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* | | Merge tag 'selinux-pr-20220321' of ↵Linus Torvalds2022-03-2118-212/+201
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "We've got a number of SELinux patches queued up, the highlights are: - Fixup the security_fs_context_parse_param() LSM hook so it executes all of the LSM hook implementations unless a serious error occurs. We also correct the SELinux hook implementation so that it returns zero on success. - In addition to a few SELinux mount option parsing fixes, we simplified the parsing by moving it earlier in the process. The logic was that it was unlikely an admin/user would use the new mount API and not have the policy loaded before passing the SELinux options. - Properly fixed the LSM/SELinux/SCTP hooks with the addition of the security_sctp_assoc_established() hook. This work was done in conjunction with the netdev folks and should complete the move of the SCTP labeling from the endpoints to the associations. - Fixed a variety of sparse warnings caused by changes in the "__rcu" markings of some core kernel structures. - Ensure we access the superblock's LSM security blob using the stacking-safe accessors. - Added the ability for the kernel to always allow FIOCLEX and FIONCLEX if the "ioctl_skip_cloexec" policy capability is specified. - Various constifications improvements, type casting improvements, additional return value checks, and dead code/parameter removal. - Documentation fixes" * tag 'selinux-pr-20220321' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: (23 commits) selinux: shorten the policy capability enum names docs: fix 'make htmldocs' warning in SCTP.rst selinux: allow FIOCLEX and FIONCLEX with policy capability selinux: use correct type for context length selinux: drop return statement at end of void functions security: implement sctp_assoc_established hook in selinux security: add sctp_assoc_established hook selinux: parse contexts for mount options early selinux: various sparse fixes selinux: try to use preparsed sid before calling parse_sid() selinux: Fix selinux_sb_mnt_opts_compat() LSM: general protection fault in legacy_parse_param selinux: fix a type cast problem in cred_init_security() selinux: drop unused macro selinux: simplify cred_init_security selinux: do not discard const qualifier in cast selinux: drop unused parameter of avtab_insert_node selinux: drop cast to same type selinux: enclose macro arguments in parenthesis selinux: declare name parameter of hash_eval const ...
| * | selinux: shorten the policy capability enum namesPaul Moore2022-03-025-24/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The SELinux policy capability enum names are rather long and follow the "POLICYDB_CAPABILITY_XXX format". While the "POLICYDB_" prefix is helpful in tying the enums to other SELinux policy constants, macros, etc. there is no reason why we need to spell out "CAPABILITY" completely. Shorten "CAPABILITY" to "CAP" in order to make things a bit shorter and cleaner. Moving forward, the SELinux policy capability enum names should follow the "POLICYDB_CAP_XXX" format. Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: allow FIOCLEX and FIONCLEX with policy capabilityRichard Haines2022-02-254-1/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These ioctls are equivalent to fcntl(fd, F_SETFD, flags), which SELinux always allows too. Furthermore, a failed FIOCLEX could result in a file descriptor being leaked to a process that should not have access to it. As this patch removes access controls, a policy capability needs to be enabled in policy to always allow these ioctls. Based-on-patch-by: Demi Marie Obenour <demiobenour@gmail.com> Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> [PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: use correct type for context lengthChristian Göttsche2022-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | security_sid_to_context() expects a pointer to an u32 as the address where to store the length of the computed context. Reported by sparse: security/selinux/xfrm.c:359:39: warning: incorrect type in arg 4 (different signedness) security/selinux/xfrm.c:359:39: expected unsigned int [usertype] *scontext_len security/selinux/xfrm.c:359:39: got int * Signed-off-by: Christian Göttsche <cgzones@googlemail.com> [PM: wrapped commit description] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: drop return statement at end of void functionsChristian Göttsche2022-02-185-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | Those return statements at the end of a void function are redundant. Reported by clang-tidy [readability-redundant-control-flow] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | security: implement sctp_assoc_established hook in selinuxOndrej Mosnacek2022-02-151-24/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do this by extracting the peer labeling per-association logic from selinux_sctp_assoc_request() into a new helper selinux_sctp_process_new_assoc() and use this helper in both selinux_sctp_assoc_request() and selinux_sctp_assoc_established(). This ensures that the peer labeling behavior as documented in Documentation/security/SCTP.rst is applied both on the client and server side: """ An SCTP socket will only have one peer label assigned to it. This will be assigned during the establishment of the first association. Any further