Allowing access to a debug flag can greatly improve policy debugging.
This is different than the debug mode of old, that was removed. It only
will trigger additional messages to the kernel ring buffer, not
the audit log, and it does not change mediation.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The check isn't correct, it should be checking for capability
MAC_ADMIN, but in the future that won't be correct either. Instead
rely on the kernel to check permission to load policy, which it alread
does as it is possible to by-pass the parser to load policy.
Also improve the error message when the kernel does deny
loading policy due to failed permission checks.
Signed-off-by: John Johansen <john.johansen@canonical.com>
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1044
Approved-by: Seth Arnold <seth.arnold@gmail.com>
Merged-by: John Johansen <john@jjmx.net>
The check isn't correct, it should be checking for capability
MAC_ADMIN, but in the future that won't be correct either. Instead
rely on the kernel to check permission to load policy, which it alread
does as it is possible to by-pass the parser to load policy.
Also improve the error message when the kernel does deny
loading policy due to failed permission checks.
Signed-off-by: John Johansen <john.johansen@canonical.com>
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1048
made it so rules like
mount slave /snap/bin/** -> /**,
mount /snap/bin/** -> /**,
would get passed into change_mount_type rule generation when they
shouldn't have been. This would result in two different errors.
1. If kernel mount flags were present on the rule. The error would
be caught causing an error to be returned, causing profile compilation
to fail.
2. If the rule did not contain explicit flags then rule would generate
change_mount_type permissions based on souly the mount point. And
the implied set of flags. However this is incorrect as it should
not generate change_mount permissions for this type of rule. Not
only does it ignore the source/device type condition but it
generates permissions that were never intended.
When used in combination with a deny prefix this overly broad
rule can result in almost all mount rules being denied, as the
denial takes priority over the allow mount rules.
Fixes: https://bugs.launchpad.net/apparmor/+bug/2023814
Fixes: https://bugzilla.opensuse.org/show_bug.cgi?id=1211989
Fixes: 9d3f8c6cc ("parser: fix parsing of source as mount point for propagation type flags")
Fixes: MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1048
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1054
Signed-off-by: John Johansen <john.johansen@canonical.com>
(cherry picked from commit 86d193e183)
Signed-off-by: John Johansen <john.johansen@canonical.com>
Before 300889c3a, mount rules would compile policy when using source
as mount point for rules that contain propagation type flags, such as
unbindable, runbindable, private, rprivate, slave, rslave, shared, and
rshared. Even though it compiled, the rule generated would not work as
expected.
This commit fixes both issues. It allows the usage of source as mount
point for the specified flags, albeit with a deprecation warning, and
it correctly generates the mount rule.
The policy fails to load when both source and mount point are
specified, keeping the original behavior (reference
parser/tst/simple_tests/mount/bad_opt_10.sd for example).
Fixes: https://bugs.launchpad.net/bugs/1648245
Fixes: https://bugs.launchpad.net/bugs/2023025
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
If `else if (preprocess_only)` is true, the more strict condition
`else if (!include_file && preprocess_only)` won't be reached if it gets
checked after the shorter condition.
Exchange the two sections so that both code paths can be reached.
Fixes coverity CID 312499: Control flow issues (DEADCODE)
This was probably introduced in 7dcf013bca / https://gitlab.com/apparmor/apparmor/-/merge_requests/743 which means we'll need to backport this fix to 3.0 and 3.1.
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/1039
Approved-by: Georgia Garcia <georgia.garcia@canonical.com>
Merged-by: John Johansen <john@jjmx.net>
If `else if (preprocess_only)` is true, the more strict condition
`else if (!include_file && preprocess_only)` won't be reached if it gets
checked after the shorter condition.
Exchange the two sections so that both code paths can be reached.
Fixes coverity CID 312499: Control flow issues (DEADCODE)
The conflicting flags value message was hard to read
conflicting flag value = lazytimenolazytime
change it to
conflicting flag values = lazytime, nolazytime
Signed-off-by: John Johansen <john.johansen@canonical.com>
Adds the corresponding `MS_NOSYMFOLLOW` flag to parser/mount.h as well,
defined as (1 << 8) just as in the util-linux and the kernel.
Signed-off-by: Oliver Calder <oliver.calder@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
This patch adds the following mount options: 'nostrictatime',
'lazytime', and 'nolazytime'.
The MS_STRICTATIME mount flag already existed, and 'nostrictatime' was
listed along with 'strictatime' in the comments of parser/mount.cc, so
this patch adds a mapping for 'nostrictatime' to clear MS_STRICTATIME.
Additionally, the Linux kernel includes the 'lazytime' option with
MS_LAZYTIME mapping to (1<<25), so this patch adds MS_LAZYTIME to
parser/mount.h and the corresponding mappings in parser/mount.cc for
'lazytime' and 'nolazytime'.
