The remaining functions added by commit
a8ea8bdd9df92a0e5db5b43900abb7a288b8a53e did not check for memory
allocation errors. Add the checks and change the API to allow errors
to be returned.
Fixes: a8ea8bdd9df9 ("lib/mpi: Extend the MPI library")
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
---
include/linux/mpi.h | 22 +++++++-------
lib/crypto/mpi/mpi-add.c | 38 ++++++++++++++++--------
lib/crypto/mpi/mpi-bit.c | 25 +++++++++++-----
lib/crypto/mpi/mpi-div.c | 55 +++++++++++++++++++++++++----------
lib/crypto/mpi/mpi-internal.h | 11 +++----
lib/crypto/mpi/mpi-mod.c | 4 +--
lib/crypto/mpi/mpi-mul.c | 29 ++++++++++++++----
lib/crypto/mpi/mpiutil.c | 2 ++
8 files changed, 128 insertions(+), 58 deletions(-)
diff --git a/include/linux/mpi.h b/include/linux/mpi.h
index e081428b91ef..47be46f36435 100644
--- a/include/linux/mpi.h
+++ b/include/linux/mpi.h
@@ -59,7 +59,7 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sg, unsigned nbytes,
int *sign);
/*-- mpi-mod.c --*/
-void mpi_mod(MPI rem, MPI dividend, MPI divisor);
+int mpi_mod(MPI rem, MPI dividend, MPI divisor);
/*-- mpi-pow.c --*/
int mpi_powm(MPI res, MPI base, MPI exp, MPI mod);
@@ -75,22 +75,22 @@ int mpi_sub_ui(MPI w, MPI u, unsigned long vval);
void mpi_normalize(MPI a);
unsigned mpi_get_nbits(MPI a);
int mpi_test_bit(MPI a, unsigned int n);
-void mpi_set_bit(MPI a, unsigned int n);
-void mpi_rshift(MPI x, MPI a, unsigned int n);
+int mpi_set_bit(MPI a, unsigned int n);
+int mpi_rshift(MPI x, MPI a, unsigned int n);
/*-- mpi-add.c --*/
-void mpi_add(MPI w, MPI u, MPI v);
-void mpi_sub(MPI w, MPI u, MPI v);
-void mpi_addm(MPI w, MPI u, MPI v, MPI m);
-void mpi_subm(MPI w, MPI u, MPI v, MPI m);
+int mpi_add(MPI w, MPI u, MPI v);
+int mpi_sub(MPI w, MPI u, MPI v);
+int mpi_addm(MPI w, MPI u, MPI v, MPI m);
+int mpi_subm(MPI w, MPI u, MPI v, MPI m);
/*-- mpi-mul.c --*/
-void mpi_mul(MPI w, MPI u, MPI v);
-void mpi_mulm(MPI w, MPI u, MPI v, MPI m);
+int mpi_mul(MPI w, MPI u, MPI v);
+int mpi_mulm(MPI w, MPI u, MPI v, MPI m);
/*-- mpi-div.c --*/
-void mpi_tdiv_r(MPI rem, MPI num, MPI den);
-void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor);
+int mpi_tdiv_r(MPI rem, MPI num, MPI den);
+int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor);
/* inline functions */
diff --git a/lib/crypto/mpi/mpi-add.c b/lib/crypto/mpi/mpi-add.c
index b47c8c35f5fe..3015140d4860 100644
--- a/lib/crypto/mpi/mpi-add.c
+++ b/lib/crypto/mpi/mpi-add.c
@@ -13,11 +13,12 @@