associations on this socket will have their packet peer label compared to the sockets peer label, and only if they are different will the ``association`` permission be validated. This is validated by checking the socket peer sid against the received packets peer sid to determine whether the association should be allowed or denied. """ At the same time, it also ensures that the peer label of the association is set to the correct value, such that if it is peeled off into a new socket, the socket's peer label will then be set to the association's peer label, same as it already works on the server side. While selinux_inet_conn_established() (which we are replacing by selinux_sctp_assoc_established() for SCTP) only deals with assigning a peer label to the connection (socket), in case of SCTP we need to also copy the (local) socket label to the association, so that selinux_sctp_sk_clone() can then pick it up for the new socket in case of SCTP peeloff. Careful readers will notice that the selinux_sctp_process_new_assoc() helper also includes the "IPv4 packet received over an IPv6 socket" check, even though it hadn't been in selinux_sctp_assoc_request() before. While such check is not necessary in selinux_inet_conn_request() (because struct request_sock's family field is already set according to the skb's family), here it is needed, as we don't have request_sock and we take the initial family from the socket. In selinux_sctp_assoc_established() it is similarly needed as well (and also selinux_inet_conn_established() already has it). Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Based-on-patch-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: parse contexts for mount options earlyOndrej Mosnacek2022-02-041-149/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit b8b87fd954b4 ("selinux: Fix selinux_sb_mnt_opts_compat()") started to parse mount options into SIDs in selinux_add_opt() if policy has already been loaded. Since it's extremely unlikely that anyone would depend on the ability to set SELinux contexts on fs_context before loading the policy and then mounting that context after simplify the logic by always parsing the options early. Note that the multi-step mounting is only possible with the new fscontext mount API and wasn't possible before its introduction. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: various sparse fixesPaul Moore2022-02-014-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | When running the SELinux code through sparse, there are a handful of warnings. This patch resolves some of these warnings caused by "__rcu" mismatches. % make W=1 C=1 security/selinux/ Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: try to use preparsed sid before calling parse_sid()Scott Mayhew2022-02-011-29/+59
| | | | | | | | | | | | | | | | | | | | | | | | Avoid unnecessary parsing of sids that have already been parsed via selinux_sb_eat_lsm_opts(). Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: Fix selinux_sb_mnt_opts_compat()Scott Mayhew2022-02-011-34/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | selinux_sb_mnt_opts_compat() is called under the sb_lock spinlock and shouldn't be performing any memory allocations. Fix this by parsing the sids at the same time we're chopping up the security mount options string and then using the pre-parsed sids when doing the comparison. Fixes: cc274ae7763d ("selinux: fix sleeping function called from invalid context") Fixes: 69c4a42d72eb ("lsm,selinux: add new hook to compare new mount to an existing mount") Signed-off-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | LSM: general protection fault in legacy_parse_paramCasey Schaufler2022-01-271-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The usual LSM hook "bail on fail" scheme doesn't work for cases where a security module may return an error code indicating that it does not recognize an input. In this particular case Smack sees a mount option that it recognizes, and returns 0. A call to a BPF hook follows, which returns -ENOPARAM, which confuses the caller because Smack has processed its data. The SELinux hook incorrectly returns 1 on success. There was a time when this was correct, however the current expectation is that it return 0 on success. This is repaired. Reported-by: syzbot+d1e3b1d92d25abf97943@syzkaller.appspotmail.com Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: fix a type cast problem in cred_init_security()Paul Moore2022-01-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the process of removing an explicit type cast to preserve a cred const qualifier in cred_init_security() we ran into a problem where the task_struct::real_cred field is defined with the "__rcu" attribute but the selinux_cred() function parameter is not, leading to a sparse warning: security/selinux/hooks.c:216:36: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct cred const *cred @@ got struct cred const [noderef] __rcu *real_cred As we don't want to add the "__rcu" attribute to the selinux_cred() parameter, we're going to add an explicit cast back to cred_init_security(). Fixes: b084e189b01a ("selinux: simplify cred_init_security") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: drop unused macroChristian Göttsche2022-01-261-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The macro _DEBUG_HASHES is nowhere used. The configuration DEBUG_HASHES enables