Signed-off-by: Oliver Calder <oliver.calder@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The chfa equivalence class shouldn't be a reference. Its needs to
actually exist and be part of the class during later method calls.
As a reference it leads to bad references when used later.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The code for add_local_entry is actually currently unused and will
have to change anyways by the time it is. Some drop it and the
associated variables.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Another step towards having a block rule and retaining parsed rule
structure. Setup the parse to use a common block pattern, that when
we are ready will become an actual rule.
Signed-off-by: John Johansen <john.johansen@canonical.com>
In preparation for file rules and rule duplication removal add
flags to rule_t with the first flag indicating if the rule is
deleted.
We do this instead of actually deleting the rule so we can hold
on to the rule for debug and printing output in the future.
Signed-off-by: John Johansen <john.johansen@canonical.com>
in preparation for file rules switching to rule_t add a method to
indicate whether a particular rule is mergeable/dedupable.
Whether a rule merges or dedups will be up to the rules comparison
and merge methods.
Signed-off-by: John Johansen <john.johansen@canonical.com>
In preparation for rule comparison and elemination have each rule
carry a type that can be used as the base of comparison. The
rule class is folded into this type.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Instead of having each rule individually handle the class info
introduce a class_rule_t into the hierarchy and consolidate.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The post_process() method is misnamed, it fires when the profile is
finished parsing but fires before variable expansion. Rename it
to better reflect what it does and move the trigger code into
profile as a start of cleaning this stage up.
Also document the order the hooks fire in
Signed-off-by: John Johansen <john.johansen@canonical.com>
The previous patch enable the prefix based rules all to use the
same code pattern. Group them together
Signed-off-by: John Johansen <john.johansen@canonical.com>
Cleanup the parse code by making shared prefix and perms classes for
rules and convert rules to use them.
Signed-off-by: John Johansen <john.johansen@canonical.com>
This removes the struct wrapper used in the previous patch to ensure
that all uses are properly converted.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Audit control support is going to be extended to support allowing
policy to which rules should quiet auditing. Update the frontend
internals to prepare for this.
Signed-off-by: John Johansen <john.johansen@canonical.com>
This removes the struct wrapper used in the previous patch to ensure
that all uses are properly converted.
Signed-off-by: John Johansen <john.johansen@canonical.com>
This delays the convertion of the audit flag until passing to the
backend. This is a step towards fix the parser front end so that it
doesn't use encoded permission mappings.
Note: the patch embedds the bool conversion into a struct to ensure
the compiler will fail to build unless every use is fixed. The
struct is removed in the following patch.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Make mount permission set consistent with the other rule types. This
is a step towards refactoring.
Signed-off-by: John Johansen <john.johansen@canonical.com>
This is a step towards restructuring how "audit" is handled so we
can add quiet support and push mapping of audit bits later.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Move from using and int for permissions bit mask to a perms_t type.
Also move any perms mask that uses the name mode to perms to avoid
confusing it with other uses of mode.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Recent work on the parser has surfaced missing header dependencies
and other issues. Cleanup up and simplify the dependencies so it
is harder to break them.
Signed-off-by: John Johansen <john.johansen@canonical.com>
This is a partial fix for CVE-2016-1585, it address the frontend rule encoding problems particularly
- Permissions being given that shouldn't happen
- Multiple option conditionals in a single rule resulting in wider permission instead of multiple rules
- optional flags not being handled correctly
- multiple backend rules being created out of one frontend rule when they shouldn't be
it does not address the backend issue of short cut permissions not being correctly updated when deny rules carve out permissions on an allow rule that has a short cut permission in the encoding.
Thanks to the additional work by Alexander Mikhalitsyn for beating this MR into shape so we can land it
Alexander Changelog:
- rebased to an actual tree
- addressed review comments from @wbumiller and @setharnold
- fixed compiler warnings about class_mount_hdr is uninitialized
- infinite loop fix
- MS_MAKE_CMDS bitmask value fixed
- fixed condition in `gen_flag_rules` to cover cases like `mount options in (bind) /d -> /4,` when flags are empty and only opt_flags are present
- marked some tests as a FAIL case behavior was changed after `parser: add conflicting flags check for options= conditionals` commit
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/333
Approved-by: John Johansen <john@jjmx.net>
Merged-by: John Johansen <john@jjmx.net>
These tests contains incompatible mount options and broken
after ("parser: add conflicting flags check for options= conditionals")
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
gen_flag_rules has a boolean vs bit and case where parenthesis are
helpful to express the intended order of operations.
It also doesn't handle the case where there are no matches. Fix this
by causing that case to fail.
also improve the debug of option extraction.
Signed-off-by: John Johansen <john.johansen@canonical.com>
