kernel_optimize_test/security/selinux/ss
Ondrej Mosnacek fd75d73aa2 selinux: fix cond_list corruption when changing booleans
commit d8f5f0ea5b86300390b026b6c6e7836b7150814a upstream.

Currently, duplicate_policydb_cond_list() first copies the whole
conditional avtab and then tries to link to the correct entries in
cond_dup_av_list() using avtab_search(). However, since the conditional
avtab may contain multiple entries with the same key, this approach
often fails to find the right entry, potentially leading to wrong rules
being activated/deactivated when booleans are changed.

To fix this, instead start with an empty conditional avtab and add the
individual entries one-by-one while building the new av_lists. This
approach leads to the correct result, since each entry is present in the
av_lists exactly once.

The issue can be reproduced with Fedora policy as follows:

    # sesearch -s ftpd_t -t public_content_rw_t -c dir -p create -A
    allow ftpd_t non_security_file_type:dir { add_name create getattr ioctl link lock open read remove_name rename reparent rmdir search setattr unlink watch watch_reads write }; [ ftpd_full_access ]:True
    allow ftpd_t public_content_rw_t:dir { add_name create link remove_name rename reparent rmdir setattr unlink watch watch_reads write }; [ ftpd_anon_write ]:True
    # setsebool ftpd_anon_write=off ftpd_connect_all_unreserved=off ftpd_connect_db=off ftpd_full_access=off

On fixed kernels, the sesearch output is the same after the setsebool
command:

    # sesearch -s ftpd_t -t public_content_rw_t -c dir -p create -A
    allow ftpd_t non_security_file_type:dir { add_name create getattr ioctl link lock open read remove_name rename reparent rmdir search setattr unlink watch watch_reads write }; [ ftpd_full_access ]:True
    allow ftpd_t public_content_rw_t:dir { add_name create link remove_name rename reparent rmdir setattr unlink watch watch_reads write }; [ ftpd_anon_write ]:True

While on the broken kernels, it will be different:

    # sesearch -s ftpd_t -t public_content_rw_t -c dir -p create -A
    allow ftpd_t non_security_file_type:dir { add_name create getattr ioctl link lock open read remove_name rename reparent rmdir search setattr unlink watch watch_reads write }; [ ftpd_full_access ]:True
    allow ftpd_t non_security_file_type:dir { add_name create getattr ioctl link lock open read remove_name rename reparent rmdir search setattr unlink watch watch_reads write }; [ ftpd_full_access ]:True
    allow ftpd_t non_security_file_type:dir { add_name create getattr ioctl link lock open read remove_name rename reparent rmdir search setattr unlink watch watch_reads write }; [ ftpd_full_access ]:True

While there, also simplify the computation of nslots. This changes the
nslots values for nrules 2 or 3 to just two slots instead of 4, which
makes the sequence more consistent.

Cc: stable@vger.kernel.org
Fixes: c7c556f1e8 ("selinux: refactor changing booleans")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-14 08:41:57 +02:00
..
avtab.c selinux: fix cond_list corruption when changing booleans 2021-04-14 08:41:57 +02:00
avtab.h selinux: fix cond_list corruption when changing booleans 2021-04-14 08:41:57 +02:00
conditional.c selinux: fix cond_list corruption when changing booleans 2021-04-14 08:41:57 +02:00
conditional.h selinux: refactor changing booleans 2020-08-17 21:00:33 -04:00
constraint.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
context.c selinux: hash context structure directly 2020-04-17 16:04:34 -04:00
context.h selinux: move context hashing under sidtab 2020-04-17 16:04:38 -04:00
ebitmap.c selinux: hash context structure directly 2020-04-17 16:04:34 -04:00
ebitmap.h selinux: hash context structure directly 2020-04-17 16:04:34 -04:00
hashtab.c selinux: refactor changing booleans 2020-08-17 21:00:33 -04:00
hashtab.h selinux: refactor changing booleans 2020-08-17 21:00:33 -04:00
mls_types.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mls.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
mls.h selinux: hash context structure directly 2020-04-17 16:04:34 -04:00
policydb.c selinux: prepare for inlining of hashtab functions 2020-07-09 19:05:36 -04:00
policydb.h selinux: prepare for inlining of hashtab functions 2020-07-09 19:05:36 -04:00
services.c selinux: fix variable scope issue in live sidtab conversion 2021-03-30 14:31:53 +02:00
services.h selinux: convert policy read-write lock to RCU 2020-08-25 08:34:47 -04:00
sidtab.c selinux: move policy commit after updating selinuxfs 2020-08-17 20:50:22 -04:00
sidtab.h selinux: move policy commit after updating selinuxfs 2020-08-17 20:50:22 -04:00
symtab.c selinux: prepare for inlining of hashtab functions 2020-07-09 19:05:36 -04:00
symtab.h selinux: specialize symtab insert and search functions 2020-07-08 20:21:43 -04:00