debugging of the SELinux hash tables, but the with an underscore prefixed macro definition has no direct impact or any documentation. Reported by clang [-Wunused-macros] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: simplify cred_init_securityChristian Göttsche2022-01-261-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The parameter of selinux_cred() is declared const, so an explicit cast dropping the const qualifier is not necessary. Without the cast the local variable cred serves no purpose. Reported by clang [-Wcast-qual] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: do not discard const qualifier in castChristian Göttsche2022-01-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do not discard the const qualifier on the cast from const void* to __be32*; the addressed value is not modified. Reported by clang [-Wcast-qual] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: drop unused parameter of avtab_insert_nodeChristian Göttsche2022-01-261-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | The parameter cur is not used in avtab_insert_node(). Reported by clang [-Wunused-parameter] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: drop cast to same typeChristian Göttsche2022-01-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both the lvalue scontextp and rvalue scontext are of the type char*. Drop the redundant explicit cast not needed since commit 9a59daa03df7 ("SELinux: fix sleeping allocation in security_context_to_sid"), where the type of scontext changed from const char* to char*. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: enclose macro arguments in parenthesisChristian Göttsche2022-01-263-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enclose the macro arguments in parenthesis to avoid potential evaluation order issues. Note the xperm and ebitmap macros are still not side-effect safe due to double evaluation. Reported by clang-tidy [bugprone-macro-parentheses] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: declare name parameter of hash_eval constChristian Göttsche2022-01-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | String literals are passed as second argument to hash_eval(). Also the parameter is already declared const in the DEBUG_HASHES configuration. Reported by clang [-Wwrite-strings]: security/selinux/ss/policydb.c:1881:26: error: passing 'const char [8]' to parameter of type 'char *' discards qualifiers hash_eval(&p->range_tr, rangetr); ^~~~~~~~~ security/selinux/ss/policydb.c:707:55: note: passing argument to parameter 'hash_name' here static inline void hash_eval(struct hashtab *h, char *hash_name) ^ security/selinux/ss/policydb.c:2099:32: error: passing 'const char [11]' to parameter of type 'char *' discards qualifiers hash_eval(&p->filename_trans, filenametr); ^~~~~~~~~~~~ security/selinux/ss/policydb.c:707:55: note: passing argument to parameter 'hash_name' here static inline void hash_eval(struct hashtab *h, char *hash_name) ^ Signed-off-by: Christian Göttsche <cgzones@googlemail.com> [PM: line wrapping in description] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: declare path parameters of _genfs_sid constChristian Göttsche2022-01-252-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The path parameter is only read from in security_genfs_sid(), selinux_policy_genfs_sid() and __security_genfs_sid(). Since a string literal is passed as argument, declare the parameter const. Also align the parameter names in the declaration and definition. Reported by clang [-Wwrite-strings]: security/selinux/hooks.c:553:60: error: passing 'const char [2]' to parameter of type 'char *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers] rc = security_genfs_sid(&selinux_state, ... , /, ^~~ ./security/selinux/include/security.h:389:36: note: passing argument to parameter 'name' here const char *fstype, char *name, u16 sclass, ^ Signed-off-by: Christian Göttsche <cgzones@googlemail.com> [PM: wrapped description] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: check return value of sel_make_avc_filesChristian Göttsche2022-01-251-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sel_make_avc_files() might fail and return a negative errno value on memory allocation failures. Re-add the check of the return value, dropped in 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table"). Reported by clang-analyzer: security/selinux/selinuxfs.c:2129:2: warning: Value stored to 'ret' is never read [deadcode.DeadStores] ret = sel_make_avc_files(dentry); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~ Fixes: 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table") Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> [PM: description line wrapping, added proper commit ref] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * | selinux: access superblock_security_struct in LSM blob wayGONG, Ruiqi2022-01-251-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | LSM blob has been involved for superblock's security struct. So fix the remaining direct access to sb->s_security by using the LSM blob mechanism. Fixes: 08abe46b2cfc ("selinux: fall back to SECURITY_FS_USE_GENFS if no xattr support") Fixes: 69c4a42d72eb ("lsm,selinux: add new hook to compare new mount to an existing mount") Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: fix misuse of mutex_is_locked()Ondrej Mosnacek2022-02-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | mutex_is_locked() tests whether the mutex is locked *by any task*, while here we want to test if it is held *by the current task*. To avoid false/missed WARNINGs, use lockdep_assert_is_held() and lockdep_assert_is_not_held() instead, which do the right thing (though they are a no-op if CONFIG_LOCKDEP=n). Cc: stable@vger.kernel.org Fixes: 2554a48f4437 ("selinux: measure state and policy capabilities") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: fix double free of cond_list on error pathsVratislav Bendel2022-02-021-1/+2
