view tests/test-audit-path.t @ 49000:dd6b67d5c256 stable

rust: fix unsound `OwningDirstateMap`

As per the previous patch, `OwningDirstateMap` is unsound. Self-referential
structs are difficult to implement correctly in Rust since the compiler is
free to move structs around as much as it wants to. They are also very rarely
needed in practice, so the state-of-the-art on how they should be done within
the Rust rules is still a bit new.

The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense)
of declaring self-referential structs. It is getting a lot attention and was
improved very quickly when soundness issues were found in the past: rather than
relying on our own (limited) review circle, we might as well use the de-facto
common crate to fix this problem. This will give us a much better chance of
finding issues should any new ones be discovered as well as the benefit of
fewer `unsafe` APIs of our own.

I was starting to think about how I would present a safe API to the old struct
but soon realized that the callback-based approach was already done in
`ouroboros`, along with a lot more care towards refusing incorrect structs.

In short: we don't return a mutable reference to the `DirstateMap` anymore, we
expect users of its API to pass a `FnOnce` that takes the map as an argument.
This allows our `OwningDirstateMap` to control the input and output lifetimes
of the code that modifies it to prevent such issues.

Changing to `ouroboros` meant changing every API with it, but it is relatively
low churn in the end. It correctly identified the example buggy modification of
`copy_map_insert` outlined in the previous patch as violating the borrow rules.

Differential Revision: https://phab.mercurial-scm.org/D12429

The simple store doesn't escape paths robustly and can't store paths
with periods, etc. So much of this test fails with it.
#require no-reposimplestore

  $ hg init

audit of .hg

  $ hg add .hg/00changelog.i
  abort: path contains illegal component: .hg/00changelog.i
  [10]

#if symlink

Symlinks

  $ mkdir a
  $ echo a > a/a
  $ hg ci -Ama
  adding a/a
  $ ln -s a b
  $ echo b > a/b
  $ hg add b/b
  abort: path 'b/b' traverses symbolic link 'b'
  [255]
  $ hg add b

should still fail - maybe

  $ hg add b/b
  abort: path 'b/b' traverses symbolic link 'b'
  [255]

  $ hg commit -m 'add symlink b'


Test symlink traversing when accessing history:
-----------------------------------------------

(build a changeset where the path exists as a directory)

  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ mkdir b
  $ echo c > b/a
  $ hg add b/a
  $ hg ci -m 'add directory b'
  created new head

Test that hg cat does not do anything wrong the working copy has 'b' as directory

  $ hg cat b/a
  c
  $ hg cat -r "desc(directory)" b/a
  c
  $ hg cat -r "desc(symlink)" b/a
  b/a: no such file in rev bc151a1f53bd
  [1]

Test that hg cat does not do anything wrong the working copy has 'b' as a symlink (issue4749)

  $ hg up 'desc(symlink)'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg cat b/a
  b/a: no such file in rev bc151a1f53bd
  [1]
  $ hg cat -r "desc(directory)" b/a
  c
  $ hg cat -r "desc(symlink)" b/a
  b/a: no such file in rev bc151a1f53bd
  [1]

#endif


unbundle tampered bundle

  $ hg init target
  $ cd target
  $ hg unbundle "$TESTDIR/bundles/tampered.hg"
  adding changesets
  adding manifests
  adding file changes
  added 5 changesets with 6 changes to 6 files (+4 heads)
  new changesets b7da9bf6b037:fc1393d727bc (5 drafts)
  (run 'hg heads' to see heads, 'hg merge' to merge)

attack .hg/test

  $ hg manifest -r0
  .hg/test
  $ hg update -Cr0
  abort: path contains illegal component: .hg/test
  [10]

attack foo/.hg/test

  $ hg manifest -r1
  foo/.hg/test
  $ hg update -Cr1
  abort: path 'foo/.hg/test' is inside nested repo 'foo'
  [10]

attack back/test where back symlinks to ..

  $ hg manifest -r2
  back
  back/test
#if symlink
  $ hg update -Cr2
  abort: path 'back/test' traverses symbolic link 'back'
  [255]
#else
('back' will be a file and cause some other system specific error)
  $ hg update -Cr2
  abort: $TESTTMP/target/back/test: $ENOTDIR$
  [255]
#endif

attack ../test

  $ hg manifest -r3
  ../test
  $ mkdir ../test
  $ echo data > ../test/file
  $ hg update -Cr3
  abort: path contains illegal component: ../test
  [10]
  $ cat ../test/file
  data

attack /tmp/test

  $ hg manifest -r4
  /tmp/test
  $ hg update -Cr4
  abort: path contains illegal component: /tmp/test
  [10]

  $ cd ..

Test symlink traversal on merge:
--------------------------------

#if symlink

set up symlink hell

  $ mkdir merge-symlink-out
  $ hg init merge-symlink
  $ cd merge-symlink
  $ touch base
  $ hg commit -qAm base
  $ ln -s ../merge-symlink-out a
  $ hg commit -qAm 'symlink a -> ../merge-symlink-out'
  $ hg up -q 0
  $ mkdir a
  $ touch a/poisoned
  $ hg commit -qAm 'file a/poisoned'
  $ hg log -G -T '{rev}: {desc}\n'
  @  2: file a/poisoned
  |
  | o  1: symlink a -> ../merge-symlink-out
  |/
  o  0: base
  

try trivial merge

  $ hg up -qC 1
  $ hg merge 2
  abort: path 'a/poisoned' traverses symbolic link 'a'
  [255]

try rebase onto other revision: cache of audited paths should be discarded,
and the rebase should fail (issue5628)

  $ hg up -qC 2
  $ hg rebase -s 2 -d 1 --config extensions.rebase=
  rebasing 2:e73c21d6b244 tip "file a/poisoned"
  abort: path 'a/poisoned' traverses symbolic link 'a'
  [255]
  $ ls ../merge-symlink-out

  $ cd ..

Test symlink traversal on update:
---------------------------------

  $ mkdir update-symlink-out
  $ hg init update-symlink
  $ cd update-symlink
  $ ln -s ../update-symlink-out a
  $ hg commit -qAm 'symlink a -> ../update-symlink-out'
  $ hg rm a
  $ mkdir a && touch a/b
  $ hg ci -qAm 'file a/b' a/b
  $ hg up -qC 0
  $ hg rm a
  $ mkdir a && touch a/c
  $ hg ci -qAm 'rm a, file a/c'
  $ hg log -G -T '{rev}: {desc}\n'
  @  2: rm a, file a/c
  |
  | o  1: file a/b
  |/
  o  0: symlink a -> ../update-symlink-out
  

try linear update where symlink already exists:

  $ hg up -qC 0
  $ hg up 1
  abort: path 'a/b' traverses symbolic link 'a'
  [255]

try linear update including symlinked directory and its content: paths are
audited first by calculateupdates(), where no symlink is created so both
'a' and 'a/b' are taken as good paths. still applyupdates() should fail.

  $ hg up -qC null
  $ hg up 1
  abort: path 'a/b' traverses symbolic link 'a'
  [255]
  $ ls ../update-symlink-out

try branch update replacing directory with symlink, and its content: the
path 'a' is audited as a directory first, which should be audited again as
a symlink.

  $ rm -f a
  $ hg up -qC 2
  $ hg up 1
  abort: path 'a/b' traverses symbolic link 'a'
  [255]
  $ ls ../update-symlink-out

  $ cd ..

#endif