#include "mpi-internal.h"
-void mpi_add(MPI w, MPI u, MPI v)
+int mpi_add(MPI w, MPI u, MPI v)
{
mpi_ptr_t wp, up, vp;
mpi_size_t usize, vsize, wsize;
int usign, vsign, wsign;
+ int err;
if (u->nlimbs < v->nlimbs) { /* Swap U and V. */
usize = v->nlimbs;
@@ -25,7 +26,9 @@ void mpi_add(MPI w, MPI u, MPI v)
vsize = u->nlimbs;
vsign = u->sign;
wsize = usize + 1;
- RESIZE_IF_NEEDED(w, wsize);
+ err = RESIZE_IF_NEEDED(w, wsize);
+ if (err)
+ return err;
/* These must be after realloc (u or v may be the same as w). */
up = v->d;
vp = u->d;
@@ -35,7 +38,9 @@ void mpi_add(MPI w, MPI u, MPI v)
vsize = v->nlimbs;
vsign = v->sign;
wsize = usize + 1;
- RESIZE_IF_NEEDED(w, wsize);
+ err = RESIZE_IF_NEEDED(w, wsize);
+ if (err)
+ return err;
/* These must be after realloc (u or v may be the same as w). */
up = u->d;
vp = v->d;
@@ -77,28 +82,37 @@ void mpi_add(MPI w, MPI u, MPI v)
w->nlimbs = wsize;
w->sign = wsign;
+ return 0;
}
EXPORT_SYMBOL_GPL(mpi_add);
-void mpi_sub(MPI w, MPI u, MPI v)
+int mpi_sub(MPI w, MPI u, MPI v)
{
- MPI vv = mpi_copy(v);
+ int err;
+ MPI vv;
+
+ vv = mpi_copy(v);
+ if (!vv)
+ return -ENOMEM;
+
vv->sign = !vv->sign;
- mpi_add(w, u, vv);
+ err = mpi_add(w, u, vv);
mpi_free(vv);
+
+ return err;
}
EXPORT_SYMBOL_GPL(mpi_sub);
-void mpi_addm(MPI w, MPI u, MPI v, MPI m)
+int mpi_addm(MPI w, MPI u, MPI v, MPI m)
{
- mpi_add(w, u, v);
- mpi_mod(w, w, m);
+ return mpi_add(w, u, v) ?:
+ mpi_mod(w, w, m);
}
EXPORT_SYMBOL_GPL(mpi_addm);
-void mpi_subm(MPI w, MPI u, MPI v, MPI m)
+int mpi_subm(MPI w, MPI u, MPI v, MPI m)
{
- mpi_sub(w, u, v);
- mpi_mod(w, w, m);
+ return mpi_sub(w, u, v) ?:
+ mpi_mod(w, w, m);
}
EXPORT_SYMBOL_GPL(mpi_subm);
diff --git a/lib/crypto/mpi/mpi-bit.c b/lib/crypto/mpi/mpi-bit.c
index c29b85362664..835a2f0622a0 100644
--- a/lib/crypto/mpi/mpi-bit.c
+++ b/lib/crypto/mpi/mpi-bit.c
@@ -76,9 +76,10 @@ EXPORT_SYMBOL_GPL(mpi_test_bit);
/****************
* Set bit N of A.
*/
-void mpi_set_bit(MPI a, unsigned int n)
+int mpi_set_bit(MPI a, unsigned int n)
{
unsigned int i, limbno, bitno;
+ int err;
limbno = n / BITS_PER_MPI_LIMB;
bitno = n % BITS_PER_MPI_LIMB;
@@ -86,27 +87,31 @@ void mpi_set_bit(MPI a, unsigned int n)
if (limbno >= a->nlimbs) {
for (i = a->nlimbs; i < a->alloced; i++)
a->d[i] = 0;
- mpi_resize(a, limbno+1);
+ err = mpi_resize(a, limbno+1);
+ if (err)
+ return err;
a->nlimbs = limbno+1;
}
a->d[limbno] |= (A_LIMB_1<<bitno);
+ return 0;
}
/*
* Shift A by N bits to the right.