|/ | | | | | | | | | | | | | | On error path from cond_read_list() and duplicate_policydb_cond_list() the cond_list_destroy() gets called a second time in caller functions, resulting in NULL pointer deref. Fix this by resetting the cond_list_len to 0 in cond_list_destroy(), making subsequent calls a noop. Also consistently reset the cond_list pointer to NULL after freeing. Cc: stable@vger.kernel.org Signed-off-by: Vratislav Bendel <vbendel@redhat.com> [PM: fix line lengths in the description] Signed-off-by: Paul Moore <paul@paul-moore.com>
* Merge tag 'selinux-pr-20220110' of ↵Linus Torvalds2022-01-113-66/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "Nothing too significant, but five SELinux patches for v5.17 that do the following: - Harden the code through additional use of the struct_size() macro - Plug some memory leaks - Clean up the code via removal of the security_add_mnt_opt() LSM hook and minor tweaks to selinux_add_opt() - Rename security_task_getsecid_subj() to better reflect its actual behavior/use - now called security_current_getsecid_subj()" * tag 'selinux-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: minor tweaks to selinux_add_opt() selinux: fix potential memleak in selinux_add_opt() security,selinux: remove security_add_mnt_opt() selinux: Use struct_size() helper in kmalloc() lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()
| * selinux: minor tweaks to selinux_add_opt()Paul Moore2021-12-211-8/+10
| | | | | | | | | | | | | | | | Two minor edits to selinux_add_opt(): use "sizeof(*ptr)" instead of "sizeof(type)" in the kzalloc() call, and rename the "Einval" jump target to "err" for the sake of consistency. Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: fix potential memleak in selinux_add_opt()Bernard Zhao2021-12-211-2/+10
| | | | | | | | | | | | | | | | | | This patch try to fix potential memleak in error branch. Fixes: ba6418623385 ("selinux: new helper - selinux_add_opt()") Signed-off-by: Bernard Zhao <bernard@vivo.com> [PM: tweak the subject line, add Fixes tag] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * security,selinux: remove security_add_mnt_opt()Ondrej Mosnacek2021-12-061-39/+0
| | | | | | | | | | | | | | | | | | Its last user has been removed in commit f2aedb713c28 ("NFS: Add fs_context support."). Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: Use struct_size() helper in kmalloc()Xiu Jianfeng2021-12-052-3/+3
| | | | | | | | | | | | | | | | Make use of struct_size() helper instead of an open-coded calculation. Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()Paul Moore2021-11-221-16/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The security_task_getsecid_subj() LSM hook invites misuse by allowing callers to specify a task even though the hook is only safe when the current task is referenced. Fix this by removing the task_struct argument to the hook, requiring LSM implementations to use the current task. While we are changing the hook declaration we also rename the function to security_current_getsecid_subj() in an effort to reinforce that the hook captures the subjective credentials of the current task and not an arbitrary task on the system. Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: initialize proto variable in selinux_ip_postroute_compat()Tom Rix2021-12-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clang static analysis reports this warning hooks.c:5765:6: warning: 4th function call argument is an uninitialized value if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ selinux_parse_skb() can return ok without setting proto. The later call to selinux_xfrm_postroute_last() does an early check of proto and can return ok if the garbage proto value matches. So initialize proto. Cc: stable@vger.kernel.org Fixes: eef9b41622f2 ("selinux: cleanup selinux_xfrm_sock_rcv_skb() and selinux_xfrm_postroute_last()") Signed-off-by: Tom Rix <trix@redhat.com> [PM: typo/spelling and checkpatch.pl description fixes] Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: fix sleeping function called from invalid contextScott Mayhew2021-12-161-14/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | selinux_sb_mnt_opts_compat() is called via sget_fc() under the sb_lock spinlock, so it can't use GFP_KERNEL allocations: [ 868.565200] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:230 [ 868.568246] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 4914, name: mount.nfs [ 868.569626] preempt_count: 1, expected: 0 [ 868.570215] RCU nest depth: 0, expected: 0 [ 868.570809] Preemption disabled at: [ 868.570810] [<0000000000000000>] 0x0 [ 868.571848] CPU: 1 PID: 4914 Comm: mount.nfs Kdump: loaded Tainted: G W 5.16.0-rc5.2585cf9dfa #1 [ 868.573273] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 [ 868.574478] Call Trace: [ 868.574844] <TASK> [ 