linux/fs/proc
Linus Torvalds 66a97c2ec9 We still have some races in filesystem methods when exposed to RCU
pathwalk.  This series is a result of code audit (the second round
 of it) and it should deal with most of that stuff.  Exceptions: ntfs3
 ->d_hash()/->d_compare() and ceph_d_revalidate().  Up to maintainers (a
 note for NTFS folks - when documentation says that a method may not block,
 it *does* imply that blocking allocations are to be avoided.  Really).
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull RCU pathwalk fixes from Al Viro:
 "We still have some races in filesystem methods when exposed to RCU
  pathwalk. This series is a result of code audit (the second round of
  it) and it should deal with most of that stuff.

  Still pending: ntfs3 ->d_hash()/->d_compare() and ceph_d_revalidate().
  Up to maintainers (a note for NTFS folks - when documentation says
  that a method may not block, it *does* imply that blocking allocations
  are to be avoided. Really)"

[ More explanations for people who aren't familiar with the vagaries of
  RCU path walking: most of it is hidden from filesystems, but if a
  filesystem actively participates in the low-level path walking it
  needs to make sure the fields involved in that walk are RCU-safe.

  That "actively participate in low-level path walking" includes things
  like having its own ->d_hash()/->d_compare() routines, or by having
  its own directory permission function that doesn't just use the common
  helpers.  Having a ->d_revalidate() function will also have this issue.

  Note that instead of making everything RCU safe you can also choose to
  abort the RCU pathwalk if your operation cannot be done safely under
  RCU, but that obviously comes with a performance penalty. One common
  pattern is to allow the simple cases under RCU, and abort only if you
  need to do something more complicated.

  So not everything needs to be RCU-safe, and things like the inode etc
  that the VFS itself maintains obviously already are. But these fixes
  tend to be about properly RCU-delaying things like ->s_fs_info that
  are maintained by the filesystem and that got potentially released too
  early.   - Linus ]

* tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ext4_get_link(): fix breakage in RCU mode
  cifs_get_link(): bail out in unsafe case
  fuse: fix UAF in rcu pathwalks
  procfs: make freeing proc_fs_info rcu-delayed
  procfs: move dropping pde and pid from ->evict_inode() to ->free_inode()
  nfs: fix UAF on pathwalk running into umount
  nfs: make nfs_set_verifier() safe for use in RCU pathwalk
  afs: fix __afs_break_callback() / afs_drop_open_mmap() race
  hfsplus: switch to rcu-delayed unloading of nls and freeing ->s_fs_info
  exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper
  affs: free affs_sb_info with kfree_rcu()
  rcu pathwalk: prevent bogus hard errors from may_lookup()
  fs/super.c: don't drop ->s_user_ns until we free struct super_block itself
2024-02-25 09:29:05 -08:00
..
array.c fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats 2024-02-07 21:20:33 -08:00
base.c procfs: move dropping pde and pid from ->evict_inode() to ->free_inode() 2024-02-25 02:10:32 -05:00
bootconfig.c fs/proc: Add boot loader arguments as comment to /proc/bootconfig 2023-10-07 10:45:56 +09:00
cmdline.c proc: mark /proc/cmdline as permanent 2023-02-02 22:50:02 -08:00
consoles.c proc: consoles: use console_list_lock for list iteration 2022-12-02 11:25:02 +01:00
cpuinfo.c x86/aperfmperf: Replace aperfmperf_get_khz() 2022-04-27 20:22:19 +02:00
devices.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
fd.c file: convert to SLAB_TYPESAFE_BY_RCU 2023-10-19 11:02:48 +02:00
fd.h fs: port ->permission() to pass mnt_idmap 2023-01-19 09:24:28 +01:00
generic.c fs: pass the request_mask to generic_fillattr 2023-08-09 08:56:36 +02:00
inode.c procfs: move dropping pde and pid from ->evict_inode() to ->free_inode() 2024-02-25 02:10:32 -05:00
internal.h proc: Use lsmids instead of lsm names for attrs 2023-11-12 22:54:42 -05:00
interrupts.c
Kconfig proc: make config PROC_CHILDREN depend on PROC_FS 2022-10-03 14:21:43 -07:00
kcore.c proc/kcore: do not try to access unaccepted memory 2023-10-04 10:32:22 -07:00
kmsg.c printk changes for 6.1 2022-10-10 11:24:19 -07:00
loadavg.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
Makefile
meminfo.c mm: memtest: convert to memtest_report_meminfo() 2023-08-21 13:37:47 -07:00
namespaces.c Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-01-29 11:20:24 -08:00
nommu.c fs: create helper file_user_path() for user displayed mapped file path 2023-10-19 11:03:15 +02:00
page.c mm, pagemap: remove SLOB and SLQB from comments and documentation 2023-03-29 10:32:11 +02:00
proc_net.c v6.6-fs.proc.uapi 2023-08-28 11:43:19 -07:00
proc_sysctl.c misc cleanups (the part that hadn't been picked by individual fs trees) 2024-01-11 20:23:50 -08:00
proc_tty.c proc: delete unused <linux/uaccess.h> includes 2022-07-17 17:31:39 -07:00
root.c procfs: make freeing proc_fs_info rcu-delayed 2024-02-25 02:10:32 -05:00
self.c proc: convert to new timestamp accessors 2023-10-18 14:08:26 +02:00
softirqs.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
stat.c proc/stat: remove arch_idle_time() 2023-04-18 16:39:33 -07:00
task_mmu.c fs/proc/task_mmu: move mmu notification mechanism inside mm lock 2024-01-12 15:20:46 -08:00
task_nommu.c vfs-6.7.misc 2023-10-30 09:14:19 -10:00
thread_self.c proc: convert to new timestamp accessors 2023-10-18 14:08:26 +02:00
uptime.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
util.c
version.c proc: mark more files as permanent 2022-10-03 14:21:45 -07:00
vmcore.c proc/vmcore: fix signedness bug in read_from_oldmem() 2023-07-27 13:07:05 -07:00