Revision 9c1c2b35f1d94de8325344c2777d7ee67492db3b authored by Jeff Layton on 03 April 2019, 17:16:01 UTC, committed by Ilya Dryomov on 21 January 2020, 18:02:37 UTC
Currently, we just assume that it will stick around by virtue of the
submitter's reference, but later patches will allow the syscall to
return early and we can't rely on that reference at that point.

While I'm not aware of any reports of it, Xiubo pointed out that this
may fix a use-after-free.  If the wait for a reply times out or is
canceled via signal, and then the reply comes in after the syscall
returns, the client can end up trying to access r_parent without a
reference.

Take an extra reference to the inode when setting r_parent and release
it when releasing the request.

Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
1 parent def9d27
Raw File
rmd160.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Cryptographic API.
 *
 * RIPEMD-160 - RACE Integrity Primitives Evaluation Message Digest.
 *
 * Based on the reference implementation by Antoon Bosselaers, ESAT-COSIC
 *
 * Copyright (c) 2008 Adrian-Ken Rueegsegger <ken@codelabs.ch>
 */
#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <asm/byteorder.h>

#include "ripemd.h"

struct rmd160_ctx {
	u64 byte_count;
	u32 state[5];
	__le32 buffer[16];
};

#define K1  RMD_K1
#define K2  RMD_K2
#define K3  RMD_K3
#define K4  RMD_K4
#define K5  RMD_K5
#define KK1 RMD_K6
#define KK2 RMD_K7
#define KK3 RMD_K8
#define KK4 RMD_K9
#define KK5 RMD_K1

#define F1(x, y, z) (x ^ y ^ z)		/* XOR */
#define F2(x, y, z) (z ^ (x & (y ^ z)))	/* x ? y : z */
#define F3(x, y, z) ((x | ~y) ^ z)
#define F4(x, y, z) (y ^ (z & (x ^ y)))	/* z ? x : y */
#define F5(x, y, z) (x ^ (y | ~z))

#define ROUND(a, b, c, d, e, f, k, x, s)  { \
	(a) += f((b), (c), (d)) + le32_to_cpup(&(x)) + (k); \
	(a) = rol32((a), (s)) + (e); \
	(c) = rol32((c), 10); \
}

static void rmd160_transform(u32 *state, const __le32 *in)
{
	u32 aa, bb, cc, dd, ee, aaa, bbb, ccc, ddd, eee;

	/* Initialize left lane */
	aa = state[0];
	bb = state[1];
	cc = state[2];
	dd = state[3];
	ee = state[4];

	/* Initialize right lane */
	aaa = state[0];
	bbb = state[1];
	ccc = state[2];
	ddd = state[3];
	eee = state[4];

	/* round 1: left lane */
	ROUND(aa, bb, cc, dd, ee, F1, K1, in[0],  11);
	ROUND(ee, aa, bb, cc, dd, F1, K1, in[1],  14);
	ROUND(dd, ee, aa, bb, cc, F1, K1, in[2],  15);
	ROUND(cc, dd, ee, aa, bb, F1, K1, in[3],  12);
	ROUND(bb, cc, dd, ee, aa, F1, K1, in[4],   5);
	ROUND(aa, bb, cc, dd, ee, F1, K1, in[5],   8);
	ROUND(ee, aa, bb, cc, dd, F1, K1, in[6],   7);
	ROUND(dd, ee, aa, bb, cc, F1, K1, in[7],   9);
	ROUND(cc, dd, ee, aa, bb, F1, K1, in[8],  11);
	ROUND(bb, cc, dd, ee, aa, F1, K1, in[9],  13);
	ROUND(aa, bb, cc, dd, ee, F1, K1, in[10], 14);
	ROUND(ee, aa, bb, cc, dd, F1, K1, in[11], 15);
	ROUND(dd, ee, aa, bb, cc, F1, K1, in[12],  6);
	ROUND(cc, dd, ee, aa, bb, F1, K1, in[13],  7);
	ROUND(bb, cc, dd, ee, aa, F1, K1, in[14],  9);
	ROUND(aa, bb, cc, dd, ee, F1, K1, in[15],  8);

