2020-07-13T18:03:44+00:00

For both pidfd and seccomp, the __user pointer is not used. Update __receive_fd() to make writing to ufd optional via a NULL check. However, for the receive_fd_user() wrapper, ufd is NULL checked so an -EFAULT can be returned to avoid changing the SCM_RIGHTS interface behavior. Add new wrapper receive_fd() for pidfd and seccomp that does not use the ufd argument. For the new helper, the allocated fd needs to be returned on success. Update the existing callers to handle it. Cc: Alexander Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Sargun Dhillon Acked-by: Christian Brauner Signed-off-by: Kees Cook

fs: Move __scm_install_fd() to __receive_fd()

2020-07-13T18:03:44+00:00

In preparation for users of the "install a received file" logic outside of net/ (pidfd and seccomp), relocate and rename __scm_install_fd() from net/core/scm.c to __receive_fd() in fs/file.c, and provide a wrapper named receive_fd_user(), as future patches will change the interface to __receive_fd(). Additionally add a comment to fd_install() as a counterpoint to how __receive_fd() interacts with fput(). Cc: Alexander Viro Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Dmitry Kadashev Cc: Jens Axboe Cc: Arnd Bergmann Cc: Sargun Dhillon Cc: Ido Schimmel Cc: Ioana Ciornei Cc: linux-fsdevel@vger.kernel.org Cc: netdev@vger.kernel.org Reviewed-by: Sargun Dhillon Acked-by: Christian Brauner Signed-off-by: Kees Cook

sysctl: remove all extern declaration from sysctl.c

2020-04-27T06:06:53+00:00

Extern declarations in .c files are a bad style and can lead to mismatches. Use existing definitions in headers where they exist, and otherwise move the external declarations to suitable header files. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro

io_uring: make sure openat/openat2 honor rlimit nofile

2020-03-20T14:47:27+00:00

Dmitry reports that a test case shows that io_uring isn't honoring a modified rlimit nofile setting. get_unused_fd_flags() checks the task signal->rlimi[] for the limits. As this isn't easily inheritable, provide a __get_unused_fd_flags() that takes the value instead. Then we can grab it when the request is prepared (from the original task), and pass that in when we do the async part part of the open. Reported-by: Dmitry Kadashev Tested-by: Dmitry Kadashev Acked-by: David S. Miller Signed-off-by: Jens Axboe

vfs, fdtable: Add fget_task helper

2020-01-13T20:48:42+00:00

This introduces a function which can be used to fetch a file, given an arbitrary task. As long as the user holds a reference (refcnt) to the task_struct it is safe to call, and will either return NULL on failure, or a pointer to the file, with a refcnt. This patch is based on Oleg Nesterov's (cf. [1]) patch from September 2018. [1]: Link: https://lore.kernel.org/r/20180915160423.GA31461@redhat.com Signed-off-by: Sargun Dhillon Suggested-by: Oleg Nesterov Acked-by: Christian Brauner Reviewed-by: Arnd Bergmann Link: https://lore.kernel.org/r/20200107175927.4558-2-sargun@sargun.me Signed-off-by: Christian Brauner