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mirror of https://gitlab.com/apparmor/apparmor synced 2025-08-22 01:57:43 +00:00

278 Commits

Author SHA1 Message Date
Georgia Garcia
43fa5f88a7 parser: fix cases leaks when new state creation fails
For every item in "cases", a new state is created, but if the creation
of one of them fails, the rest of the items in that list would not be
deleted and would leak. Fix it by continuing to iterate over the items
in the list and delete them, and then re-throw the exception.

$ /usr/bin/valgrind --leak-check=full --error-exitcode=151 ../apparmor_parser -Q -I simple_tests/ -M ./features_files/features.all simple_tests/xtrans/x-conflict.sd

==564911== 208 (48 direct, 160 indirect) bytes in 1 blocks are definitely lost in loss record 15 of 19
==564911==    at 0x4846FA3: operator new(unsigned long) (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==564911==    by 0x179E74: CharNode::follow(Cases&) (expr-tree.h:447)
==564911==    by 0x189F8B: DFA::update_state_transitions(optflags const&, State*) (hfa.cc:376)
==564911==    by 0x18A25B: DFA::process_work_queue(char const*, optflags const&) (hfa.cc:442)
==564911==    by 0x18CB65: DFA::DFA(Node*, optflags const&, bool) (hfa.cc:486)
==564911==    by 0x178263: aare_rules::create_chfa(int*, std::vector<aa_perms, std::allocator<aa_perms> >&, optflags const&, bool, bool) (aare_rules.cc:258)
==564911==    by 0x178A4F: aare_rules::create_dfablob(unsigned long*, int*, std::vector<aa_perms, std::allocator<aa_perms> >&, optflags const&, bool, bool) (aare_rules.cc:359)
==564911==    by 0x14E4E1: process_profile_regex(Profile*) (parser_regex.c:791)
==564911==    by 0x154CDF: process_profile_rules(Profile*) (parser_policy.c:194)
==564911==    by 0x154E0F: post_process_profile(Profile*, int) (parser_policy.c:240)
==564911==    by 0x154F7A: post_process_policy_list (parser_policy.c:257)
==564911==    by 0x154F7A: post_process_policy(int) (parser_policy.c:267)
==564911==    by 0x141B17: process_profile(int, aa_kernel_interface*, char const*, aa_policy_cache*) (parser_main.c:1227)

Fixes: https://gitlab.com/apparmor/apparmor/-/issues/534
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
2025-08-06 19:15:37 -03:00
Georgia Garcia
bb03d9ee08 parser: fix leak on conflicting x modifiers
When the "conflicting x modifiers" exception was thrown, the DFA
object creation would fail, therefore the destructor would not be
called and the states previously allocated would leak.

Unfortunately there's no way to call the destructor if the object was
not created, so I moved the contents of the destructor into a cleanup
helper function to be called in both instances.

$ /usr/bin/valgrind --leak-check=full --error-exitcode=151 ../apparmor_parser -Q -I simple_tests/ -M ./features_files/features.all simple_tests/xtrans/x-conflict.sd

==564911== 592 (112 direct, 480 indirect) bytes in 1 blocks are definitely lost in loss record 16 of 19
==564911==    at 0x4846FA3: operator new(unsigned long) (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==564911==    by 0x189C9A: DFA::add_new_state(optflags const&, std::set<ImportantNode*, std::less<ImportantNode*>, std::allocator<ImportantNode*> >*, std::set<ImportantNode*, std::less<ImportantNode*>, std::allocator<ImportantNode*> >*, State*) (hfa.cc:337)
==564911==    by 0x18CB22: add_new_state (hfa.cc:357)
==564911==    by 0x18CB22: DFA::DFA(Node*, optflags const&, bool) (hfa.cc:473)
==564911==    by 0x178263: aare_rules::create_chfa(int*, std::vector<aa_perms, std::allocator<aa_perms> >&, optflags const&, bool, bool) (aare_rules.cc:258)
==564911==    by 0x178A4F: aare_rules::create_dfablob(unsigned long*, int*, std::vector<aa_perms, std::allocator<aa_perms> >&, optflags const&, bool, bool) (aare_rules.cc:359)
==564911==    by 0x14E4E1: process_profile_regex(Profile*) (parser_regex.c:791)
==564911==    by 0x154CDF: process_profile_rules(Profile*) (parser_policy.c:194)
==564911==    by 0x154E0F: post_process_profile(Profile*, int) (parser_policy.c:240)
==564911==    by 0x154F7A: post_process_policy_list (parser_policy.c:257)
==564911==    by 0x154F7A: post_process_policy(int) (parser_policy.c:267)
==564911==    by 0x141B17: process_profile(int, aa_kernel_interface*, char const*, aa_policy_cache*) (parser_main.c:1227)
==564911==    by 0x135421: main (parser_main.c:1771)

