kernel/linux.git/fs/efivarfs/file.c, branch linux-5.15.y

efivars: convert to fileattr

2021-04-12T13:04:29+00:00

Use the fileattr API to let the VFS handle locking, permission checking and conversion. Signed-off-by: Miklos Szeredi Cc: Matthew Garrett

inode: make init and permission helpers idmapped mount aware

2021-01-24T13:27:16+00:00

The inode_owner_or_capable() helper determines whether the caller is the owner of the inode or is capable with respect to that inode. Allow it to handle idmapped mounts. If the inode is accessed through an idmapped mount it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Similarly, allow the inode_init_owner() helper to handle idmapped mounts. It initializes a new inode on idmapped mounts by mapping the fsuid and fsgid of the caller from the mount's user namespace. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Reviewed-by: James Morris Signed-off-by: Christian Brauner

efivarfs: Don't return -EINTR when rate-limiting reads

2020-06-15T12:38:56+00:00

Applications that read EFI variables may see a return value of -EINTR if they exceed the rate limit and a signal delivery is attempted while the process is sleeping. This is quite surprising to the application, which probably doesn't have code to handle it. Change the interruptible sleep to a non-interruptible one. Reported-by: Lennart Poettering Signed-off-by: Tony Luck Link: https://lore.kernel.org/r/20200528194905.690-3-tony.luck@intel.com Signed-off-by: Ard Biesheuvel

efivarfs: Update inode modification time for successful writes

2020-06-15T12:38:56+00:00

Some applications want to be able to see when EFI variables have been updated. Update the modification time for successful writes. Reported-by: Lennart Poettering Signed-off-by: Tony Luck Link: https://lore.kernel.org/r/20200528194905.690-2-tony.luck@intel.com Signed-off-by: Ard Biesheuvel

Merge tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2019-07-12T23:54:37+00:00

Pull common SETFLAGS/FSSETXATTR parameter checking from Darrick Wong: "Here's a patch series that sets up common parameter checking functions for the FS_IOC_SETFLAGS and FS_IOC_FSSETXATTR ioctl implementations. The goal here is to reduce the amount of behaviorial variance between the filesystems where those ioctls originated (ext2 and XFS, respectively) and everybody else. - Standardize parameter checking for the SETFLAGS and FSSETXATTR ioctls (which were the file attribute setters for ext4 and xfs and have now been hoisted to the vfs) - Only allow the DAX flag to be set on files and directories" * tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: vfs: only allow FSSETXATTR to set DAX flag on files and dirs vfs: teach vfs_ioc_fssetxattr_check to check extent size hints vfs: teach vfs_ioc_fssetxattr_check to check project id info vfs: create a generic checking function for FS_IOC_FSSETXATTR vfs: create a generic checking and prep function for FS_IOC_SETFLAGS

vfs: create a generic checking and prep function for FS_IOC_SETFLAGS

2019-07-01T15:25:34+00:00

Create a generic function to check incoming FS_IOC_SETFLAGS flag values and later prepare the inode for updates so that we can standardize the implementations that follow ext4's flag values. Note that the efivarfs implementation no longer fails a no-op SETFLAGS without CAP_LINUX_IMMUTABLE since that's the behavior in ext*. Signed-off-by: Darrick J. Wong Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Acked-by: David Sterba Reviewed-by: Bob Peterson

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

efivarfs: Limit the rate for non-root to read files

2018-02-22T18:21:02+00:00

Each read from a file in efivarfs results in two calls to EFI (one to get the file size, another to get the actual data). On X86 these EFI calls result in broadcast system management interrupts (SMI) which affect performance of the whole system. A malicious user can loop performing reads from efivarfs bringing the system to its knees. Linus suggested per-user rate limit to solve this. So we add a ratelimit structure to "user_struct" and initialize it for the root user for no limit. When allocating user_struct for other users we set the limit to 100 per second. This could be used for other places that want to limit the rate of some detrimental user action. In efivarfs if the limit is exceeded when reading, we take an interruptible nap for 50ms and check the rate limit again. Signed-off-by: Tony Luck Acked-by: Ard Biesheuvel Signed-off-by: Linus Torvalds

efivarfs: Make efivarfs_file_ioctl() static

2016-05-07T05:06:13+00:00

There are no callers except through the file_operations struct below this, so it should be static like everything else here. Signed-off-by: Peter Jones Signed-off-by: Matt Fleming Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462570771-13324-6-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar

efi: Make efivarfs entries immutable by default

2016-02-10T16:25:52+00:00

"rm -rf" is bricking some peoples' laptops because of variables being used to store non-reinitializable firmware driver data that's required to POST the hardware. These are 100% bugs, and they need to be fixed, but in the mean time it shouldn't be easy to *accidentally* brick machines. We have to have delete working, and picking which variables do and don't work for deletion is quite intractable, so instead make everything immutable by default (except for a whitelist), and make tools that aren't quite so broad-spectrum unset the immutable flag. Signed-off-by: Peter Jones Tested-by: Lee, Chun-Yi Acked-by: Matthew Garrett Signed-off-by: Matt Fleming