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2017-10-31treewide: Fix function prototypes for module_param_call()Kees Cook
Several function prototypes for the set/get functions defined by module_param_call() have a slightly wrong argument types. This fixes those in an effort to clean up the calls when running under type-enforced compiler instrumentation for CFI. This is the result of running the following semantic patch: @match_module_param_call_function@ declarer name module_param_call; identifier _name, _set_func, _get_func; expression _arg, _mode; @@ module_param_call(_name, _set_func, _get_func, _arg, _mode); @fix_set_prototype depends on match_module_param_call_function@ identifier match_module_param_call_function._set_func; identifier _val, _param; type _val_type, _param_type; @@ int _set_func( -_val_type _val +const char * _val , -_param_type _param +const struct kernel_param * _param ) { ... } @fix_get_prototype depends on match_module_param_call_function@ identifier match_module_param_call_function._get_func; identifier _val, _param; type _val_type, _param_type; @@ int _get_func( -_val_type _val +char * _val , -_param_type _param +const struct kernel_param * _param ) { ... } Two additional by-hand changes are included for places where the above Coccinelle script didn't notice them: drivers/platform/x86/thinkpad_acpi.c fs/lockd/svc.c Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2017-10-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Several conflicts here. NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to nfp_fl_output() needed some adjustments because the code block is in an else block now. Parallel additions to net/pkt_cls.h and net/sch_generic.h A bug fix in __tcp_retransmit_skb() conflicted with some of the rbtree changes in net-next. The tc action RCU callback fixes in 'net' had some overlap with some of the recent tcf_block reworking. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-26Revert "apparmor: add base infastructure for socket mediation"Linus Torvalds
This reverts commit 651e28c5537abb39076d3949fb7618536f1d242e. This caused a regression: "The specific problem is that dnsmasq refuses to start on openSUSE Leap 42.2. The specific cause is that and attempt to open a PF_LOCAL socket gets EACCES. This means that networking doesn't function on a system with a 4.14-rc2 system." Sadly, the developers involved seemed to be in denial for several weeks about this, delaying the revert. This has not been a good release for the security subsystem, and this area needs to change development practices. Reported-and-bisected-by: James Bottomley <James.Bottomley@hansenpartnership.com> Tracked-by: Thorsten Leemhuis <regressions@leemhuis.info> Cc: John Johansen <john.johansen@canonical.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Seth Arnold <seth.arnold@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-24Merge tag 'v4.14-rc6' into locking/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
There were quite a few overlapping sets of changes here. Daniel's bug fix for off-by-ones in the new BPF branch instructions, along with the added allowances for "data_end > ptr + x" forms collided with the metadata additions. Along with those three changes came veritifer test cases, which in their final form I tried to group together properly. If I had just trimmed GIT's conflict tags as-is, this would have split up the meta tests unnecessarily. In the socketmap code, a set of preemption disabling changes overlapped with the rename of bpf_compute_data_end() to bpf_compute_data_pointers(). Changes were made to the mv88e6060.c driver set addr method which got removed in net-next. The hyperv transport socket layer had a locking change in 'net' which overlapped with a change of socket state macro usage in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21tomoyo: fix timestamping for y2038Arnd Bergmann
Tomoyo uses an open-coded version of time_to_tm() to create a timestamp from the current time as read by get_seconds(). This will overflow and give wrong results on 32-bit systems in 2038. To correct this, this changes the code to use ktime_get_real_seconds() and the generic time64_to_tm() function that are both y2038-safe. Using the library function avoids adding an expensive 64-bit division in this code and can benefit from any optimizations we do in common code. Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20selinux: bpf: Add addtional check for bpf object file receiveChenbo Feng