Fixes: https://gitlab.com/apparmor/apparmor/-/issues/534
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
2025-08-06 19:15:37 -03:00
Christian Boltz
45a7cc1ed0
Fix whitespace in hfa.h
This got broken in 0f36070a54764deb6e5186443d81ba05ea17216a / https://gitlab.com/apparmor/apparmor/-/merge_requests/1750
2025-07-31 21:28:03 +02:00
John Johansen
514bf114b2 parser: drop unused map_xbits()
The map_xbits() is currently unused so drop it.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-31 10:23:22 -07:00
John Johansen
0430080a16 parser: drop unused create_welded_dfablob and related code
Their is no reason for the parse to stitch 2 dfas together this way.
In the future there will be better ways to do this using unconpressed
dfas.

Dropping this also allows for some simplification, in other parts of
the code.

Drop the dead/unused code

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-31 10:23:22 -07:00
John Johansen
0f36070a54 parser: drop support for prompt_compat_permsv1, and prompt_compat_dev
prompt_compat_permsv1 and prompt_compat_dev were used to support
prompt during early dev. We do not support any kernel using these
so drop them.

This also allows us to drop the propogation of prompt as a parameter
through several functions.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-07-31 10:23:22 -07:00
John Johansen
330d202586 Merge branch 'master' into 'override'
# Conflicts:
#   parser/libapparmor_re/expr-tree.h
2025-05-07 23:04:59 +00:00
John Johansen
ec2549be2a Merge refactor(bison): replace deprecated name-prefix with %define api.prefix
%name-prefix is deprecated in Bison 2.6.  
<https://savannah.gnu.org/news/?id=7269>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1668
Approved-by: Ryan Lee <rlee287@yahoo.com>
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2025-05-07 22:54:06 +00:00
John Johansen
b50ec6ca36 Merge fix: avoid using namespace std; in header files
using directive in a header file is a bad practice because it may lead
to unexpected results.

https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rs-using-directive

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1664
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2025-05-07 22:53:26 +00:00
John Johansen
06e349345e parser: fix failure to properly apply deny clearing in perms accumulation
The internal permission accumulation is currently broken in that
the ordering of rules matter to whether deny is clearing accumulated
perms.

If a deny node comes before an allow node the deny bits will get set
but the following allow bits won't get cleared by the deny node.

This isn't currently an actual issue for mediation as the deny
bit will be applied at one of
  1. apply_and_clear_deny
  2. permission remapping
  3. run time mediation

but it does result in the internal state having sometimes having both
allow and deny bits set, dependent on order of computation, resulting
in state machines with different sizes because minimization
partitioning is based on the internal permissions.

This means that dfa minimization may not result in a truly minimal
state machine, and even worse can cause inconsistenty and failure in
tests that rely on internal state like the equality and minimization
test, as seen in https://gitlab.com/apparmor/apparmor/-/issues/513

The failure was due to musl stl sets implementation producing a
different ordering of the nodes than glibc. So when the permissions
where accumulated the internal set of permissions were different.

Fix this by giving the different node classes their own internal priority.
This will ensure the bits are properly cleared for that priority before
accumulating.

Note: other ways of fixing.

1. Fixup internal accumulation to use accumulating perms of "higher"
   priority as part of the mask (deny and allow mask prompt).
2. Do a hard masking apply at the end after all bits have been accumulated
   (ie, in accept_perms after the for loop).

the priority route was chosen because it is a little smaller and
scales better if we get new Node types we have to deal with
(eg. planned complain node).