*/
-void mpi_rshift(MPI x, MPI a, unsigned int n)
+int mpi_rshift(MPI x, MPI a, unsigned int n)
{
mpi_size_t xsize;
unsigned int i;
unsigned int nlimbs = (n/BITS_PER_MPI_LIMB);
unsigned int nbits = (n%BITS_PER_MPI_LIMB);
+ int err;
if (x == a) {
/* In-place operation. */
if (nlimbs >= x->nlimbs) {
x->nlimbs = 0;
- return;
+ return 0;
}
if (nlimbs) {
@@ -121,7 +126,9 @@ void mpi_rshift(MPI x, MPI a, unsigned int n)
/* Copy and shift by more or equal bits than in a limb. */
xsize = a->nlimbs;
x->sign = a->sign;
- RESIZE_IF_NEEDED(x, xsize);
+ err = RESIZE_IF_NEEDED(x, xsize);
+ if (err)
+ return err;
x->nlimbs = xsize;
for (i = 0; i < a->nlimbs; i++)
x->d[i] = a->d[i];
@@ -129,7 +136,7 @@ void mpi_rshift(MPI x, MPI a, unsigned int n)
if (nlimbs >= x->nlimbs) {
x->nlimbs = 0;
- return;
+ return 0;
}
for (i = 0; i < x->nlimbs - nlimbs; i++)
@@ -143,7 +150,9 @@ void mpi_rshift(MPI x, MPI a, unsigned int n)
/* Copy and shift by less than bits in a limb. */
xsize = a->nlimbs;
x->sign = a->sign;
- RESIZE_IF_NEEDED(x, xsize);
+ err = RESIZE_IF_NEEDED(x, xsize);
+ if (err)
+ return err;
x->nlimbs = xsize;
if (xsize) {
@@ -159,5 +168,7 @@ void mpi_rshift(MPI x, MPI a, unsigned int n)
}
}
MPN_NORMALIZE(x->d, x->nlimbs);
+
+ return 0;
}
EXPORT_SYMBOL_GPL(mpi_rshift);
diff --git a/lib/crypto/mpi/mpi-div.c b/lib/crypto/mpi/mpi-div.c
index 2ff0ebd74fd7..6e5044e72595 100644
--- a/lib/crypto/mpi/mpi-div.c
+++ b/lib/crypto/mpi/mpi-div.c
@@ -14,12 +14,13 @@
#include "mpi-internal.h"
#include "longlong.h"
-void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den);
+int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den);
-void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
+int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
{
int divisor_sign = divisor->sign;
MPI temp_divisor = NULL;
+ int err;
/* We need the original value of the divisor after the remainder has been
* preliminary calculated. We have to copy it to temporary space if it's
@@ -27,16 +28,22 @@ void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
*/
if (rem == divisor) {
temp_divisor = mpi_copy(divisor);
+ if (!temp_divisor)
+ return -ENOMEM;
divisor = temp_divisor;
}
- mpi_tdiv_r(rem, dividend, divisor);
+ err = mpi_tdiv_r(rem, dividend, divisor);
+ if (err)
+ goto free_temp_divisor;
if (((divisor_sign?1:0) ^ (dividend->sign?1:0)) && rem->nlimbs)
- mpi_add(rem, rem, divisor);
+ err = mpi_add(rem, rem, divisor);
- if (temp_divisor)
- mpi_free(temp_divisor);
+free_temp_divisor:
+ mpi_free(temp_divisor);
+
+ return err;
}
/* If den == quot, den needs temporary storage.
@@ -46,12 +53,12 @@ void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
* i.e no extra storage should be allocated.
*/
-void mpi_tdiv_r(MPI rem, MPI num, MPI den)
+int mpi_tdiv_r(MPI rem, MPI num, MPI den)
{
- mpi_tdiv_qr(NULL, rem, num, den);
+ return mpi_tdiv_qr(NULL, rem, num, den);
}
-void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
+int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
{
mpi_ptr_t np, dp;
mpi_ptr_t qp, rp;
@@ -64,13 +71,16 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
mpi_limb_t q_limb;
mpi_ptr_t marker[5];
int markidx = 0;
+ int err;
/* Ensure space is enough for quotient and remainder.