868.575156] dump_stack_lvl+0x34/0x44 [ 868.575692] __might_resched.cold+0xd6/0x10f [ 868.576308] slab_pre_alloc_hook.constprop.0+0x89/0xf0 [ 868.577046] __kmalloc_track_caller+0x72/0x420 [ 868.577684] ? security_context_to_sid_core+0x48/0x2b0 [ 868.578569] kmemdup_nul+0x22/0x50 [ 868.579108] security_context_to_sid_core+0x48/0x2b0 [ 868.579854] ? _nfs4_proc_pathconf+0xff/0x110 [nfsv4] [ 868.580742] ? nfs_reconfigure+0x80/0x80 [nfs] [ 868.581355] security_context_str_to_sid+0x36/0x40 [ 868.581960] selinux_sb_mnt_opts_compat+0xb5/0x1e0 [ 868.582550] ? nfs_reconfigure+0x80/0x80 [nfs] [ 868.583098] security_sb_mnt_opts_compat+0x2a/0x40 [ 868.583676] nfs_compare_super+0x113/0x220 [nfs] [ 868.584249] ? nfs_try_mount_request+0x210/0x210 [nfs] [ 868.584879] sget_fc+0xb5/0x2f0 [ 868.585267] nfs_get_tree_common+0x91/0x4a0 [nfs] [ 868.585834] vfs_get_tree+0x25/0xb0 [ 868.586241] fc_mount+0xe/0x30 [ 868.586605] do_nfs4_mount+0x130/0x380 [nfsv4] [ 868.587160] nfs4_try_get_tree+0x47/0xb0 [nfsv4] [ 868.587724] vfs_get_tree+0x25/0xb0 [ 868.588193] do_new_mount+0x176/0x310 [ 868.588782] __x64_sys_mount+0x103/0x140 [ 868.589388] do_syscall_64+0x3b/0x90 [ 868.589935] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 868.590699] RIP: 0033:0x7f2b371c6c4e [ 868.591239] Code: 48 8b 0d dd 71 0e 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d aa 71 0e 00 f7 d8 64 89 01 48 [ 868.593810] RSP: 002b:00007ffc83775d88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 868.594691] RAX: ffffffffffffffda RBX: 00007ffc83775f10 RCX: 00007f2b371c6c4e [ 868.595504] RDX: 0000555d517247a0 RSI: 0000555d51724700 RDI: 0000555d51724540 [ 868.596317] RBP: 00007ffc83775f10 R08: 0000555d51726890 R09: 0000555d51726890 [ 868.597162] R10: 0000000000000000 R11: 0000000000000246 R12: 0000555d51726890 [ 868.598005] R13: 0000000000000003 R14: 0000555d517246e0 R15: 0000555d511ac925 [ 868.598826] </TASK> Cc: stable@vger.kernel.org Fixes: 69c4a42d72eb ("lsm,selinux: add new hook to compare new mount to an existing mount") Signed-off-by: Scott Mayhew <smayhew@redhat.com> [PM: cleanup/line-wrap the backtrace] Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: fix NULL-pointer dereference when hashtab allocation failsOndrej Mosnacek2021-11-191-5/+12
|/ | | | | | | | | | | | | | | | | When the hash table slot array allocation fails in hashtab_init(), h->size is left initialized with a non-zero value, but the h->htable pointer is NULL. This may then cause a NULL pointer dereference, since the policydb code relies on the assumption that even after a failed hashtab_init(), hashtab_map() and hashtab_destroy() can be safely called on it. Yet, these detect an empty hashtab only by looking at the size. Fix this by making sure that hashtab_init() always leaves behind a valid empty hashtab when the allocation fails. Cc: stable@vger.kernel.org Fixes: 03414a49ad5f ("selinux: do not allocate hashtabs dynamically") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* net,lsm,selinux: revert the security_sctp_assoc_established() hookPaul Moore2021-11-121-13/+1
| | | | | | | | | | | | | | | | | | | | | This patch reverts two prior patches, e7310c94024c ("security: implement sctp_assoc_established hook in selinux") and 7c2ef0240e6a ("security: add sctp_assoc_established hook"), which create the security_sctp_assoc_established() LSM hook and provide a SELinux implementation. Unfortunately these two patches were merged without proper review (the Reviewed-by and Tested-by tags from Richard Haines were for previous revisions of these patches that were significantly different) and there are outstanding objections from the SELinux maintainers regarding these patches. Work is currently ongoing to correct the problems identified in the reverted patches, as well as others that have come up during review, but it is unclear at this point in time when that work will be ready for inclusion in the mainline kernel. In the interest of not keeping objectionable code in the kernel for multiple weeks, and potentially a kernel release, we are reverting the two problematic patches. Signed-off-by: Paul Moore <paul@paul-moore.com>
* security: implement sctp_assoc_established hook in selinuxXin Long2021-11-031-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Different from selinux_inet_conn_established(), it also gives the secid to asoc->peer_secid in selinux_sctp_assoc_established(), as one UDP-type socket may have more than one asocs. Note that peer_secid in asoc will save the peer secid for this asoc connection, and peer_sid in sksec will just keep the peer secid for the latest connection. So the right use should be do peeloff for UDP-type socket if there will be multiple asocs in one socket, so that the peeloff socket has the right label for its asoc. v1->v2: - call selinux_inet_conn_established() to reduce some code duplication in selinux_sctp_assoc_established(), as Ondrej suggested. - when doing peeloff, it calls sock_create() where it actually gets secid for socket from socket_sockcreate_sid(). So reuse SECSID_WILD to ensure the peeloff socket keeps using that secid after calling selinux_sctp_sk_clone() for client side. Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Reviewed-by: Richard Haines <richard_c_haines@btinternet.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* security: pass asoc to sctp_assoc_request and sctp_sk_cloneXin Long2021-11-033-22/+22