Introduce a bpf object related check when sending and receiving files through unix domain socket as well as binder. It checks if the receiving process have privilege to read/write the bpf map or use the bpf program. This check is necessary because the bpf maps and programs are using a anonymous inode as their shared inode so the normal way of checking the files and sockets when passing between processes cannot work properly on eBPF object. This check only works when the BPF_SYSCALL is configured. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20selinux: bpf: Add selinux check for eBPF syscall operationsChenbo Feng
Implement the actual checks introduced to eBPF related syscalls. This implementation use the security field inside bpf object to store a sid that identify the bpf object. And when processes try to access the object, selinux will check if processes have the right privileges. The creation of eBPF object are also checked at the general bpf check hook and new cmd introduced to eBPF domain can also be checked there. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20security: bpf: Add LSM hooks for bpf object related syscallChenbo Feng
Introduce several LSM hooks for the syscalls that will allow the userspace to access to eBPF object such as eBPF programs and eBPF maps. The security check is aimed to enforce a per object security protection for eBPF object so only processes with the right priviliges can read/write to a specific map or use a specific eBPF program. Besides that, a general security hook is added before the multiplexer of bpf syscall to check the cmd and the attribute used for the command. The actual security module can decide which command need to be checked and how the cmd should be checked. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20capabilities: audit log other surprising conditionsRichard Guy Briggs
The existing condition tested for process effective capabilities set by file attributes but intended to ignore the change if the result was unsurprisingly an effective full set in the case root is special with a setuid root executable file and we are root. Stated again: - When you execute a setuid root application, it is no surprise and expected that it got all capabilities, so we do not want capabilities recorded. if (pE_grew && !(pE_fullset && (eff_root || real_root) && root_priveleged) ) Now make sure we cover other cases: - If something prevented a setuid root app getting all capabilities and it wound up with one capability only, then it is a surprise and should be logged. When it is a setuid root file, we only want capabilities when the process does not get full capabilities.. root_priveleged && setuid_root && !pE_fullset - Similarly if a non-setuid program does pick up capabilities due to file system based capabilities, then we want to know what capabilities were picked up. When it has file system based capabilities we want the capabilities. !is_setuid && (has_fcap && pP_gained) - If it is a non-setuid file and it gets ambient capabilities, we want the capabilities. !is_setuid && pA_gained - These last two are combined into one due to the common first parameter. Related: https://github.com/linux-audit/audit-kernel/issues/16 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: fix logic for effective root or real rootRichard Guy Briggs
Now that the logic is inverted, it is much easier to see that both real root and effective root conditions had to be met to avoid printing the BPRM_FCAPS record with audit syscalls. This meant that any setuid root applications would print a full BPRM_FCAPS record when it wasn't necessary, cluttering the event output, since the SYSCALL and PATH records indicated the presence of the setuid bit and effective root user id. Require only one of effective root or real root to avoid printing the unnecessary record. Ref: commit 3fc689e96c0c ("Add audit_log_bprm_fcaps/AUDIT_BPRM_FCAPS") See: https://github.com/linux-audit/audit-kernel/issues/16 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: invert logic for clarityRichard Guy Briggs
The way the logic was presented, it was awkward to read and verify. Invert the logic using DeMorgan's Law to be more easily able to read and understand. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: remove a layer of conditional logicRichard Guy Briggs
Remove a layer of conditional logic to make the use of conditions easier to read and analyse. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: move audit log decision to functionRichard Guy Briggs
Move the audit log decision logic to its own function to isolate the complexity in one place. Suggested-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: use intuitive names for id changesRichard Guy Briggs
Introduce a number of inlines to make the use of the negation of uid_eq() easier to read and analyse. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: use root_priveleged inline to clarify logicRichard Guy Briggs