BugLink: https://gitlab.com/apparmor/apparmor/-/issues/513
Fixes: 1ebd99115 ("parser: change priority so that it accumulates based on permissions")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-05-07 01:41:59 -07:00
Eisuke Kawashima
5526138483
fix(inconsistent-missing-override): add missed override specifiers 2025-05-05 17:52:52 +09:00
Eisuke Kawashima
18c0d003ef
fix(non-virtual-dtor): add missed virtual destructor 2025-05-05 17:52:48 +09:00
Eisuke Kawashima
9c6ae3cf5c
refactor(bison): replace deprecated name-prefix with %define api.prefix
%name-prefix is deprecated in Bison 2.6.
https://savannah.gnu.org/news/?id=7269
2025-05-05 17:47:29 +09:00
Eisuke Kawashima
7d5a021023
fix: avoid using namespace std; in header files
using directive in a header file is a bad practice because it may lead
to unexpected results.

https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rs-using-directive
2025-05-04 23:14:36 +09:00
John Johansen
fcd814bc51 parser: Dump more partition debug information
We need to be able to dump the initial partition assignments, and then
the partitions after minimization but before remapping to be able to
check on what is being done by minimization.

Add these as part of -D dfa-minimize-partitions

Ideally we would rework the code so that the existing mininimization
dump could share the dump routine but, its interwined with computation
state and information is thrown away before reaching the end.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-04-30 01:19:13 -07:00
Ryan Lee
4286423fe2 parser: hfa.cc debug promt->prompt typofix
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
2025-02-18 11:53:35 -08:00
John Johansen
1ebd991155 parser: change priority so that it accumulates based on permissions
The current behavior of priority rules can be non-intuitive with
higher priority rules completely overriding lower priority rules even in
permissions not held in common. This behavior does have use cases but
its can be very confusing, and does not normal policy behavior

Eg.
  priority=0 allow r /**,
  priority=1 deny  w /**,

will result in no allowed permissions even though the deny rule is
only removing the w permission, beause the higher priority rule
completely over ride lower priority permissions sets (including
none shared permissions).

Instead move to tracking the priority at a per permission level. This
allows the w permission to still override at priority 1, while the
read permission is allowed at priority 0.

The final constructed state will still drop priority for the final
permission set on the state.

Note: this patch updates the equality tests for the cases where
the complete override behavior was being tested for.

The complete override behavior will be reintroduced in a future
patch with a keyword extension, enabling that behavior to be used
for ordered blocks etc.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-02-06 11:02:20 -08:00
John Johansen
cc31a0da22 parser: drop priority from state permissions
The priority field is only used during state construction, and can
even prevent later optimizations like minimization. The parser already
explcitily clears the states priority field as part of the last thing
done during construction so it doesn't prevent minimization
optimizations.

This means the state priority not only wastes storage because it is
unused post construction but if used it could introduce regressions,
or other issues.

The change to the minimization tests just removes looking for the
priority field that is no longer reported.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-02-06 10:53:19 -08:00
John Johansen
9221d291ec parser: stop using dynamic_cast for prompt permission calculations
Like was done for the other MatchFlags switch to using a node type
instead of dynamic_cast as this will result in a performance
improvement.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-02-06 08:34:02 -08:00
John Johansen
2e42c33f48 Merge parser: add backend pipeline ordering info to README
Add a basic overview of the ordering of the backend of the compiler
and which stages specific dump info lines up with.

Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1470
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2025-01-16 19:32:26 +00:00
John Johansen
c57d727482 parser: add backend pipeline ordering info to README
Add a basic overview of the ordering of the backend of the compiler
and which stages specific dump info lines up with.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-01-10 23:35:57 -08:00
John Johansen
72f9952a5f Merge parser: add a hfa dump that matches the renumbered chfa
Construction of the chfa can reorder states from what the numbering
given during the hfa constuctions because of reordering for better
compression, dead state removal to ensure better packing etc.

This however means the dfa dump is difficult (it is possible using
multiple dumpes) to match up to the chfa that the kernel is
using. Make this easier by making the dfa dump be able to take
the remapping as input, and provide an option to dump the
chfa equivalent hfa.

Renumbered states will show up as {new <== {orig}} in the dump

Eg.
```
--D dfa-states
{1} <== priority (allow/deny/prompt/audit/quiet)
{5} 0 (0x 4/0//0/0/0)

{1} perms: none
    0x2 -> {5}  0 (0x 4/0//0/0/0)
    0x4 -> {5}  0 (0x 4/0//0/0/0)
    \a 0x7 -> {5}  0 (0x 4/0//0/0/0)
    \t 0x9 -> {5}  0 (0x 4/0//0/0/0)
    \n 0xa -> {5}  0 (0x 4/0//0/0/0)
    \  0x20 -> {5}  0 (0x 4/0//0/0/0)
    4 0x34 -> {3}
{3} perms: none
    0x0 -> {6}
{6} perms: none
    1 0x31 -> {5}  0 (0x 4/0//0/0/0)
```

```
-D dfa-compressed-states
{1} <== priority (allow/deny/prompt/audit/quiet)
{2 == {5}} 0 (0x 4/0//0/0/0)

{1} perms: none
    0x2 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    0x4 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \a 0x7 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \t 0x9 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \n 0xa -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \  0x20 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    4 0x34 -> {3}
{3} perms: none
    0x0 -> {4 == {6}}
{4 == {6}} perms: none
    1 0x31 -> {2 == {5}}  0 (0x 4/0//0/0/0)
```

Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1474
Approved-by: Georgia Garcia <georgia.garcia@canonical.com>
Merged-by: John Johansen <john@jjmx.net>
2025-01-09 19:04:13 +00:00
John Johansen
50452e1147 parser: add a hfa dump that matches the renumbered chfa
Construction of the chfa can reorder states from what the numbering
given during the hfa constuctions because of reordering for better
compression, dead state removal to ensure better packing etc.

This however means the dfa dump is difficult (it is possible using
multiple dumpes) to match up to the chfa that the kernel is
using. Make this easier by making the dfa dump be able to take the
emapping as input, and provide an option to dump the chfa equivalent
hfa.

Renumbered states will show up as {new <== {orig}} in the dump

Eg.
--D dfa-states
{1} <== priority (allow/deny/prompt/audit/quiet)
{5} 0 (0x 4/0//0/0/0)

{1} perms: none
    0x2 -> {5}  0 (0x 4/0//0/0/0)
    0x4 -> {5}  0 (0x 4/0//0/0/0)
    \a 0x7 -> {5}  0 (0x 4/0//0/0/0)
    \t 0x9 -> {5}  0 (0x 4/0//0/0/0)
    \n 0xa -> {5}  0 (0x 4/0//0/0/0)
    \  0x20 -> {5}  0 (0x 4/0//0/0/0)
    4 0x34 -> {3}
{3} perms: none
    0x0 -> {6}
{6} perms: none
    1 0x31 -> {5}  0 (0x 4/0//0/0/0)

-D dfa-compressed-states
{1} <== priority (allow/deny/prompt/audit/quiet)
{2 == {5}} 0 (0x 4/0//0/0/0)

{1} perms: none
    0x2 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    0x4 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \a 0x7 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \t 0x9 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \n 0xa -> {2 == {5}}  0 (0x 4/0//0/0/0)
    \  0x20 -> {2 == {5}}  0 (0x 4/0//0/0/0)
    4 0x34 -> {3}
{3} perms: none
    0x0 -> {4 == {6}}
{4 == {6}} perms: none
    1 0x31 -> {2 == {5}}  0 (0x 4/0//0/0/0)

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-01-03 14:18:50 -08:00
John Johansen
4fb3dbc7b3 parser: improve unreachable state removal
Currently states are added to the reachable set when they are popped
from the workqueue. This however can result in states being
added to the work queue multiple times and reprocessed.

Eg. If state 2 has the transitions, and 9 is not in the reachable set
  a -> 9
  b -> 9
  c -> 9
  d -> 9
  e -> 3

then 9 will get pushed onto the work 4 times. Even worse other states
on the workqueue may also add state 9 to the workqueue because it has
not been added to the reachable set.

Instead add states to the reachable set when they are added to the
workqueue. The first encounter with a state will result in it being
reachable and all other encounters will see that it already in the set
and not add it to the workqueue.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2025-01-01 17:16:17 -08:00
John Johansen
5d2a38e816 parser: add some new dfa dump options.
The dfa goes through several stages during the build. Allow dumping it
at the various stages instead of only at the end.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-12-22 15:02:04 -08:00
John Johansen
2e77129e15 Merge parser: fix expr MatchFlag dump
Match Flags convert output to hex but don't restore after outputting
the flag resulting in following numbers being hex encoded. This
results in dumps that can be confusing eg.

rule: \d2  ->  \x2 priority=1001 (0x4/0)< 0x4>

rule: \d7  ->  \a priority=3e9 (0x4/0)< 0x4>

rule: \d10  ->  \n priority=3e9 (0x4/0)< 0x4>

rule: \d9  ->  \t priority=3e9 (0x4/0)< 0x4>

rule: \d14  ->  \xe priority=1001 (0x4/0)< 0x4>

where priority=3e9 is the hex encoded priority 1001.

Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1419
Approved-by: Maxime Bélair <maxime.belair@canonical.com>
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2024-11-15 17:41:13 +00:00
John Johansen
015b41aeb4 Merge parser: improve libapparmor_re build and dump info
Fix libapparmor_re/Makefile so it works correctly with rebuilds and improve state machine dump information, to aid with debugging of permission handling during the compile.

Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1410
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2024-11-15 00:32:30 +00:00
Ryan Lee
88719dbb7b Fix infinite loop in chfa.cc:weld_file_to_policy
This is simple enough to fix even if weld_file_to_policy isn't used in practice
with the compat layer that uses it being a target for deletion

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
2024-11-13 15:46:38 -08:00
John Johansen
a31343c5f7 parser: fix expr MatchFlag dump
Match Flags convert output to hex but don't restore after outputting
the flag resulting in following numbers being hex encoded. This
results in dumps that can be confusing eg.

rule: \d2  ->  \x2 priority=1001 (0x4/0)< 0x4>

rule: \d7  ->  \a priority=3e9 (0x4/0)< 0x4>

rule: \d10  ->  \n priority=3e9 (0x4/0)< 0x4>

rule: \d9  ->  \t priority=3e9 (0x4/0)< 0x4>

rule: \d14  ->  \xe priority=1001 (0x4/0)< 0x4>

where priority=3e9 is the hex encoded priority 1001.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-11 14:39:40 -08:00
John Johansen
f24fc4841f Merge parser: fix mapping of AA_CONT_MATCH for policydb compat entries
The mapping of AA_CONT_MATCH was being dropped resulting in the
tcp tests failing because they would only match up to the first conditional
match check in the layout.

Bug: https://gitlab.com/apparmor/apparmor/-/issues/462
Fixes: e29f5ce5f ("parser: if extended perms are supported by the kernel build a permstable")
Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1409
Approved-by: Ryan Lee <rlee287@yahoo.com>
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2024-11-11 20:53:08 +00:00
John Johansen
eb365b374d Merge parser: bug fix do not change auditing information when applying deny
The parser recently changed how/where deny information is applied.
commit 1fa45b7c1 ("parser: dfa minimization prepare for extended
permissions") removed the implicit filtering of explicit denies during
the minimization pass. The implicit clear allowed the explicit
information to be carried into the minimization pass and merged with
implicit denies. The end result being a minimized dfa with the explicit
deny information available to be applied post minimization, and
then dropped later at permission encoding in the accept entries.

Extended permission however enable carrying explicit deny information
into the kernel to fix certain bugs like complain mode not being
able to distinguish between implicit and explicit deny rules (ie.
deny rules get ignored in complain mode). However keeping explicit
deny information when unnecessary result in a larger state machine
than necessary and slower compiles.

commit 179c1c1ba ("parser: fix minimization check for filtering_deny")
Moved the explicit apply_and_clear_deny() pass to before minimization
to restore mnimization's ability to create a minimized dfa with
explicit and implicit deny information merged but this also cleared
the explicit deny information that used to be carried through
minimization. This meant that when the deny information was applied
post minimization it resulted in the audit and quiet information
being cleared.

This resulted in the query_label tests failing as they are checking
for the expected audit infomation in the permissions.

Fixes: 179c1c1ba ("parser: fix minimization check for filtering_deny")
Bug: https://gitlab.com/apparmor/apparmor/-/issues/461
Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1408
Approved-by: Ryan Lee <rlee287@yahoo.com>
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
2024-11-11 20:52:19 +00:00
Ryan Lee
d1cecd5f46 Don't use hardcoded cerr in hfa.h State::dump
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
2024-11-06 18:00:16 -08:00
John Johansen
15a02e0948 parser: fix mapping of AA_CONT_MATCH for policydb compat entries
The mapping of AA_CONT_MATCH was being dropped resulting in the
tcp tests failing because they would only match up to the first conditional
match check in the layout.

Bug: https://gitlab.com/apparmor/apparmor/-/issues/462
Fixes: e29f5ce5f ("parser: if extended perms are supported by the kernel build a permstable")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-06 12:33:36 -08:00
John Johansen
45964d34e7 parser: add the abilitiy to dump the permissions table
Instead of encoding permissions in the accept and accept2 tables
extended perms uses a permissions table and accept becomes an index
into the table.