| | | | | | | | | | | | | | | | | | | | | | | This patch is to move secid and peer_secid from endpoint to association, and pass asoc to sctp_assoc_request and sctp_sk_clone instead of ep. As ep is the local endpoint and asoc represents a connection, and in SCTP one sk/ep could have multiple asoc/connection, saving secid/peer_secid for new asoc will overwrite the old asoc's. Note that since asoc can be passed as NULL, security_sctp_assoc_request() is moved to the place right after the new_asoc is created in sctp_sf_do_5_1B_init() and sctp_sf_do_unexpected_init(). v1->v2: - fix the description of selinux_netlbl_skbuff_setsid(), as Jakub noticed. - fix the annotation in selinux_sctp_assoc_request(), as Richard Noticed. Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Reviewed-by: Richard Haines <richard_c_haines@btinternet.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge tag 'selinux-pr-20211101' of ↵Linus Torvalds2021-11-018-244/+202
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: - Add LSM/SELinux/Smack controls and auditing for io-uring. As usual, the individual commit descriptions have more detail, but we were basically missing two things which we're adding here: + establishment of a proper audit context so that auditing of io-uring ops works similarly to how it does for syscalls (with some io-uring additions because io-uring ops are *not* syscalls) + additional LSM hooks to enable access control points for some of the more unusual io-uring features, e.g. credential overrides. The additional audit callouts and LSM hooks were done in conjunction with the io-uring folks, based on conversations and RFC patches earlier in the year. - Fixup the binder credential handling so that the proper credentials are used in the LSM hooks; the commit description and the code comment which is removed in these patches are helpful to understand the background and why this is the proper fix. - Enable SELinux genfscon policy support for securityfs, allowing improved SELinux filesystem labeling for other subsystems which make use of securityfs, e.g. IMA. * tag 'selinux-pr-20211101' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: security: Return xattr name from security_dentry_init_security() selinux: fix a sock regression in selinux_ip_postroute_compat() binder: use cred instead of task for getsecid binder: use cred instead of task for selinux checks binder: use euid from cred instead of using task LSM: Avoid warnings about potentially unused hook variables selinux: fix all of the W=1 build warnings selinux: make better use of the nf_hook_state passed to the NF hooks selinux: fix race condition when computing ocontext SIDs selinux: remove unneeded ipv6 hook wrappers selinux: remove the SELinux lockdown implementation selinux: enable genfscon labeling for securityfs Smack: Brutalist io_uring support selinux: add support for the io_uring access controls lsm,io_uring: add LSM hooks to io_uring io_uring: convert io_uring to the secure anon inode interface fs: add anon_inode_getfile_secure() similar to anon_inode_getfd_secure() audit: add filtering for io_uring records audit,io_uring,io-wq: add some basic audit support to io_uring audit: prepare audit_context for use in calling contexts beyond syscalls
| * security: Return xattr name from security_dentry_init_security()Vivek Goyal2021-10-201-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Right now security_dentry_init_security() only supports single security label and is used by SELinux only. There are two users of this hook, namely ceph and nfs. NFS does not care about xattr name. Ceph hardcodes the xattr name to security.selinux (XATTR_NAME_SELINUX). I am making changes to fuse/virtiofs to send security label to virtiofsd and I need to send xattr name as well. I also hardcoded the name of xattr to security.selinux. Stephen Smalley suggested that it probably is a good idea to modify security_dentry_init_security() to also return name of xattr so that we can avoid this hardcoding in the callers. This patch adds a new parameter "const char **xattr_name" to security_dentry_init_security() and LSM puts the name of xattr too if caller asked for it (xattr_name != NULL). Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: James Morris <jamorris@linux.microsoft.com> [PM: fixed typos in the commit description] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: fix a sock regression in selinux_ip_postroute_compat()Paul Moore2021-10-191-2/+2
| | | | | | | | | | | | | | | | | | | | Unfortunately we can't rely on nf_hook_state->sk being the proper originating socket so revert to using skb_to_full_sk(skb). Fixes: 1d1e1ded1356 ("selinux: make better use of the nf_hook_state passed to the NF hooks") Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * binder: use cred instead of task for selinux checksTodd Kjos2021-10-141-35/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since binder was integrated with selinux, it has passed 'struct task_struct' associated with the binder_proc to represent the source and target of transactions. The conversion of task to SID was then done in the hook implementations. It turns out that there are race conditions which can result in an incorrect security context being used. Fix by using the 'struct cred' saved during binder_open and pass it to the selinux subsystem. Cc: stable@vger.kernel.org # 5.14 (need backport for earlier stables) Fixes: 79af73079d75 ("Add security hooks to binder and implement the hooks for SELinux.") Suggested-by: Jann Horn <jannh@google.com> Signed-off-by: Todd Kjos <tkjos@google.