Introduce inline root_privileged() to make use of SECURE_NONROOT easier to read. Suggested-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: rename has_cap to has_fcapRichard Guy Briggs
Rename has_cap to has_fcap to clarify it applies to file capabilities since the entire source file is about capabilities. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: intuitive names for cap gain statusRichard Guy Briggs
Introduce macros cap_gained, cap_grew, cap_full to make the use of the negation of is_subset() easier to read and analyse. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-20capabilities: factor out cap_bprm_set_creds privileged rootRichard Guy Briggs
Factor out the case of privileged root from the function cap_bprm_set_creds() to make the latter easier to read and analyse. Suggested-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Okay-ished-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-19commoncap: move assignment of fs_ns to avoid null pointer dereferenceColin Ian King
The pointer fs_ns is assigned from inode->i_ib->s_user_ns before a null pointer check on inode, hence if inode is actually null we will get a null pointer dereference on this assignment. Fix this by only dereferencing inode after the null pointer check on inode. Detected by CoverityScan CID#1455328 ("Dereference before null check") Fixes: 8db6c34f1dbc ("Introduce v3 namespaced file capabilities") Signed-off-by: Colin Ian King <colin.king@canonical.com> Cc: stable@vger.kernel.org Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-19Merge commit 'tags/keys-fixes-20171018' into fixes-v4.14-rc5James Morris
2017-10-18KEYS: load key flags and expiry time atomically in proc_keys_show()Eric Biggers
In proc_keys_show(), the key semaphore is not held, so the key ->flags and ->expiry can be changed concurrently. We therefore should read them atomically just once. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18KEYS: Load key expiry time atomically in keyring_search_iterator()Eric Biggers
Similar to the case for key_validate(), we should load the key ->expiry once atomically in keyring_search_iterator(), since it can be changed concurrently with the flags whenever the key semaphore isn't held. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18KEYS: load key flags and expiry time atomically in key_validate()Eric Biggers
In key_validate(), load the flags and expiry time once atomically, since these can change concurrently if key_validate() is called without the key semaphore held. And we don't want to get inconsistent results if a variable is referenced multiple times. For example, key->expiry was referenced in both 'if (key->expiry)' and in 'if (now.tv_sec >= key->expiry)', making it theoretically possible to see a spurious EKEYEXPIRED while the expiration time was being removed, i.e. set to 0. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-18KEYS: don't let add_key() update an uninstantiated keyDavid Howells
Currently, when passed a key that already exists, add_key() will call the key's ->update() method if such exists. But this is heavily broken in the case where the key is uninstantiated because it doesn't call __key_instantiate_and_link(). Consequently, it doesn't do most of the things that are supposed to happen when the key is instantiated, such as setting the instantiation state, clearing KEY_FLAG_USER_CONSTRUCT and awakening tasks waiting on it, and incrementing key->user->nikeys. It also never takes key_construction_mutex, which means that ->instantiate() can run concurrently with ->update() on the same key. In the case of the "user" and "logon" key types this causes a memory leak, at best. Maybe even worse, the ->update() methods of the "encrypted" and "trusted" key types actually just dereference a NULL pointer when passed an uninstantiated key. Change key_create_or_update() to wait interruptibly for the key to finish construction before continuing. This patch only affects *uninstantiated* keys. For now we still allow a negatively instantiated key to be updated (thereby positively instantiating it), although that's broken too (the next patch fixes it) and I'm not sure that anyone actually uses that functionality either. Here is a simple reproducer for the bug using the "encrypted" key type (requires CONFIG_ENCRYPTED_KEYS=y), though as noted above the bug pertained to more than just the "encrypted" key type: #include <stdlib.h> #include <unistd.h> #include <keyutils.h> int main(void) { int ringid = keyctl_join_session_keyring(NULL); if (fork()) { for (;;) { const char payload[] = "update user:foo 32"; usleep(rand() % 10000); add_key("encrypted", "desc", payload, sizeof(payload), ringid); keyctl_clear(ringid); } } else { for (;;) request_key("encrypted", "desc", "callout_info", ringid); } } It causes: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: encrypted_update+0xb0/0x170 PGD 7a178067 P4D 7a178067 PUD 77269067 PMD 0 PREEMPT SMP CPU: 0 PID: 340 Comm: reproduce Tainted: G D 4.14.0-rc1-00025-g428490e38b2e #796 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff8a467a39a340 task.stack: ffffb15c40770000 RIP: 0010:encrypted_update+0xb0/0x170 RSP: 0018:ffffb15c40773de8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8a467a275b00 RCX: 0000000000000000 RDX: 0000000000000005 RSI: ffff8a467a275b14 RDI: ffffffffb742f303 RBP: ffffb15c40773e20 R08: 0000000000000000 R09: ffff8a467a275b17 R10: 0000000000000020 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8a4677057180 R15: ffff8a467a275b0f FS: 00007f5d7fb08700(0000) GS:ffff8a467f200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 0000000077262005 CR4: 00000000001606f0 Call Trace: key_create_or_update+0x2bc/0x460 SyS_add_key+0x10c/0x1d0 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x7f5d7f211259 RSP: 002b:00007ffed03904c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 000000003b2a7955 RCX: 00007f5d7f211259 RDX: 00000000004009e4 RSI: 00000000004009ff RDI: 0000000000400a04 RBP: 0000000068db8bad R08: 000000003b2a7955 R09: 0000000000000004 R10: 000000000000001a R11: 0000000000000246 R12: 0000000000400868 R13: 00007ffed03905d0 R14: 0000000000000000 R15: 0000000000000000 Code: 77 28 e8 64 34 1f 00 45 31 c0 31 c9 48 8d 55 c8 48 89 df 48 8d 75 d0 e8 ff f9 ff ff 85 c0 41 89 c4 0f 88 84 00 00 00 4c 8b 7d c8 <49> 8b 75 18 4c 89 ff e8 24 f8 ff ff 85 c0 41 89 c4 78 6d 49 8b RIP: encrypted_update+0xb0/0x170 RSP: ffffb15c40773de8 CR2: 0000000000000018 Cc: <stable@vger.kernel.org> # v2.6.12+ Reported-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Eric Biggers <ebiggers@google.com>
2017-10-18KEYS: Fix race between updating and finding a negative keyDavid Howells
Consolidate KEY_FLAG_INSTANTIATED, KEY_FLAG_NEGATIVE and the rejection error into one field such that: (1) The instantiation state can be modified/read atomically. (2) The error can be accessed atomically with the state. (3) The error isn't stored unioned with the payload pointers. This deals with the problem that the state is spread over three different objects (two bits and a separate variable) and reading or updating them atomically isn't practical, given that not only can uninstantiated keys change into instantiated or rejected keys, but rejected keys can also turn into instantiated keys - and someone accessing the key might not be using any locking. The main side effect of this problem is that what was held in the payload may change, depending on the state. For instance, you might observe the key to be in the rejected state. You then read the cached error, but if the key semaphore wasn't locked, the key might've become instantiated between the two reads - and you might now have something in hand that isn't actually an error code. The state is now KEY_IS_UNINSTANTIATED, KEY_IS_POSITIVE or a negative error code if the key is negatively instantiated. The key_is_instantiated() function is replaced with key_is_positive() to avoid confusion as negative keys are also 'instantiated'. Additionally, barriering is included: (1) Order payload-set before state-set during instantiation. (2) Order state-read before payload-read when using the key. Further separate barriering is necessary if RCU is being used to access the payload content after reading the payload pointers. Fixes: 146aa8b1453b ("KEYS: Merge the type-specific data with the payload data") Cc: stable@vger.kernel.org # v4.4+ Reported-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Eric Biggers <ebiggers@google.com>
2017-10-18security/keys: BIG_KEY requires CONFIG_CRYPTOArnd Bergmann
The recent rework introduced a possible randconfig build failure when CONFIG_CRYPTO configured to only allow modules: security/keys/big_key.o: In function `big_key_crypt': big_key.c:(.text+0x29f): undefined reference to `crypto_aead_setkey' security/keys/big_key.o: In function `big_key_init': big_key.c:(.init.text+0x1a): undefined reference to `crypto_alloc_aead' big_key.c:(.init.text+0x45): undefined reference to `crypto_aead_setauthsize' big_key.c:(.init.text+0x77): undefined reference to `crypto_destroy_tfm' crypto/gcm.o: In function `gcm_hash_crypt_remain_continue': gcm.c:(.text+0x167): undefined reference to `crypto_ahash_finup' crypto/gcm.o: In function `crypto_gcm_exit_tfm': gcm.c:(.text+0x847): undefined reference to `crypto_destroy_tfm' When we 'select CRYPTO' like the other users, we always get a configuration that builds. Fixes: 428490e38b2e ("security/keys: rewrite all of big_key crypto") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-16selinux: remove extraneous initialization of slots_used and max_chain_lenColin Ian King
