While fuzzing hll/pp, the fuzzer (AFL) crafted a policy which triggered
the following message without making the policy loading fail (the
program crashed with a segmentation fault later):
security: ebitmap: map size 192 does not match my size 64 (high bit
was 0)
This is because ebitmap_read() returned -EINVAL and this value was
handled as a successful return value by scope_index_read() because it
was not -1.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
When fuzzing hll/pp inputs, a policy module where the value of
scope->decl_ids_len has been modified to zero makes the program abort
(when it has been compiled without -DNDEBUG).
Change the behavior to report an error message instead. This eases
fuzzing functions like policydb_read().
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
The combining logic for dontaudit rules was wrong, causing
a dontaudit A B:C *; rule to be clobbered by a dontaudit A B:C p;
rule.
This is a reimplementation of:
commit 6201bb5e25 ("libsepol:
fix checkpolicy dontaudit compiler bug")
that avoids the cumbersome pointer assignments on alloced.
Reported-by: Nick Kralevich <nnk@google.com>
Signed-off-by: William Roberts <william.c.roberts@intel.com>
The flex skeleton often triggers compiler warnings; make these
non-fatal for building. We already do likewise for checkpolicy.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
The combining logic for dontaudit rules was wrong, causing
a dontaudit A B:C *; rule to be clobbered by a dontaudit A B:C p;
rule.
Reported-by: Nick Kralevich <nnk@google.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
The sepol_{bool|iface|user}_key_create() functions were not
copying the name. This produces a use-after-free in the
swig-generated code for python3 bindings. Copy the name
in these functions, and free it upon sepol_{bool|iface|user}_key_free().
Reported-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Nicholas Iooss discovered that using an unknown permission with a
map class will cause a segfault.
CIL will only give a warning when it fails to resolve an unknown
permission to support the use of policy module packages that use
permissions that don't exit on the current system. When resolving
the unknown map class permission an empty list is used to represent
the unknown permission. When it is evaluated later the list is
assumed to be a permission and a segfault occurs.
There is no reason to allow unknown class map permissions because
the class maps and permissions are defined by the policy.
Exit with an error when failing to resolve a class map permission.
Reported-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
The blank default symver fails to compile with ld.gold. This updates the
symver from blank to LIBSEPOL_1.0. The dynamic linker will first look
for the symbol with the explicit version specified. If there is none, it
will pick the first listed symbol so there is no breakage.
This also matches how symvers are defined in libsemanage.
Signed-off-by: Jason Zaman <jason@perfinion.com>
cil_strpool currently provides an interface to a statically stored
global data structure. This interface does not accomodate multiple
consumers, however, as two calls to cil_strpool_init() will lead to a
memory leak and a call to cil_strpool_destroy() by one consumer will
remove data from use by others, and subsequently lead to a segfault on
the next cil_strpool_destroy() invocation.
Add a reference counter so that the strpool is only initialized once and
protect the exported interface with a mutex.
Tested by calling cil_db_init() on two cil_dbs and then calling
cil_db_destroy() on each.
Signed-off-by: Daniel Cashman <dcashman@android.com>
Nicolas Iooss found while fuzzing secilc with AFL that using an attribute
as a child in a typebounds statement will cause a segfault.
This happens because the child datum is assumed to be part of a cil_type
struct when it is really part of a cil_typeattribute struct. The check to
verify that it is a type and not an attribute comes after it is used.
This bug effects user and role bounds as well because they do not check
whether a datum refers to an attribute or not.
Add checks to verify that neither the child nor the parent datum refer
to an attribute before using them in user, role, and type bounds.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Nicolas Iooss found while fuzzing secilc with AFL that the statement
"(sensitivityaliasactual SENS SENS)" will cause a segfault.
The segfault occurs because when the aliasactual is resolved the first
identifier is assumed to refer to an alias structure, but it is not.
Add a check to verify that the datum retrieved is actually an alias
and exit with an error if it is not.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Nicolas Iooss found while fuzzing secilc with AFL that the statement
"(class C (()))" will cause a segfault.