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: fix all of the W=1 build warningsPaul Moore2021-10-136-8/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | There were a number of places in the code where the function definition did not match the associated comment block as well at least one file where the appropriate header files were not included (missing function declaration/prototype); this patch fixes all of these issue such that building the SELinux code with "W=1" is now warning free. % make W=1 security/selinux/ Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: make better use of the nf_hook_state passed to the NF hooksPaul Moore2021-10-131-27/+25
| | | | | | | | | | | | | | | | | | This patch builds on a previous SELinux/netfilter patch by Florian Westphal and makes better use of the nf_hook_state variable passed into the SELinux/netfilter hooks as well as a number of other small cleanups in the related code. Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: fix race condition when computing ocontext SIDsOndrej Mosnacek2021-10-111-85/+77
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current code contains a lot of racy patterns when converting an ocontext's context structure to an SID. This is being done in a "lazy" fashion, such that the SID is looked up in the SID table only when it's first needed and then cached in the "sid" field of the ocontext structure. However, this is done without any locking or memory barriers and is thus unsafe. Between commits 24ed7fdae669 ("selinux: use separate table for initial SID lookup") and 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table"), this race condition lead to an actual observable bug, because a pointer to the shared sid field was passed directly to sidtab_context_to_sid(), which was using this location to also store an intermediate value, which could have been read by other threads and interpreted as an SID. In practice this caused e.g. new mounts to get a wrong (seemingly random) filesystem context, leading to strange denials. This bug has been spotted in the wild at least twice, see [1] and [2]. Fix the race condition by making all the racy functions use a common helper that ensures the ocontext::sid accesses are made safely using the appropriate SMP constructs. Note that security_netif_sid() was populating the sid field of both contexts stored in the ocontext, but only the first one was actually used. The SELinux wiki's documentation on the "netifcon" policy statement [3] suggests that using only the first context is intentional. I kept only the handling of the first context here, as there is really no point in doing the SID lookup for the unused one. I wasn't able to reproduce the bug mentioned above on any kernel that includes commit 66f8e2f03c02, even though it has been reported that the issue occurs with that commit, too, just less frequently. Thus, I wasn't able to verify that this patch fixes the issue, but it makes sense to avoid the race condition regardless. [1] https://github.com/containers/container-selinux/issues/89 [2] https://lists.fedoraproject.org/archives/list/selinux@lists.fedoraproject.org/thread/6DMTAMHIOAOEMUAVTULJD45JZU7IBAFM/ [3] https://selinuxproject.org/page/NetworkStatements#netifcon Cc: stable@vger.kernel.org Cc: Xinjie Zheng <xinjie@google.com> Reported-by: Sujithra Periasamy <sujithra@google.com> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: remove unneeded ipv6 hook wrappersFlorian Westphal2021-10-111-62/+18
| | | | | | | | | | | | | | | | | | | | | | | | Netfilter places the protocol number the hook function is getting called from in state->pf, so we can use that instead of an extra wrapper. While at it, remove one-line wrappers too and make selinux_ip_{out,forward,postroute} useable as hook function. Signed-off-by: Florian Westphal <fw@strlen.de> Message-Id: <20211011202229.28289-1-fw@strlen.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: remove the SELinux lockdown implementationPaul Moore2021-09-302-32/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NOTE: This patch intentionally omits any "Fixes:" metadata or stable tagging since it removes a SELinux access control check; while removing the control point is the right thing to do moving forward, removing it in stable kernels could be seen as a regression. The original SELinux lockdown implementation in 59438b46471a ("security,lockdown,selinux: implement SELinux lockdown") used the current task's credentials as both the subject and object in the SELinux lockdown hook, selinux_lockdown(). Unfortunately that proved to be incorrect in a number of cases as the core kernel was calling the LSM lockdown hook in places where the credentials from the "current" task_struct were not the correct credentials to use in the SELinux access check. Attempts were made to resolve this by adding a credential pointer to the LSM lockdown hook as well as suggesting that the single hook be split into two: one for user tasks, one for kernel tasks; however neither approach was deemed acceptable by Linus. Faced with the prospect of either changing the subj/obj in the access check to a constant context (likely the kernel's label) or removing the SELinux lockdown check entirely, the SELinux