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2019-07-05Merge branch 'linus' of ↵Linus Torvalds1-4/+2
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fixes from Herbert Xu: "This fixes two memory leaks and a list corruption bug" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: user - prevent operating on larval algorithms crypto: cryptd - Fix skcipher instance memory leak lib/mpi: Fix karactx leak in mpi_powm
2019-07-03lib/mpi: Fix karactx leak in mpi_powmHerbert Xu1-4/+2
Sometimes mpi_powm will leak karactx because a memory allocation failure causes a bail-out that skips the freeing of karactx. This patch moves the freeing of karactx to the end of the function like everything else so that it can't be skipped. Reported-by: syzbot+f7baccc38dcc1e094e77@syzkaller.appspotmail.com Fixes: cdec9cb5167a ("crypto: GnuPG based MPI lib - source files...") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 26Thomas Gleixner1-14/+1
Based on 1 normalized pattern(s): gnupg is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version gnupg is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa note this code is heavily based on the gnu mp library actually it s the same code with only minor changes in the way the data is stored this is to support the abstraction of an optional secure memory allocation which may be used to avoid revealing of sensitive data due to paging etc the gnu mp library itself is published under the lgpl however i decided to publish this code under the plain gpl extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 14 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170856.639982569@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-07lib/mpi: remove redundant variable esignColin Ian King1-2/+1
Variable esign is being assigned but is never used hence it is redundant and can be removed. Cleans up clang warning: warning: variable 'esign' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-10lib/mpi: call cond_resched() from mpi_powm() loopEric Biggers1-0/+2
On a non-preemptible kernel, if KEYCTL_DH_COMPUTE is called with the largest permitted inputs (16384 bits), the kernel spends 10+ seconds doing modular exponentiation in mpi_powm() without rescheduling. If all threads do it, it locks up the system. Moreover, it can cause rcu_sched-stall warnings. Notwithstanding the insanity of doing this calculation in kernel mode rather than in userspace, fix it by calling cond_resched() as each bit from the exponent is processed. It's still noninterruptible, but at least it's preemptible now. Do the cond_resched() once per bit rather than once per MPI limb because each limb might still easily take 100+ milliseconds on slow CPUs. Cc: <stable@vger.kernel.org> # v4.12+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-25mpi: Fix NULL ptr dereference in mpi_powm() [ver #3]Andrey Ryabinin1-1/+6
This fixes CVE-2016-8650. If mpi_powm() is given a zero exponent, it wants to immediately return either 1 or 0, depending on the modulus. However, if the result was initalised with zero limb space, no limbs space is allocated and a NULL-pointer exception ensues. Fix this by allocating a minimal amount of limb space for the result when the 0-exponent case when the result is 1 and not touching the limb space when the result is 0. This affects the use of RSA keys and X.509 certificates that carry them. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6 PGD 0 Oops: 0002 [#1] SMP Modules linked in: CPU: 3 PID: 3014 Comm: keyctl Not tainted 4.9.0-rc6-fscache+ #278 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff8804011944c0 task.stack: ffff880401294000 RIP: 0010:[<ffffffff8138ce5d>] [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6 RSP: 0018:ffff880401297ad8 EFLAGS: 00010212 RAX: 0000000000000000 RBX: ffff88040868bec0 RCX: ffff88040868bba0 RDX: ffff88040868b260 RSI: ffff88040868bec0 RDI: ffff88040868bee0 RBP: ffff880401297ba8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000047 R11: ffffffff8183b210 R12: 0000000000000000 R13: ffff8804087c7600 R14: 000000000000001f R15: ffff880401297c50 FS: 00007f7a7918c700(0000) GS:ffff88041fb80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000401250000 CR4: 00000000001406e0 Stack: ffff88040868bec0 0000000000000020 ffff880401297b00 ffffffff81376cd4 0000000000000100 ffff880401297b10 ffffffff81376d12 ffff880401297b30 ffffffff81376f37 0000000000000100 0000000000000000 ffff880401297ba8 Call Trace: [<ffffffff81376cd4>] ? __sg_page_iter_next+0x43/0x66 [<ffffffff81376d12>] ? sg_miter_get_next_page+0x1b/0x5d [<ffffffff81376f37>] ? sg_miter_next+0x17/0xbd [<ffffffff8138ba3a>] ? mpi_read_raw_from_sgl+0xf2/0x146 [<ffffffff8132a95c>] rsa_verify+0x9d/0xee [<ffffffff8132acca>] ? pkcs1pad_sg_set_buf+0x2e/0xbb [<ffffffff8132af40>] pkcs1pad_verify+0xc0/0xe1 [<ffffffff8133cb5e>] public_key_verify_signature+0x1b0/0x228 [<ffffffff8133d974>] x509_check_for_self_signed+0xa1/0xc4 [<ffffffff8133cdde>] x509_cert_parse+0x167/0x1a1 [<ffffffff8133d609>] x509_key_preparse+0x21/0x1a1 [<ffffffff8133c3d7>] asymmetric_key_preparse+0x34/0x61 [<ffffffff812fc9f3>] key_create_or_update+0x145/0x399 [<ffffffff812fe227>] SyS_add_key+0x154/0x19e [<ffffffff81001c2b>] do_syscall_64+0x80/0x191 [<ffffffff816825e4>] entry_SYSCALL64_slow_path+0x25/0x25 Code: 56 41 55 41 54 53 48 81 ec a8 00 00 00 44 8b 71 04 8b 42 04 4c 8b 67 18 45 85 f6 89 45 80 0f 84 b4 06 00 00 85 c0 75 2f 41 ff ce <49> c7 04 24 01 00 00 00 b0 01 75 0b 48 8b 41 18 48 83 38 01 0f RIP [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6 RSP <ffff880401297ad8> CR2: 0000000000000000 ---[ end trace d82015255d4a5d8d ]--- Basically, this is a backport of a libgcrypt patch: http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=patch;h=6e1adb05d290aeeb1c230c763970695f4a538526 Fixes: cdec9cb5167a ("crypto: GnuPG based MPI lib - source files (part 1)") Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> cc: linux-ima-devel@lists.sourceforge.net cc: stable@vger.kernel.org Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-10-08MPILIB: Provide count_leading/trailing_zeros() based on arch functionsDavid Howells1-2/+2
Provide count_leading/trailing_zeros() macros based on extant arch bit scanning functions rather than reimplementing from scratch in MPILIB. Whilst we're at it, turn count_foo_zeros(n, x) into n = count_foo_zeros(x). Also move the definition to asm-generic as other people may be interested in using it. Signed-off-by: David Howells <dhowells@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Cc: Arnd Bergmann <arnd@arndb.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-02-02lib/mpi: return error code on dividing by zeroDmitry Kasatkin1-1/+1
Definitely better to return error code than to divide by zero. 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: GnuPG based MPI lib - source files (part 1)Dmitry Kasatkin1-0/+323
Adds the multi-precision-integer maths library which was originally taken from GnuPG and ported to the kernel by (among others) David Howells. This version is taken from Fedora kernel 2.6.32-71.14.1.el6. The difference is that checkpatch reported errors and warnings have been fixed. This library is used to implemenet RSA digital signature verification used in IMA/EVM integrity protection subsystem. Due to patch size limitation, the patch is divided into 4 parts. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
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