* We need space for an extra limb in the remainder, because it's
* up-shifted (normalized) below.
*/
rsize = nsize + 1;
- mpi_resize(rem, rsize);
+ err = mpi_resize(rem, rsize);
+ if (err)
+ return err;
qsize = rsize - dsize; /* qsize cannot be bigger than this. */
if (qsize <= 0) {
@@ -86,11 +96,14 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
quot->nlimbs = 0;
quot->sign = 0;
}
- return;
+ return 0;
}
- if (quot)
- mpi_resize(quot, qsize);
+ if (quot) {
+ err = mpi_resize(quot, qsize);
+ if (err)
+ return err;
+ }
/* Read pointers here, when reallocation is finished. */
np = num->d;
@@ -112,10 +125,10 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
rsize = rlimb != 0?1:0;
rem->nlimbs = rsize;
rem->sign = sign_remainder;
- return;
+ return 0;
}
-
+ err = -ENOMEM;
if (quot) {
qp = quot->d;
/* Make sure QP and NP point to different objects. Otherwise the
@@ -123,6 +136,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
*/
if (qp == np) { /* Copy NP object to temporary space. */
np = marker[markidx++] = mpi_alloc_limb_space(nsize);
+ if (!np)
+ goto out_free_marker;
MPN_COPY(np, qp, nsize);
}
} else /* Put quotient at top of remainder. */
@@ -143,6 +158,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
* the original contents of the denominator.
*/
tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
+ if (!tp)
+ goto out_free_marker;
mpihelp_lshift(tp, dp, dsize, normalization_steps);
dp = tp;
@@ -164,6 +181,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
mpi_ptr_t tp;
tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
+ if (!tp)
+ goto out_free_marker;
MPN_COPY(tp, dp, dsize);
dp = tp;
}
@@ -198,8 +217,14 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
rem->nlimbs = rsize;
rem->sign = sign_remainder;
+
+ err = 0;
+
+out_free_marker:
while (markidx) {
markidx--;
mpi_free_limb_space(marker[markidx]);
}
+
+ return err;
}
diff --git a/lib/crypto/mpi/mpi-internal.h b/lib/crypto/mpi/mpi-internal.h
index b6fbb43afbc8..8a4f49e3043c 100644
--- a/lib/crypto/mpi/mpi-internal.h
+++ b/lib/crypto/mpi/mpi-internal.h
@@ -52,11 +52,12 @@
typedef mpi_limb_t *mpi_ptr_t; /* pointer to a limb */
typedef int mpi_size_t; /* (must be a signed type) */
-#define RESIZE_IF_NEEDED(a, b) \
- do { \
- if ((a)->alloced < (b)) \
- mpi_resize((a), (b)); \
- } while (0)
+static inline int RESIZE_IF_NEEDED(MPI a, unsigned b)
+{
+ if (a->alloced < b)
+ return mpi_resize(a, b);
+ return 0;
+}
/* Copy N limbs from S to D. */
#define MPN_COPY(d, s, n) \
diff --git a/lib/crypto/mpi/mpi-mod.c b/lib/crypto/mpi/mpi-mod.c
index 691bbdc52fc6..d5fdaec3d0b6 100644
--- a/lib/crypto/mpi/mpi-mod.c
+++ b/lib/crypto/mpi/mpi-mod.c