CIL expects a list of permissions in the class declaration and "(())"
is a valid list. Each item of the list is expected to be an identifier
and as the list is processed each item is checked to see if it is a
list. An error is given if it is a list, otherwise the item is assumed
to be an identifier. Unfortunately, the check only works if the list
is not empty. In this case, the item passes the check and is assumed
to be an identifier and a NULL is passed as the string for name
verification. If name verification assumes that a non-NULL value will
be passed in, a segfault will occur.
Add a check for an empty list when processing a permission list and
improve the error handling for permissions when building the AST.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Nicolas Iooss found while fuzzing secilc with AFL that the statement
"(class C (()))" will cause a segfault.
When CIL checks the syntax of the class statement it sees "(())" as a
valid permission list, but since "()" is not an identifier a NULL is
passed as the string for name verification. A segfault occurs because
name verification assumes that the string being checked is non-NULL.
Check if identifier is NULL when verifying name.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Nicolas Iooss found while fuzzing secilc with AFL that the statement
"(classpermissionset CPERM (CLASS (and unknow PERM)))" will cause a
segfault.
In order to support a policy module package using a permission that
does not exist on the system it is loaded on, CIL will only give a
warning when it fails to resolve an unknown permission. CIL itself will
just ignore the unknown permission. This means that an expression like
"(and UNKNOWN p1)" will look like "(and p1)" to CIL, but, since syntax
checking has already been done, CIL won't know that the expression is not
well-formed. When the expression is evaluated a segfault will occur
because all expressions are assumed to be well-formed at evaluation time.
Use an empty list to represent an unknown permission so that expressions
will continue to be well-formed and expression evaluation will work but
the unknown permission will still be ignored.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Nicolas Iooss found while fuzzing secilc with AFL that the following
policy will cause a segfault.
(category c0)
(category c1)
(categoryorder (c0 c1))
(sensitivity s0)
(sensitivitycategory s0 (not (all)))
The expression "(not (all))" is evaluated as containing no categories.
There is a check for the resulting empty list and the category datum
expression is set to NULL. The segfault occurs because the datum
expression is assumed to be non-NULL after evaluation.
Assign the list to the datum expression even if it is empty.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Nicolas Iooss found while fuzzing secilc with AFL that the following
policy will cause a segfault.
(category c0)
(category c1)
(categoryorder (c0 c1))
(sensitivity s0)
(sensitivitycategory s0 (range c1 c0))
The category range "(range c1 c0)" is invalid because c1 comes after c0
in order.
The invalid range is evaluated as containing no categories. There is a
check for the resulting empty list and the category datum expression is
set to NULL. The segfault occurs because the datum expression is assumed
to be non-NULL after evaluation.
Add a check for an invalid range when evaluating category ranges.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Correct the build issues on mac, mostly flags for tools.
libsepol and cil now build completley on Mac with a
simple make command.
Signed-off-by: William Roberts <william.c.roberts@intel.com>
The local: * entry should only be in the base entry, not in each of them.
This is part of resolving gold linker build failures reported by
Jason Zaman.
Reported-by: Jason Zaman <jason@perfinion.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
__cil_fill_expr() initializes 'cil_list *sub_expr' but does not destroy
it when __cil_fill_expr_helper() fails. This list is therefore leaked
when __cil_fill_expr() returns.
This occurs when secilc compiles the following policy:
(class CLASS (PERM))
(classorder (CLASS))
(sid SID)
(sidorder (SID))
(user USER)
(role ROLE)
(type TYPE)
(category CAT)
(categoryorder (CAT))
(sensitivity SENS)
(sensitivityorder (SENS))
(sensitivitycategory SENS (CAT))
(allow TYPE self (CLASS (PERM)))
(roletype ROLE TYPE)
(userrole USER ROLE)
(userlevel USER (SENS))
(userrange USER ((SENS)(SENS (CAT))))
(sidcontext SID (USER ROLE TYPE ((SENS)(SENS))))
(categoryset cats (not (range unknown)))
This bug has been found using gcc address sanitizer.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
When cil_fill_cats() fails to parse an expression and destroys a
category set, it fails to reset *cats to NULL. This makes this object be
destroyed again in cil_destroy_catset().
