summaryrefslogtreecommitdiffstats
path: root/lib/digsig.c
AgeCommit message (Collapse)AuthorFilesLines
2017-10-12lib/digsig: fix dereference of NULL user_key_payloadEric Biggers1-0/+6
digsig_verify() requests a user key, then accesses its payload. However, a revoked key has a NULL payload, and we failed to check for this. 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. Fixes: 051dbb918c7f ("crypto: digital signature verification support") Reviewed-by: James Morris <james.l.morris@oracle.com> Cc: <stable@vger.kernel.org> [v3.3+] Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-03-02KEYS: Differentiate uses of rcu_dereference_key() and user_key_payload()David Howells1-1/+1
rcu_dereference_key() and user_key_payload() are currently being used in two different, incompatible ways: (1) As a wrapper to rcu_dereference() - when only the RCU read lock used to protect the key. (2) As a wrapper to rcu_dereference_protected() - when the key semaphor is used to protect the key and the may be being modified. Fix this by splitting both of the key wrappers to produce: (1) RCU accessors for keys when caller has the key semaphore locked: dereference_key_locked() user_key_payload_locked() (2) RCU accessors for keys when caller holds the RCU read lock: dereference_key_rcu() user_key_payload_rcu() This should fix following warning in the NFS idmapper =============================== [ INFO: suspicious RCU usage. ] 4.10.0 #1 Tainted: G W ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 1 lock held by mount.nfs/5987: #0: (rcu_read_lock){......}, at: [<d000000002527abc>] nfs_idmap_get_key+0x15c/0x420 [nfsv4] stack backtrace: CPU: 1 PID: 5987 Comm: mount.nfs Tainted: G W 4.10.0 #1 Call Trace: dump_stack+0xe8/0x154 (unreliable) lockdep_rcu_suspicious+0x140/0x190 nfs_idmap_get_key+0x380/0x420 [nfsv4] nfs_map_name_to_uid+0x2a0/0x3b0 [nfsv4] decode_getfattr_attrs+0xfac/0x16b0 [nfsv4] decode_getfattr_generic.constprop.106+0xbc/0x150 [nfsv4] nfs4_xdr_dec_lookup_root+0xac/0xb0 [nfsv4] rpcauth_unwrap_resp+0xe8/0x140 [sunrpc] call_decode+0x29c/0x910 [sunrpc] __rpc_execute+0x140/0x8f0 [sunrpc] rpc_run_task+0x170/0x200 [sunrpc] nfs4_call_sync_sequence+0x68/0xa0 [nfsv4] _nfs4_lookup_root.isra.44+0xd0/0xf0 [nfsv4] nfs4_lookup_root+0xe0/0x350 [nfsv4] nfs4_lookup_root_sec+0x70/0xa0 [nfsv4] nfs4_find_root_sec+0xc4/0x100 [nfsv4] nfs4_proc_get_rootfh+0x5c/0xf0 [nfsv4] nfs4_get_rootfh+0x6c/0x190 [nfsv4] nfs4_server_common_setup+0xc4/0x260 [nfsv4] nfs4_create_server+0x278/0x3c0 [nfsv4] nfs4_remote_mount+0x50/0xb0 [nfsv4] mount_fs+0x74/0x210 vfs_kern_mount+0x78/0x220 nfs_do_root_mount+0xb0/0x140 [nfsv4] nfs4_try_mount+0x60/0x100 [nfsv4] nfs_fs_mount+0x5ec/0xda0 [nfs] mount_fs+0x74/0x210 vfs_kern_mount+0x78/0x220 do_mount+0x254/0xf70 SyS_mount+0x94/0x100 system_call+0x38/0xe0 Reported-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-05-31lib/digsig: digsig_verify_rsa(): return -EINVAL if modulo length is zeroNicolai Stange1-3/+5
Currently, if digsig_verify_rsa() detects that the modulo's length is zero, i.e. mlen == 0, it returns -ENOMEM which doesn't really fit here. Make digsig_verify_rsa() return -EINVAL upon mlen == 0. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: mpi_read_from_buffer(): return error codeNicolai Stange1-4/+8
mpi_read_from_buffer() reads a MPI from a buffer into a newly allocated MPI instance. It expects the buffer's leading two bytes to contain the number of bits, followed by the actual payload. On failure, it returns NULL and updates the in/out argument ret_nread somewhat inconsistently: - If the given buffer is too short to contain the leading two bytes encoding the number of bits or their value is unsupported, then ret_nread will be cleared. - If the allocation of the resulting MPI instance fails, ret_nread is left as is. The only user of mpi_read_from_buffer(), digsig_verify_rsa(), simply checks for a return value of NULL and returns -ENOMEM if that happens. While this is all of cosmetic nature only, there is another error condition which currently isn't detectable by the caller of mpi_read_from_buffer(): if the given buffer is too small to hold the number of bits as encoded in its first two bytes, the return value will be non-NULL and *ret_nread > 0. In preparation of communicating this condition to the caller, let mpi_read_from_buffer() return error values by means of the ERR_PTR() mechanism. Make the sole caller of mpi_read_from_buffer(), digsig_verify_rsa(), check the return value for IS_ERR() rather than == NULL. If IS_ERR() is true, return the associated error value rather than the fixed -ENOMEM. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-21KEYS: Merge the type-specific data with the payload dataDavid Howells1-3/+4