	/* round 2: left lane" */
	ROUND(ee, aa, bb, cc, dd, F2, K2, in[7],   7);
	ROUND(dd, ee, aa, bb, cc, F2, K2, in[4],   6);
	ROUND(cc, dd, ee, aa, bb, F2, K2, in[13],  8);
	ROUND(bb, cc, dd, ee, aa, F2, K2, in[1],  13);
	ROUND(aa, bb, cc, dd, ee, F2, K2, in[10], 11);
	ROUND(ee, aa, bb, cc, dd, F2, K2, in[6],   9);
	ROUND(dd, ee, aa, bb, cc, F2, K2, in[15],  7);
	ROUND(cc, dd, ee, aa, bb, F2, K2, in[3],  15);
	ROUND(bb, cc, dd, ee, aa, F2, K2, in[12],  7);
	ROUND(aa, bb, cc, dd, ee, F2, K2, in[0],  12);
	ROUND(ee, aa, bb, cc, dd, F2, K2, in[9],  15);
	ROUND(dd, ee, aa, bb, cc, F2, K2, in[5],   9);
	ROUND(cc, dd, ee, aa, bb, F2, K2, in[2],  11);
	ROUND(bb, cc, dd, ee, aa, F2, K2, in[14],  7);
	ROUND(aa, bb, cc, dd, ee, F2, K2, in[11], 13);
	ROUND(ee, aa, bb, cc, dd, F2, K2, in[8],  12);

	/* round 3: left lane" */
	ROUND(dd, ee, aa, bb, cc, F3, K3, in[3],  11);
	ROUND(cc, dd, ee, aa, bb, F3, K3, in[10], 13);
	ROUND(bb, cc, dd, ee, aa, F3, K3, in[14],  6);
	ROUND(aa, bb, cc, dd, ee, F3, K3, in[4],   7);
	ROUND(ee, aa, bb, cc, dd, F3, K3, in[9],  14);
	ROUND(dd, ee, aa, bb, cc, F3, K3, in[15],  9);
	ROUND(cc, dd, ee, aa, bb, F3, K3, in[8],  13);
	ROUND(bb, cc, dd, ee, aa, F3, K3, in[1],  15);
	ROUND(aa, bb, cc, dd, ee, F3, K3, in[2],  14);
	ROUND(ee, aa, bb, cc, dd, F3, K3, in[7],   8);
	ROUND(dd, ee, aa, bb, cc, F3, K3, in[0],  13);
	ROUND(cc, dd, ee, aa, bb, F3, K3, in[6],   6);
	ROUND(bb, cc, dd, ee, aa, F3, K3, in[13],  5);
	ROUND(aa, bb, cc, dd, ee, F3, K3, in[11], 12);
	ROUND(ee, aa, bb, cc, dd, F3, K3, in[5],   7);
	ROUND(dd, ee, aa, bb, cc, F3, K3, in[12],  5);

	/* round 4: left lane" */
	ROUND(cc, dd, ee, aa, bb, F4, K4, in[1],  11);
	ROUND(bb, cc, dd, ee, aa, F4, K4, in[9],  12);
	ROUND(aa, bb, cc, dd, ee, F4, K4, in[11], 14);
	ROUND(ee, aa, bb, cc, dd, F4, K4, in[10], 15);
	ROUND(dd, ee, aa, bb, cc, F4, K4, in[0],  14);
	ROUND(cc, dd, ee, aa, bb, F4, K4, in[8],  15);
	ROUND(bb, cc, dd, ee, aa, F4, K4, in[12],  9);
	ROUND(aa, bb, cc, dd, ee, F4, K4, in[4],   8);
	ROUND(ee, aa, bb, cc, dd, F4, K4, in[13],  9);
	ROUND(dd, ee, aa, bb, cc, F4, K4, in[3],  14);
	ROUND(cc, dd, ee, aa, bb, F4, K4, in[7],   5);
	ROUND(bb, cc, dd, ee, aa, F4, K4, in[15],  6);
	ROUND(aa, bb, cc, dd, ee, F4, K4, in[14],  8);
	ROUND(ee, aa, bb, cc, dd, F4, K4, in[5],   6);
	ROUND(dd, ee, aa, bb, cc, F4, K4, in[6],   5);
	ROUND(cc, dd, ee, aa, bb, F4, K4, in[2],  12);