@@ -7,7 +7,7 @@
#include "mpi-internal.h"
-void mpi_mod(MPI rem, MPI dividend, MPI divisor)
+int mpi_mod(MPI rem, MPI dividend, MPI divisor)
{
- mpi_fdiv_r(rem, dividend, divisor);
+ return mpi_fdiv_r(rem, dividend, divisor);
}
diff --git a/lib/crypto/mpi/mpi-mul.c b/lib/crypto/mpi/mpi-mul.c
index 7f4eda8560dc..892a246216b9 100644
--- a/lib/crypto/mpi/mpi-mul.c
+++ b/lib/crypto/mpi/mpi-mul.c
@@ -13,7 +13,7 @@
#include "mpi-internal.h"
-void mpi_mul(MPI w, MPI u, MPI v)
+int mpi_mul(MPI w, MPI u, MPI v)
{
mpi_size_t usize, vsize, wsize;
mpi_ptr_t up, vp, wp;
@@ -21,6 +21,7 @@ void mpi_mul(MPI w, MPI u, MPI v)
int usign, vsign, sign_product;
int assign_wp = 0;
mpi_ptr_t tmp_limb = NULL;
+ int err;
if (u->nlimbs < v->nlimbs) {
/* Swap U and V. */
@@ -46,15 +47,21 @@ void mpi_mul(MPI w, MPI u, MPI v)
if (w->alloced < wsize) {
if (wp == up || wp == vp) {
wp = mpi_alloc_limb_space(wsize);
+ if (!wp)
+ return -ENOMEM;
assign_wp = 1;
} else {
- mpi_resize(w, wsize);
+ err = mpi_resize(w, wsize);
+ if (err)
+ return err;
wp = w->d;
}
} else { /* Make U and V not overlap with W. */
if (wp == up) {
/* W and U are identical. Allocate temporary space for U. */
up = tmp_limb = mpi_alloc_limb_space(usize);
+ if (!up)
+ return -ENOMEM;
/* Is V identical too? Keep it identical with U. */
if (wp == vp)
vp = up;
@@ -63,6 +70,8 @@ void mpi_mul(MPI w, MPI u, MPI v)
} else if (wp == vp) {
/* W and V are identical. Allocate temporary space for V. */
vp = tmp_limb = mpi_alloc_limb_space(vsize);
+ if (!vp)
+ return -ENOMEM;
/* Copy to the temporary space. */
MPN_COPY(vp, wp, vsize);
}
@@ -71,7 +80,12 @@ void mpi_mul(MPI w, MPI u, MPI v)
if (!vsize)
wsize = 0;
else {
- mpihelp_mul(wp, up, usize, vp, vsize, &cy);
+ err = mpihelp_mul(wp, up, usize, vp, vsize, &cy);
+ if (err) {
+ if (assign_wp)
+ mpi_free_limb_space(wp);
+ goto free_tmp_limb;
+ }
wsize -= cy ? 0:1;
}
@@ -79,14 +93,17 @@ void mpi_mul(MPI w, MPI u, MPI v)
mpi_assign_limb_space(w, wp, wsize);
w->nlimbs = wsize;
w->sign = sign_product;
+
+free_tmp_limb:
if (tmp_limb)
mpi_free_limb_space(tmp_limb);
+ return err;
}
EXPORT_SYMBOL_GPL(mpi_mul);
-void mpi_mulm(MPI w, MPI u, MPI v, MPI m)
+int mpi_mulm(MPI w, MPI u, MPI v, MPI m)
{
- mpi_mul(w, u, v);
- mpi_tdiv_r(w, w, m);
+ return mpi_mul(w, u, v) ?:
+ mpi_tdiv_r(w, w, m);
}
EXPORT_SYMBOL_GPL(mpi_mulm);
diff --git a/lib/crypto/mpi/mpiutil.c b/lib/crypto/mpi/mpiutil.c
index d57fd8afef64..979ece5a81d2 100644
--- a/lib/crypto/mpi/mpiutil.c
+++ b/lib/crypto/mpi/mpiutil.c
@@ -133,6 +133,8 @@ MPI mpi_copy(MPI a)
if (a) {
b = mpi_alloc(a->nlimbs);
+ if (!b)
+ return NULL;
b->nlimbs = a->nlimbs;
b->sign = a->sign;
b->flags = a->flags;
--
2.39.2