community decided that removing the lockdown check was preferable. The supporting changes to the general LSM layer are left intact, this patch only removes the SELinux implementation. Acked-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: enable genfscon labeling for securityfsChristian Göttsche2021-09-281-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for genfscon per-file labeling of securityfs files. This allows for separate labels and thereby access control for different files. For example a genfscon statement genfscon securityfs /integrity/ima/policy \ system_u:object_r:ima_policy_t:s0 will set a private label to the IMA policy file and thus allow to control the ability to set the IMA policy. Setting labels directly with setxattr(2), e.g. by chcon(1) or setfiles(8), is still not supported. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> [PM: line width fixes in the commit description] Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: add support for the io_uring access controlsPaul Moore2021-09-192-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements two new io_uring access controls, specifically support for controlling the io_uring "personalities" and IORING_SETUP_SQPOLL. Controlling the sharing of io_urings themselves is handled via the normal file/inode labeling and sharing mechanisms. The io_uring { override_creds } permission restricts which domains the subject domain can use to override it's own credentials. Granting a domain the io_uring { override_creds } permission allows it to impersonate another domain in io_uring operations. The io_uring { sqpoll } permission restricts which domains can create asynchronous io_uring polling threads. This is important from a security perspective as operations queued by this asynchronous thread inherit the credentials of the thread creator by default; if an io_uring is shared across process/domain boundaries this could result in one domain impersonating another. Controlling the creation of sqpoll threads, and the sharing of io_urings across processes, allow policy authors to restrict the ability of one domain to impersonate another via io_uring. As a quick summary, this patch adds a new object class with two permissions: io_uring { override_creds sqpoll } These permissions can be seen in the two simple policy statements below: allow domA_t domB_t : io_uring { override_creds }; allow domA_t self : io_uring { sqpoll }; Signed-off-by: Paul Moore <paul@paul-moore.com>
* | Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/David S. Miller2021-10-071-1/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2021-10-07 1) Fix a sysbot reported shift-out-of-bounds in xfrm_get_default. From Pavel Skripkin. 2) Fix XFRM_MSG_MAPPING ABI breakage. The new XFRM_MSG_MAPPING messages were accidentally not paced at the end. Fix by Eugene Syromiatnikov. 3) Fix the uapi for the default policy, use explicit field and macros and make it accessible to userland. From Nicolas Dichtel. 4) Fix a missing rcu lock in xfrm_notify_userpolicy(). From Nicolas Dichtel. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * | include/uapi/linux/xfrm.h: Fix XFRM_MSG_MAPPING ABI breakageEugene Syromiatnikov2021-09-141-1/+3
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 2d151d39073a ("xfrm: Add possibility to set the default to block if we have no policy") broke ABI by changing the value of the XFRM_MSG_MAPPING enum item, thus also evading the build-time check in security/selinux/nlmsgtab.c:selinux_nlmsg_lookup for presence of proper security permission checks in nlmsg_xfrm_perms. Fix it by placing XFRM_MSG_SETDEFAULT/XFRM_MSG_GETDEFAULT to the end of the enum, right before __XFRM_MSG_MAX, and updating the nlmsg_xfrm_perms accordingly. Fixes: 2d151d39073a ("xfrm: Add possibility to set the default to block if we have no policy") References: https://lore.kernel.org/netdev/20210901151402.GA2557@altlinux.org/ Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Acked-by: Antony Antony <antony.antony@secunet.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
* / selinux,smack: fix subjective/objective credential use mixupsPaul Moore2021-09-231-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | Jann Horn reported a problem with commit eb1231f73c4d ("selinux: clarify task subjective and objective credentials") where some LSM hooks were attempting to access the subjective credentials of a task other than the current task. Generally speaking, it is not safe to access another task's subjective credentials and doing so can cause a number of problems. Further, while looking into the problem, I realized that Smack was suffering from a similar problem brought about by a similar commit 1fb057dcde11 ("smack: differentiate between subjective and objective task credentials"). This patch addresses this problem by restoring the use of the task's objective credentials in those cases where the task is other than the current executing task. Not only does this resolve the problem reported by Jann, it is arguably the correct thing to do in these cases. Cc: stable@vger.kernel.org Fixes: eb1231f73c4d ("selinux: clarify task subjective and objective credentials") Fixes: 1fb057dcde11 ("smack: differentiate between subjective and objective task credentials") Reported-by: Jann Horn <jannh@google.com> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Paul Moore <paul@paul-moore.com>