Variables slots_used and max_chain_len are being initialized to zero twice. Remove the second set of initializations in the for loop. Cleans up the clang warnings: Value stored to 'slots_used' is never read Value stored to 'max_chain_len' is never read Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-16selinux: remove redundant assignment to lenColin Ian King
The variable len is being set to zero and this value is never being read since len is being set to a different value just a few lines later. Remove this redundant assignment. Cleans up clang warning: Value stored to 'len' is never read Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-16selinux: remove redundant assignment to strColin Ian King
str is being assigned to an empty string but str is never being read after that, so the assignment is redundant and can be removed. Moving the declaration of str to a more localised block, cleans up clang warning: "Value stored to 'str' is never read" Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-12KEYS: encrypted: fix dereference of NULL user_key_payloadEric Biggers
A key of type "encrypted" references a "master key" which is used to encrypt and decrypt the encrypted key's payload. However, when we accessed the master key's payload, we failed to handle the case where the master key has been revoked, which sets the payload pointer to NULL. Note that request_key() *does* skip revoked keys, but there is still a window where the key can be revoked before we acquire its semaphore. Fix it by checking for a NULL payload, treating it like a key which was already revoked at the time it was requested. This was an issue for master keys of type "user" only. Master keys can also be of type "trusted", but those cannot be revoked. Fixes: 7e70cb497850 ("keys: add new key-type encrypted") Reviewed-by: James Morris <james.l.morris@oracle.com> Cc: <stable@vger.kernel.org> [v2.6.38+] Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: David Safford <safford@us.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-10locking/rwsem, security/apparmor: Replace homebrew use of write_can_lock() ↵Will Deacon
with lockdep The lockdep subsystem provides a robust way to assert that a lock is held, so use that instead of write_can_lock, which can give incorrect results for qrwlocks. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: John Johansen <john.johansen@canonical.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1507055129-12300-1-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-05timer: Remove expires and data arguments from DEFINE_TIMERKees Cook
Drop the arguments from the macro and adjust all callers with the following script: perl -pi -e 's/DEFINE_TIMER\((.*), 0, 0\);/DEFINE_TIMER($1);/g;' \ $(git grep DEFINE_TIMER | cut -d: -f1 | sort -u | grep -v timer.h) Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # for m68k parts Acked-by: Guenter Roeck <linux@roeck-us.net> # for watchdog parts Acked-by: David S. Miller <davem@davemloft.net> # for networking parts Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Kalle Valo <kvalo@codeaurora.org> # for wireless parts Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: linux-mips@linux-mips.org Cc: Petr Mladek <pmladek@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Sebastian Reichel <sre@kernel.org> Cc: Kalle Valo <kvalo@qca.qualcomm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: linux1394-devel@lists.sourceforge.net Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: linux-s390@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com> Cc: Wim Van Sebroeck <wim@iguana.be> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ursula Braun <ubraun@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Harish Patil <harish.patil@cavium.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Michael Reed <mdr@sgi.com> Cc: Manish Chopra <manish.chopra@cavium.com> Cc: Len Brown <len.brown@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-pm@vger.kernel.org Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Mark Gross <mark.gross@intel.com> Cc: linux-watchdog@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Guenter Roeck <linux@roeck-us.net> Cc: netdev@vger.kernel.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linuxppc-dev@lists.ozlabs.org Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Link: https://lkml.kernel.org/r/1507159627-127660-11-git-send-email-keescook@chromium.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-10-04selinux: fix build warningCorentin LABBE
This patch make selinux_task_prlimit() static since it is not used anywhere else. This fix the following build warning: security/selinux/hooks.c:3981:5: warning: no previous prototype for 'selinux_task_prlimit' [-Wmissing-prototypes] Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-04selinux: fix build warning by removing the unused sid variableCorentin LABBE