	/* round 5: left lane" */
	ROUND(bb, cc, dd, ee, aa, F5, K5, in[4],   9);
	ROUND(aa, bb, cc, dd, ee, F5, K5, in[0],  15);
	ROUND(ee, aa, bb, cc, dd, F5, K5, in[5],   5);
	ROUND(dd, ee, aa, bb, cc, F5, K5, in[9],  11);
	ROUND(cc, dd, ee, aa, bb, F5, K5, in[7],   6);
	ROUND(bb, cc, dd, ee, aa, F5, K5, in[12],  8);
	ROUND(aa, bb, cc, dd, ee, F5, K5, in[2],  13);
	ROUND(ee, aa, bb, cc, dd, F5, K5, in[10], 12);
	ROUND(dd, ee, aa, bb, cc, F5, K5, in[14],  5);
	ROUND(cc, dd, ee, aa, bb, F5, K5, in[1],  12);
	ROUND(bb, cc, dd, ee, aa, F5, K5, in[3],  13);
	ROUND(aa, bb, cc, dd, ee, F5, K5, in[8],  14);
	ROUND(ee, aa, bb, cc, dd, F5, K5, in[11], 11);
	ROUND(dd, ee, aa, bb, cc, F5, K5, in[6],   8);
	ROUND(cc, dd, ee, aa, bb, F5, K5, in[15],  5);
	ROUND(bb, cc, dd, ee, aa, F5, K5, in[13],  6);

	/* round 1: right lane */
	ROUND(aaa, bbb, ccc, ddd, eee, F5, KK1, in[5],   8);
	ROUND(eee, aaa, bbb, ccc, ddd, F5, KK1, in[14],  9);
	ROUND(ddd, eee, aaa, bbb, ccc, F5, KK1, in[7],   9);
	ROUND(ccc, ddd, eee, aaa, bbb, F5, KK1, in[0],  11);
	ROUND(bbb, ccc, ddd, eee, aaa, F5, KK1, in[9],  13);
	ROUND(aaa, bbb, ccc, ddd, eee, F5, KK1, in[2],  15);
	ROUND(eee, aaa, bbb, ccc, ddd, F5, KK1, in[11], 15);
	ROUND(ddd, eee, aaa, bbb, ccc, F5, KK1, in[4],   5);
	ROUND(ccc, ddd, eee, aaa, bbb, F5, KK1, in[13],  7);
	ROUND(bbb, ccc, ddd, eee, aaa, F5, KK1, in[6],   7);
	ROUND(aaa, bbb, ccc, ddd, eee, F5, KK1, in[15],  8);
	ROUND(eee, aaa, bbb, ccc, ddd, F5, KK1, in[8],  11);
	ROUND(ddd, eee, aaa, bbb, ccc, F5, KK1, in[1],  14);
	ROUND(ccc, ddd, eee, aaa, bbb, F5, KK1, in[10], 14);
	ROUND(bbb, ccc, ddd, eee, aaa, F5, KK1, in[3],  12);
	ROUND(aaa, bbb, ccc, ddd, eee, F5, KK1, in[12],  6);

	/* round 2: right lane */
	ROUND(eee, aaa, bbb, ccc, ddd, F4, KK2, in[6],   9);
	ROUND(ddd, eee, aaa, bbb, ccc, F4, KK2, in[11], 13);
	ROUND(ccc, ddd, eee, aaa, bbb, F4, KK2, in[3],  15);
	ROUND(bbb, ccc, ddd, eee, aaa, F4, KK2, in[7],   7);
	ROUND(aaa, bbb, ccc, ddd, eee, F4, KK2, in[0],  12);
	ROUND(eee, aaa, bbb, ccc, ddd, F4, KK2, in[13],  8);
	ROUND(ddd, eee, aaa, bbb, ccc, F4, KK2, in[5],   9);
	ROUND(ccc, ddd, eee, aaa, bbb, F4, KK2, in[10], 11);
	ROUND(bbb, ccc, ddd, eee, aaa, F4, KK2, in[14],  7);
	ROUND(aaa, bbb, ccc, ddd, eee, F4, KK2, in[15],  7);
	ROUND(eee, aaa, bbb, ccc, ddd, F4, KK2, in[8],  12);
	ROUND(ddd, eee, aaa, bbb, ccc, F4, KK2, in[12],  7);
	ROUND(ccc, ddd, eee, aaa, bbb, F4, KK2, in[4],   6);
	ROUND(bbb, ccc, ddd, eee, aaa, F4, KK2, in[9],  15);
	ROUND(aaa, bbb, ccc, ddd, eee, F4, KK2, in[1],  13);
	ROUND(eee, aaa, bbb, ccc, ddd, F4, KK2, in[2],  11);

