linux/security
Michal Hocko 9897713fe1 bcachefs: do not use PF_MEMALLOC_NORECLAIM
Patch series "remove PF_MEMALLOC_NORECLAIM" v3.


This patch (of 2):

bch2_new_inode relies on PF_MEMALLOC_NORECLAIM to try to allocate a new
inode to achieve GFP_NOWAIT semantic while holding locks. If this
allocation fails it will drop locks and use GFP_NOFS allocation context.

We would like to drop PF_MEMALLOC_NORECLAIM because it is really
dangerous to use if the caller doesn't control the full call chain with
this flag set. E.g. if any of the function down the chain needed
GFP_NOFAIL request the PF_MEMALLOC_NORECLAIM would override this and
cause unexpected failure.

While this is not the case in this particular case using the scoped gfp
semantic is not really needed bacause we can easily pus the allocation
context down the chain without too much clutter.

[akpm@linux-foundation.org: fix kerneldoc warnings]
Link: https://lkml.kernel.org/r/20240926172940.167084-1-mhocko@kernel.org
Link: https://lkml.kernel.org/r/20240926172940.167084-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz> # For vfs changes
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: James Morris <jmorris@namei.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Serge E. Hallyn <serge@hallyn.com>
Cc: Yafang Shao <laoar.shao@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-10-09 12:47:18 -07:00
..
apparmor move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
bpf
integrity struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
ipe ipe: Add missing terminator to list of unit tests 2024-09-23 15:53:37 -04:00
keys move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
landlock Landlock updates for v6.12-rc1 2024-09-24 10:40:11 -07:00
loadpin
lockdown
safesetid
selinux bpf-next-6.12-struct-fd 2024-09-24 14:54:26 -07:00
smack lsm/stable-6.12 PR 20240923 2024-09-24 10:18:15 -07:00
tomoyo tomoyo: revert CONFIG_SECURITY_TOMOYO_LKM support 2024-10-04 11:41:22 -04:00
yama
commoncap.c
device_cgroup.c
inode.c
Kconfig
Kconfig.hardening hardening: Adjust dependencies in selection of MODVERSIONS 2024-09-28 13:56:03 -07:00
lsm_audit.c
lsm_syscalls.c
Makefile
min_addr.c
security.c bcachefs: do not use PF_MEMALLOC_NORECLAIM 2024-10-09 12:47:18 -07:00