This patch remove the unused variable sid This fix the following build warning: security/selinux/hooks.c:2921:6: warning: variable 'sid' set but not used [-Wunused-but-set-variable] Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-04selinux: Perform both commoncap and selinux xattr checksEric W. Biederman
When selinux is loaded the relax permission checks for writing security.capable are not honored. Which keeps file capabilities from being used in user namespaces. Stephen Smalley <sds@tycho.nsa.gov> writes: > Originally SELinux called the cap functions directly since there was no > stacking support in the infrastructure and one had to manually stack a > secondary module internally. inode_setxattr and inode_removexattr > however were special cases because the cap functions would check > CAP_SYS_ADMIN for any non-capability attributes in the security.* > namespace, and we don't want to impose that requirement on setting > security.selinux. Thus, we inlined the capabilities logic into the > selinux hook functions and adapted it appropriately. Now that the permission checks in commoncap have evolved this inlining of their contents has become a problem. So restructure selinux_inode_removexattr, and selinux_inode_setxattr to call both the corresponding cap_inode_ function and dentry_has_perm when the attribute is not a selinux security xattr. This ensures the policies of both commoncap and selinux are enforced. This results in smack and selinux having the same basic structure for setxattr and removexattr. Performing their own special permission checks when it is their modules xattr being written to, and deferring to commoncap when that is not the case. Then finally performing their generic module policy on all xattr writes. This structure is fine when you only consider stacking with the commoncap lsm, but it becomes a problem if two lsms that don't want the commoncap security checks on their own attributes need to be stack. This means there will need to be updates in the future as lsm stacking is improved, but at least now the structure between smack and selinux is common making the code easier to refactor. This change also has the effect that selinux_linux_setotherxattr becomes unnecessary so it is removed. Fixes: 8db6c34f1dbc ("Introduce v3 namespaced file capabilities") Fixes: 7bbf0e052b76 ("[PATCH] selinux merge") Historical Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-04lsm: fix smack_inode_removexattr and xattr_getsecurity memleakCasey Schaufler
security_inode_getsecurity() provides the text string value of a security attribute. It does not provide a "secctx". The code in xattr_getsecurity() that calls security_inode_getsecurity() and then calls security_release_secctx() happened to work because SElinux and Smack treat the attribute and the secctx the same way. It fails for cap_inode_getsecurity(), because that module has no secctx that ever needs releasing. It turns out that Smack is the one that's doing things wrong by not allocating memory when instructed to do so by the "alloc" parameter. The fix is simple enough. Change the security_release_secctx() to kfree() because it isn't a secctx being returned by security_inode_getsecurity(). Change Smack to allocate the string when told to do so. Note: this also fixes memory leaks for LSMs which implement inode_getsecurity but not release_secctx, such as capabilities. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: stable@vger.kernel.org Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-09-28Merge commit 'keys-fixes-20170927' into fixes-v4.14-rc3James Morris
From David Howells: "There are two sets of patches here: (1) A bunch of core keyrings bug fixes from Eric Biggers. (2) Fixing big_key to use safe crypto from Jason A. Donenfeld."
2017-09-25security/keys: rewrite all of big_key cryptoJason A. Donenfeld
This started out as just replacing the use of crypto/rng with get_random_bytes_wait, so that we wouldn't use bad randomness at boot time. But, upon looking further, it appears that there were even deeper underlying cryptographic problems, and that this seems to have been committed with very little crypto review. So, I rewrote the whole thing, trying to keep to the conventions introduced by the previous author, to fix these cryptographic flaws. It makes no sense to seed crypto/rng at boot time and then keep using it like this, when in fact there's already get_random_bytes_wait, which can ensure there's enough entropy and be a much more standard way of generating keys. Since this sensitive material is being stored untrusted, using ECB and no authentication is simply not okay at all. I find it surprising and a bit horrifying that this code even made