Add the ability to dump the permissions table so that it can be
compared and debugged.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-06 11:44:30 -08:00
John Johansen
00dedf10ad parser: add the accept2 table entry to the chfa dump
The chfa dump is missing information about the accept2 entry. The
accept2 information is necessary to help with debugging state machine
builds as accept2 is used to store quiet and audit information in the
old format or conditional information in the extended perms format.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-06 09:21:03 -08:00
John Johansen
7cc7f47424 parser: fix and cleanup libapparmor_re/Makefile
The Makefile is missing some of its .h depenedncies causing compiles
to either fail or worse result in bad builds when rebuilding in an
already built tree.

Move the header dependencies into a variable and use it for each
target. While some targets don't need every include as a dependency
and this will result in unnecessary rebuilds in some cases, it makes
the Makefile cleaner, easier to maintain and makes sure a dependency
isn't accidentally missed.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-06 09:20:51 -08:00
John Johansen
9ea0d4f89b parser: bug fix do not change auditing information when applying deny
The parser recently changed how/where deny information is applied.
commit 1fa45b7c1 ("parser: dfa minimization prepare for extended
permissions") removed the implicit filtering of explicit denies during
the minimization pass. The implicit clear allowed the explicit
information to be carried into the minimization pass and merged with
implicit denies. The end result being a minimized dfa with the explicit
deny information available to be applied post minimization, and
then dropped later at permission encoding in the accept entries.

Extended permission however enable carrying explicit deny information
into the kernel to fix certain bugs like complain mode not being
able to distinguish between implicit and explicit deny rules (ie.
deny rules get ignored in complain mode). However keeping explicit
deny information when unnecessary result in a larger state machine
than necessary and slower compiles.

commit 179c1c1ba ("parser: fix minimization check for filtering_deny")
Moved the explicit apply_and_clear_deny() pass to before minimization
to restore mnimization's ability to create a minimized dfa with
explicit and implicit deny information merged but this also cleared
the explicit deny information that used to be carried through
minimization. This meant that when the deny information was applied
post minimization it resulted in the audit and quiet information
being cleared.

This resulted in the query_label tests failing as they are checking
for the expected audit infomation in the permissions.

Fixes: 179c1c1ba ("parser: fix minimization check for filtering_deny")
Bug: https://gitlab.com/apparmor/apparmor/-/issues/461
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-06 09:11:43 -08:00
John Johansen
99261bad11 Merge Fix memory leak in aare_rules UniquePermsCache
When the find fails but the insertion also fails, we leak the new node
that we generated. Delete the new node in this case to avoid leaking
memory.

The question remains, however, as to whether we should implement `operator==` in addition to `operator<` so that they are consistent with each other and `find` works correctly.

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1399
Approved-by: Georgia Garcia <georgia.garcia@canonical.com>
Merged-by: John Johansen <john@jjmx.net>
2024-10-29 11:12:05 +00:00
Ryan Lee
81950dae4e Fix memory leak in aare_rules UniquePermsCache
When the find fails but the insertion also fails, we leak the new node
that we generated. Delete the new node in this case to avoid leaking
memory.

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
2024-10-28 12:23:17 +01:00
John Johansen
e9d6e0ba14 Merge parser: fix minimization check for filtering deny
commit 1fa45b7c1 ("parser: dfa minimization prepare for extended
permissions") removed implicit filtering of explicit denies in the
minimization pass (the information was ignored in building the set of
final accept states).

The filtering of explicit denies reduces the size of the produced
dfa. Since we need to be smarter about when explicit denies are
kept (eg. during complain mode), and most dfas are limited to 65k
states we currently need to filter explicit deny perms by default.

To compensate commit 2737cb2c2 ("parser: minimization - remove
unnecessary second minimization pass") moved the
apply_and_clear_deny() to before minimization. However its check to
apply removal denials before minimization is broken. Remove minimization
triggering apply_and_clear_deny() and just set the FILTER_DENY flag
by default, until we have better selection of rules/conditions where
explicit deny information should be carried through to the backend.

Fixes: 2737cb2c2 ("parser: minimization - remove unnecessary second minimization pass")
Signed-off-by: John Johansen <john.johansen@canonical.com>

MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1397
Approved-by: Georgia Garcia <georgia.garcia@canonical.com>
Merged-by: John Johansen <john@jjmx.net>
2024-10-28 11:22:57 +00:00
John Johansen
e2d55844a2 parser: fix integer overflow bug in rule priority comparisons
There is an integer overflow when comparing priorities when cmp is
used because it uses subtraction to find lessthan, equal, and greater
than in one operation.