	/* round 3: right lane */
	ROUND(ddd, eee, aaa, bbb, ccc, F3, KK3, in[15],  9);
	ROUND(ccc, ddd, eee, aaa, bbb, F3, KK3, in[5],   7);
	ROUND(bbb, ccc, ddd, eee, aaa, F3, KK3, in[1],  15);
	ROUND(aaa, bbb, ccc, ddd, eee, F3, KK3, in[3],  11);
	ROUND(eee, aaa, bbb, ccc, ddd, F3, KK3, in[7],   8);
	ROUND(ddd, eee, aaa, bbb, ccc, F3, KK3, in[14],  6);
	ROUND(ccc, ddd, eee, aaa, bbb, F3, KK3, in[6],   6);
	ROUND(bbb, ccc, ddd, eee, aaa, F3, KK3, in[9],  14);
	ROUND(aaa, bbb, ccc, ddd, eee, F3, KK3, in[11], 12);
	ROUND(eee, aaa, bbb, ccc, ddd, F3, KK3, in[8],  13);
	ROUND(ddd, eee, aaa, bbb, ccc, F3, KK3, in[12],  5);
	ROUND(ccc, ddd, eee, aaa, bbb, F3, KK3, in[2],  14);
	ROUND(bbb, ccc, ddd, eee, aaa, F3, KK3, in[10], 13);
	ROUND(aaa, bbb, ccc, ddd, eee, F3, KK3, in[0],  13);
	ROUND(eee, aaa, bbb, ccc, ddd, F3, KK3, in[4],   7);
	ROUND(ddd, eee, aaa, bbb, ccc, F3, KK3, in[13],  5);

	/* round 4: right lane */
	ROUND(ccc, ddd, eee, aaa, bbb, F2, KK4, in[8],  15);
	ROUND(bbb, ccc, ddd, eee, aaa, F2, KK4, in[6],   5);
	ROUND(aaa, bbb, ccc, ddd, eee, F2, KK4, in[4],   8);
	ROUND(eee, aaa, bbb, ccc, ddd, F2, KK4, in[1],  11);
	ROUND(ddd, eee, aaa, bbb, ccc, F2, KK4, in[3],  14);
	ROUND(ccc, ddd, eee, aaa, bbb, F2, KK4, in[11], 14);
	ROUND(bbb, ccc, ddd, eee, aaa, F2, KK4, in[15],  6);
	ROUND(aaa, bbb, ccc, ddd, eee, F2, KK4, in[0],  14);
	ROUND(eee, aaa, bbb, ccc, ddd, F2, KK4, in[5],   6);
	ROUND(ddd, eee, aaa, bbb, ccc, F2, KK4, in[12],  9);
	ROUND(ccc, ddd, eee, aaa, bbb, F2, KK4, in[2],  12);
	ROUND(bbb, ccc, ddd, eee, aaa, F2, KK4, in[13],  9);
	ROUND(aaa, bbb, ccc, ddd, eee, F2, KK4, in[9],  12);
	ROUND(eee, aaa, bbb, ccc, ddd, F2, KK4, in[7],   5);
	ROUND(ddd, eee, aaa, bbb, ccc, F2, KK4, in[10], 15);
	ROUND(ccc, ddd, eee, aaa, bbb, F2, KK4, in[14],  8);

	/* round 5: right lane */
	ROUND(bbb, ccc, ddd, eee, aaa, F1, KK5, in[12],  8);
	ROUND(aaa, bbb, ccc, ddd, eee, F1, KK5, in[15],  5);
	ROUND(eee, aaa, bbb, ccc, ddd, F1, KK5, in[10], 12);
	ROUND(ddd, eee, aaa, bbb, ccc, F1, KK5, in[4],   9);
	ROUND(ccc, ddd, eee, aaa, bbb, F1, KK5, in[1],  12);
	ROUND(bbb, ccc, ddd, eee, aaa, F1, KK5, in[5],   5);
	ROUND(aaa, bbb, ccc, ddd, eee, F1, KK5, in[8],  14);
	ROUND(eee, aaa, bbb, ccc, ddd, F1, KK5, in[7],   6);
	ROUND(ddd, eee, aaa, bbb, ccc, F1, KK5, in[6],   8);
	ROUND(ccc, ddd, eee, aaa, bbb, F1, KK5, in[2],  13);
	ROUND(bbb, ccc, ddd, eee, aaa, F1, KK5, in[13],  6);
	ROUND(aaa, bbb, ccc, ddd, eee, F1, KK5, in[14],  5);
	ROUND(eee, aaa, bbb, ccc, ddd, F1, KK5, in[0],  15);
	ROUND(ddd, eee, aaa, bbb, ccc, F1, KK5, in[3],  13);
	ROUND(ccc, ddd, eee, aaa, bbb, F1, KK5, in[9],  11);
	ROUND(bbb, ccc, ddd, eee, aaa, F1, KK5, in[11], 11);