Merge the type-specific data with the payload data into one four-word chunk as it seems pointless to keep them separate. Use user_key_payload() for accessing the payloads of overloaded user-defined keys. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cifs@vger.kernel.org cc: ecryptfs@vger.kernel.org cc: linux-ext4@vger.kernel.org cc: linux-f2fs-devel@lists.sourceforge.net cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: linux-ima-devel@lists.sourceforge.net
2014-06-04lib/digsig.c: kernel-doc warning fixesFabian Frederick1-2/+3
Small typo and @return: -> Returns ... Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Duan Jiong <duanj.fnst@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13lib/digsig.c: use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...))Duan Jiong1-1/+1
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> Cc: James Morris <james.l.morris@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21Merge branch 'next' of ↵Linus Torvalds1-27/+14
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "This is basically a maintenance update for the TPM driver and EVM/IMA" Fix up conflicts in lib/digsig.c and security/integrity/ima/ima_main.c * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (45 commits) tpm/ibmvtpm: build only when IBM pseries is configured ima: digital signature verification using asymmetric keys ima: rename hash calculation functions ima: use new crypto_shash API instead of old crypto_hash ima: add policy support for file system uuid evm: add file system uuid to EVM hmac tpm_tis: check pnp_acpi_device return code char/tpm/tpm_i2c_stm_st33: drop temporary variable for return value char/tpm/tpm_i2c_stm_st33: remove dead assignment in tpm_st33_i2c_probe char/tpm/tpm_i2c_stm_st33: Remove __devexit attribute char/tpm/tpm_i2c_stm_st33: Don't use memcpy for one byte assignment tpm_i2c_stm_st33: removed unused variables/code TPM: Wait for TPM_ACCESS tpmRegValidSts to go high at startup tpm: Fix cancellation of TPM commands (interrupt mode) tpm: Fix cancellation of TPM commands (polling mode) tpm: Store TPM vendor ID TPM: Work around buggy TPMs that block during continue self test tpm_i2c_stm_st33: fix oops when i2c client is unavailable char/tpm: Use struct dev_pm_ops for power management TPM: STMicroelectronics ST33 I2C BUILD STUFF ...
2013-02-01digsig: remove unnecessary memory allocation and copyingDmitry Kasatkin1-27/+14
In existing use case, copying of the decoded data is unnecessary in pkcs_1_v1_5_decode_emsa. It is just enough to get pointer to the message. Removing copying and extra buffer allocation. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-02-01digsig: Fix memory leakage in digsig_verify_rsa()YOSHIFUJI Hideaki1-0/+2
digsig_verify_rsa() does not free kmalloc'ed buffer returned by mpi_get_buffer(). Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Cc: stable@vger.kernel.org Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-09-13digsig: add hash size comparision on signature verificationDmitry Kasatkin1-2/+4
When pkcs_1_v1_5_decode_emsa() returns without error and hash sizes do not match, hash comparision is not done and digsig_verify_rsa() returns no error. This is a bug and this patch fixes it. The bug was introduced in v3.3 by commit b35e286a640f ("lib/digsig: pkcs_1_v1_5_decode_emsa cleanup"). Cc: stable@vger.kernel.org Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-02lib/digsig: checks for NULL return valueDmitry Kasatkin1-2/+6
mpi_read_from_buffer() return value must not be NULL. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02lib/digsig: pkcs_1_v1_5_decode_emsa cleanupDmitry Kasatkin1-25/+10
Removed useless 'is_valid' variable in pkcs_1_v1_5_decode_emsa(), which was inhereted from original code. Client now uses return value to check for an error. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2012-02-02lib/digsig: additional sanity checks against badly formated key payloadDmitry Kasatkin1-2/+7
Added sanity checks for possible wrongly formatted key payload data: - minimum key payload size - zero modulus length - corrected upper key payload boundary. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2011-11-09crypto: digital signature verification supportDmitry Kasatkin1-0/+284
This patch implements RSA digital signature verification using GnuPG library. The format of the signature and the public key is defined by their respective headers. The signature header contains version information, algorithm, and keyid, which was used to generate the signature. The key header contains version and algorythim type. The payload of the signature and the key are multi-precision integers. The signing and key management utilities evm-utils provide functionality to generate signatures and load keys into the kernel keyring. When the key is added to the kernel keyring, the keyid defines the name of the key. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com>