it past basic crypto review, which perhaps points to some larger issues. This patch moves from using AES-ECB to using AES-GCM. Since keys are uniquely generated each time, we can set the nonce to zero. There was also a race condition in which the same key would be reused at the same time in different threads. A mutex fixes this issue now. So, to summarize, this commit fixes the following vulnerabilities: * Low entropy key generation, allowing an attacker to potentially guess or predict keys. * Unauthenticated encryption, allowing an attacker to modify the cipher text in particular ways in order to manipulate the plaintext, which is is even more frightening considering the next point. * Use of ECB mode, allowing an attacker to trivially swap blocks or compare identical plaintext blocks. * Key re-use. * Faulty memory zeroing. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Kirill Marinushkin <k.marinushkin@gmail.com> Cc: security@kernel.org Cc: stable@vger.kernel.org
2017-09-25security/keys: properly zero out sensitive key material in big_keyJason A. Donenfeld
Error paths forgot to zero out sensitive material, so this patch changes some kfrees into a kzfrees. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Eric Biggers <ebiggers3@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Kirill Marinushkin <k.marinushkin@gmail.com> Cc: security@kernel.org Cc: stable@vger.kernel.org
2017-09-25KEYS: use kmemdup() in request_key_auth_new()Eric Biggers
kmemdup() is preferred to kmalloc() followed by memcpy(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: restrict /proc/keys by credentials at open timeEric Biggers
When checking for permission to view keys whilst reading from /proc/keys, we should use the credentials with which the /proc/keys file was opened. This is because, in a classic type of exploit, it can be possible to bypass checks for the *current* credentials by passing the file descriptor to a suid program. Following commit 34dbbcdbf633 ("Make file credentials available to the seqfile interfaces") we can finally fix it. So let's do it. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: reset parent each time before searching key_user_treeEric Biggers
In key_user_lookup(), if there is no key_user for the given uid, we drop key_user_lock, allocate a new key_user, and search the tree again. But we failed to set 'parent' to NULL at the beginning of the second search. If the tree were to be empty for the second search, the insertion would be done with an invalid 'parent', scribbling over freed memory. Fortunately this can't actually happen currently because the tree always contains at least the root_key_user. But it still should be fixed to make the code more robust. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: prevent KEYCTL_READ on negative keyEric Biggers
Because keyctl_read_key() looks up the key with no permissions requested, it may find a negatively instantiated key. If the key is also possessed, we went ahead and called ->read() on the key. But the key payload will actually contain the ->reject_error rather than the normal payload. Thus, the kernel oopses trying to read the user_key_payload from memory address (int)-ENOKEY = 0x00000000ffffff82. Fortunately the payload data is stored inline, so it shouldn't be possible to abuse this as an arbitrary memory read primitive... Reproducer: keyctl new_session keyctl request2 user desc '' @s keyctl read $(keyctl show | awk '/user: desc/ {print $1}') It causes a crash like the following: BUG: unable to handle kernel paging request at 00000000ffffff92 IP: user_read+0x33/0xa0 PGD 36a54067 P4D 36a54067 PUD 0 Oops: 0000 [#1] SMP CPU: 0 PID: 211 Comm: keyctl Not tainted 4.14.0-rc1 #337 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014 task: ffff90aa3b74c3c0 task.stack: ffff9878c0478000 RIP: 0010:user_read+0x33/0xa0 RSP: 0018:ffff9878c047bee8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: ffff90aa3d7da340 RCX: 0000000000000017 RDX: 0000000000000000 RSI: 00000000ffffff82 RDI: ffff90aa3d7da340 RBP: ffff9878c047bf00 R08: 00000024f95da94f R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f58ece69740(0000) GS:ffff90aa3e200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000ffffff92 CR3: 0000000036adc001 CR4: 00000000003606f0 Call Trace: keyctl_read_key+0xac/0xe0 SyS_keyctl+0x99/0x120 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x7f58ec787bb9 RSP: 002b:00007ffc8d401678 EFLAGS: 00000206 ORIG_RAX: 00000000000000fa RAX: ffffffffffffffda RBX: 00007ffc8d402800 RCX: 00007f58ec787bb9 RDX: 0000000000000000 RSI: 00000000174a63ac RDI: 000000000000000b RBP: 0000000000000004 R08: 00007ffc8d402809 R09: 0000000000000020 R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffc8d402800 R13: 00007ffc8d4016e0 R14: 0000000000000000 R15: 0000000000000000 Code: e5 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb e8 a4 b4 ad ff 85 c0 74 09 80 3d b9 4c 96 00 00 74 43 48 8b b3 20 01 00 00 4d 85 ed <0f> b7 5e 10 74 29 4d 85 e4 74 24 4c 39 e3 4c 89 e2 4c 89 ef 48 RIP: user_read+0x33/0xa0 RSP: ffff9878c047bee8 CR2: 00000000ffffff92 Fixes: 61ea0c0ba904 ("KEYS: Skip key state checks when checking for possession") Cc: <stable@vger.kernel.org> [v3.13+] Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: prevent creating a different user's keyringsEric Biggers