	/* combine results */
	ddd += cc + state[1];		/* final result for state[0] */
	state[1] = state[2] + dd + eee;
	state[2] = state[3] + ee + aaa;
	state[3] = state[4] + aa + bbb;
	state[4] = state[0] + bb + ccc;
	state[0] = ddd;
}

static int rmd160_init(struct shash_desc *desc)
{
	struct rmd160_ctx *rctx = shash_desc_ctx(desc);

	rctx->byte_count = 0;

	rctx->state[0] = RMD_H0;
	rctx->state[1] = RMD_H1;
	rctx->state[2] = RMD_H2;
	rctx->state[3] = RMD_H3;
	rctx->state[4] = RMD_H4;

	memset(rctx->buffer, 0, sizeof(rctx->buffer));

	return 0;
}

static int rmd160_update(struct shash_desc *desc, const u8 *data,
			 unsigned int len)
{
	struct rmd160_ctx *rctx = shash_desc_ctx(desc);
	const u32 avail = sizeof(rctx->buffer) - (rctx->byte_count & 0x3f);

	rctx->byte_count += len;

	/* Enough space in buffer? If so copy and we're done */
	if (avail > len) {
		memcpy((char *)rctx->buffer + (sizeof(rctx->buffer) - avail),
		       data, len);
		goto out;
	}

	memcpy((char *)rctx->buffer + (sizeof(rctx->buffer) - avail),
	       data, avail);

	rmd160_transform(rctx->state, rctx->buffer);
	data += avail;
	len -= avail;

	while (len >= sizeof(rctx->buffer)) {
		memcpy(rctx->buffer, data, sizeof(rctx->buffer));
		rmd160_transform(rctx->state, rctx->buffer);
		data += sizeof(rctx->buffer);
		len -= sizeof(rctx->buffer);
	}

	memcpy(rctx->buffer, data, len);

out:
	return 0;
}

/* Add padding and return the message digest. */
static int rmd160_final(struct shash_desc *desc, u8 *out)
{
	struct rmd160_ctx *rctx = shash_desc_ctx(desc);
	u32 i, index, padlen;
	__le64 bits;
	__le32 *dst = (__le32 *)out;
	static const u8 padding[64] = { 0x80, };

	bits = cpu_to_le64(rctx->byte_count << 3);

	/* Pad out to 56 mod 64 */
	index = rctx->byte_count & 0x3f;
	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
	rmd160_update(desc, padding, padlen);

	/* Append length */
	rmd160_update(desc, (const u8 *)&bits, sizeof(bits));

	/* Store state in digest */
	for (i = 0; i < 5; i++)
		dst[i] = cpu_to_le32p(&rctx->state[i]);

	/* Wipe context */
	memset(rctx, 0, sizeof(*rctx));

	return 0;
}

static struct shash_alg alg = {
	.digestsize	=	RMD160_DIGEST_SIZE,
	.init		=	rmd160_init,
	.update		=	rmd160_update,
	.final		=	rmd160_final,
	.descsize	=	sizeof(struct rmd160_ctx),
	.base		=	{
		.cra_name	 =	"rmd160",
		.cra_driver_name =	"rmd160-generic",
		.cra_blocksize	 =	RMD160_BLOCK_SIZE,
		.cra_module	 =	THIS_MODULE,
	}
};

static int __init rmd160_mod_init(void)
{
	return crypto_register_shash(&alg);
}

static void __exit rmd160_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}

subsys_initcall(rmd160_mod_init);
module_exit(rmd160_mod_fini);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Adrian-Ken Rueegsegger <ken@codelabs.ch>");
MODULE_DESCRIPTION("RIPEMD-160 Message Digest");
MODULE_ALIAS_CRYPTO("rmd160");
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