This bug can be triggered by the following policy:
(class CLASS (PERM))
(classorder (CLASS))
(sid SID)
(sidorder (SID))
(user USER)
(role ROLE)
(type TYPE)
(category CAT)
(categoryorder (CAT))
(sensitivity SENS)
(sensitivityorder (SENS))
(sensitivitycategory SENS (CAT))
(allow TYPE self (CLASS (PERM)))
(roletype ROLE TYPE)
(userrole USER ROLE)
(userlevel USER (SENS))
(userrange USER ((SENS)(SENS (CAT))))
(sidcontext SID (USER ROLE TYPE ((SENS)(SENS))))
(categoryset cats (range unknown))
This bug has been found by fuzzing secilc with american fuzzy lop.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
This CIL policy makes secilc crash with a NULL pointer dereference:
(class CLASS (PERM))
(classorder (CLASS))
(sid SID)
(sidorder (SID))
(user USER)
(role ROLE)
(type TYPE)
(category CAT)
(categoryorder (CAT))
(sensitivity SENS)
(sensitivityorder (SENS))
(sensitivitycategory SENS (CAT))
(allow TYPE self (CLASS (PERM)))
(roletype ROLE TYPE)
(userrole USER ROLE)
(userlevel USER (SENS))
(userrange USER ((SENS)(SENS (CAT))))
(sidcontext SID (USER ROLE TYPE ((SENS)(SENS))))
(allow . self (CLASS (PERM)))
Using "." in the allow statement makes strtok_r() return NULL in
cil_resolve_name() and this result is then used in a call to
cil_symtab_get_datum(), which is thus invalid.
Instead of crashing, make secilc fail with an error message.
This bug has been found by fuzzing secilc with american fuzzy lop.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Checkpolicy has an option to produce CIL output and is dependent on
the policydb-to-CIL conversion in libsepol for that option. Add
support for converting extended permissions to CIL so that checlpolicy
can generate CIL.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Pre-expands the role and user caches used in context validation when
conerting a cildb to a binary policydb. This is currently only done
when loading a binary policy and prevents context validation from
working correctly with a newly built policy (i.e., when semanage builds
a new policy and then runs genhomedircon).
Also adds declarations for the hashtable mapping functions used:
policydb_role_cache and policydb_user_cache().
Signed-off-by: Gary Tierney <gary.tierney@gmx.com>
Fixes bug found by Nicolas Iooss as described below in the way suggested by Steve Lawrence.
Nicolass reported:
When compiling a CIL policy with more than 32 items in a class (e.g. in
(class capability (chown ...)) with many items),
cil_classorder_to_policydb() overflows perm_value_to_cil[class_index]
array. As this array is allocated on the heap through
calloc(PERMS_PER_CLASS+1, sizeof(...)), this makes secilc crash with the
following message:
*** Error in `/usr/bin/secilc': double free or corruption (!prev): 0x000000000062be80 ***
======= Backtrace: =========
/usr/lib/libc.so.6(+0x70c4b)[0x7ffff76a7c4b]
/usr/lib/libc.so.6(+0x76fe6)[0x7ffff76adfe6]
/usr/lib/libc.so.6(+0x777de)[0x7ffff76ae7de]
/lib/libsepol.so.1(+0x14fbda)[0x7ffff7b24bda]
/lib/libsepol.so.1(+0x152db8)[0x7ffff7b27db8]
/lib/libsepol.so.1(cil_build_policydb+0x63)[0x7ffff7af8723]
/usr/bin/secilc[0x40273b]
/usr/lib/libc.so.6(__libc_start_main+0xf1)[0x7ffff7657291]
/usr/bin/secilc[0x402f7a]
This bug has been found by fuzzing secilc with american fuzzy lop.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Commit 915fa8f08f moves the xperm specified value directly from
avrule to avtab. The mapping between them is currently the same,
but may not always be. Instead these values should be mapped using
values defined in av_extended_perms_t and avtab_extended_perms_t.
Fixes: 915fa8f08f ("checkpolicy: switch operations to extended perms")
Change-Id: Ic9f4031c9381b2ff6cc46043fb1602758ef4c224
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