It was possible for an unprivileged user to create the user and user session keyrings for another user. For example: sudo -u '#3000' sh -c 'keyctl add keyring _uid.4000 "" @u keyctl add keyring _uid_ses.4000 "" @u sleep 15' & sleep 1 sudo -u '#4000' keyctl describe @u sudo -u '#4000' keyctl describe @us This is problematic because these "fake" keyrings won't have the right permissions. In particular, the user who created them first will own them and will have full access to them via the possessor permissions, which can be used to compromise the security of a user's keys: -4: alswrv-----v------------ 3000 0 keyring: _uid.4000 -5: alswrv-----v------------ 3000 0 keyring: _uid_ses.4000 Fix it by marking user and user session keyrings with a flag KEY_FLAG_UID_KEYRING. Then, when searching for a user or user session keyring by name, skip all keyrings that don't have the flag set. Fixes: 69664cf16af4 ("keys: don't generate user and user session keyrings unless they're accessed") Cc: <stable@vger.kernel.org> [v2.6.26+] Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: fix writing past end of user-supplied buffer in keyring_read()Eric Biggers
Userspace can call keyctl_read() on a keyring to get the list of IDs of keys in the keyring. But if the user-supplied buffer is too small, the kernel would write the full list anyway --- which will corrupt whatever userspace memory happened to be past the end of the buffer. Fix it by only filling the space that is available. Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring") Cc: <stable@vger.kernel.org> [v3.13+] Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: fix key refcount leak in keyctl_read_key()Eric Biggers
In keyctl_read_key(), if key_permission() were to return an error code other than EACCES, we would leak a the reference to the key. This can't actually happen currently because key_permission() can only return an error code other than EACCES if security_key_permission() does, only SELinux and Smack implement that hook, and neither can return an error code other than EACCES. But it should still be fixed, as it is a bug waiting to happen. Fixes: 29db91906340 ("[PATCH] Keys: Add LSM hooks for key management [try #3]") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: fix key refcount leak in keyctl_assume_authority()Eric Biggers
In keyctl_assume_authority(), if keyctl_change_reqkey_auth() were to fail, we would leak the reference to the 'authkey'. Currently this can only happen if prepare_creds() fails to allocate memory. But it still should be fixed, as it is a more severe bug waiting to happen. This patch also moves the read of 'authkey->serial' to before the reference to the authkey is dropped. Doing the read after dropping the reference is very fragile because it assumes we still hold another reference to the key. (Which we do, in current->cred->request_key_auth, but there's no reason not to write it in the "obviously correct" way.) Fixes: d84f4f992cbd ("CRED: Inaugurate COW credentials") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: don't revoke uninstantiated key in request_key_auth_new()Eric Biggers
If key_instantiate_and_link() were to fail (which fortunately isn't possible currently), the call to key_revoke(authkey) would crash with a NULL pointer dereference in request_key_auth_revoke() because the key has not yet been instantiated. Fix this by removing the call to key_revoke(). key_put() is sufficient, as it's not possible for an uninstantiated authkey to have been used for anything yet. Fixes: b5f545c880a2 ("[PATCH] keys: Permit running process to instantiate keys") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-09-25KEYS: fix cred refcount leak in request_key_auth_new()Eric Biggers
In request_key_auth_new(), if key_alloc() or key_instantiate_and_link() were to fail, we would leak a reference to the 'struct cred'. Currently this can only happen if key_alloc() fails to allocate memory. But it still should be fixed, as it is a more severe bug waiting to happen. Fix it by cleaning things up to use a helper function which frees a 'struct request_key_auth' correctly. Fixes: d84f4f992cbd ("CRED: Inaugurate COW credentials") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>