But INT_MAX and INT_MIN are being used by priorities and this results
in INT_MAX - INT_MIN and INT_MIN - INT_MAX which are both overflows
causing an incorrect comparison result and selection of the wrong
rule permission.

Closes: https://gitlab.com/apparmor/apparmor/-/issues/452
Fixes: e3fca60d1 ("parser: add the ability to specify a priority prefix to rules")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-10-28 04:03:53 -07:00
John Johansen
179c1c1ba7 parser: fix minimization check for filtering_deny
commit 1fa45b7c1 ("parser: dfa minimization prepare for extended
permissions") removed implicit filtering of explicit denies in the
minimization pass (the information was ignored in building the set of
final accept states).

The filtering of explicit denies reduces the size of the produced
dfa. Since we need to be smarter about when explicit denies are
kept (eg. during complain mode), and most dfas are limited to 65k
states we currently need to filter explicit deny perms by default.

To compensate commit 2737cb2c2 ("parser: minimization - remove
unnecessary second minimization pass") moved the
apply_and_clear_deny() to before minimization. However its check to
apply removal denials before minimization is broken. Remove minimization
triggering apply_and_clear_deny() and just set the FILTER_DENY flag
by default, until we have better selection of rules/conditions where
explicit deny information should be carried through to the backend.

Fixes: 2737cb2c2 ("parser: minimization - remove unnecessary second minimization pass")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-10-25 01:14:18 -07:00
John Johansen
2737cb2c2b parser: minimization - remove unnecessary second minimization pass
Moving apply_and_clear_deny() before the first minimization pass, which
was necessary to propperly support building accept information for
older none extended permission dfas, allows us to also get rid of doing a
second minimization pass if we want to force clearing explicit deny
info from extended permission tables.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 17:15:24 -07:00
John Johansen
1fa45b7c1f parser: dfa minimization prepare for extended permissions
Instead of compressing the permission set into 128 bit and using that
as the index in the permission map, just use the permissions directly
as the index into the permission map.

Note: this will break equality and minimization tests. Because deny
is not being cleared it will result in more partitions in the initial
setup. This will be addressed and the tests will be fixed in a follow
on patch.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 17:15:24 -07:00
John Johansen
5ff00bba3a parser: drop unused hash minimization remnants
Hash minimization was removed in
  f0b154528 Fix dfa minimization

however some remnants of minimization remained. A comment and the use
of the hash but only as a 0 value. Drop this dead code and comment.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 17:15:24 -07:00
John Johansen
012dcb6489 parser: only use 32 bit next/check tables if required
If the state machine does not requires more than 2^16 states use the
dfa16 encoding for next/check tables to keep the dfa size small.

Bug: https://gitlab.com/apparmor/apparmor/-/issues/419
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 17:01:32 -07:00
John Johansen
f86fda02f5 parser: fix 16 bit state limitation
The hfa stores next/check transitions in 16 bit fields to reduce memory
usage. However this means the state machine can on contain 2^16
states.

Allow the next/check tables to be 32 bit. This theoretically could allow
for 2^32 states however the base table uses the top 8 bits as flags
giving us only 2^24 bits to index into the next/check tables. With
most states having at least 1 transition this effectively caps the
number of states at 2^24.

To obtain 2^32 possible states a flags table needs to be added. Add
a skeleton around supporting a flags table, so we can note the remaining
work that needs to be done. This patch will only allow for 2^24 states.

Bug: https://gitlab.com/apparmor/apparmor/-/issues/419

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 17:01:30 -07:00
John Johansen
b72cae79cb parser: support uin128_t key as a pair of uint64_t numbers
__uint128 is not supported by gcc on 32 bit architectures so rework
the 128 bit map key to be a pair of 64bit numbers.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 15:47:13 -07:00
John Johansen
373c095b3e parser: switch backend to perm32_t for permission bits
switch permission bits to use perm32_t type. This is just annotating
the code as it is no different than uint32_t at this time.

We do not convert the accept values as they may be mapped permission
bits or they may be and index value.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 15:47:13 -07:00
John Johansen
89673d0c5e parser: don't set xbits when using permstable32_v1
The use of xbits can not pass verification so we need to leave them
off this makes the profile a leaf profile.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-08-14 15:47:13 -07:00