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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /lib/crypto/mpi/mpi-bit.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'lib/crypto/mpi/mpi-bit.c')
-rw-r--r--lib/crypto/mpi/mpi-bit.c177
1 files changed, 177 insertions, 0 deletions
diff --git a/lib/crypto/mpi/mpi-bit.c b/lib/crypto/mpi/mpi-bit.c
new file mode 100644
index 000000000..b3d0e7ddb
--- /dev/null
+++ b/lib/crypto/mpi/mpi-bit.c
@@ -0,0 +1,177 @@
+/* mpi-bit.c - MPI bit level functions
+ * Copyright (C) 1998, 1999 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * 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
+ */
+
+#include <linux/export.h>
+
+#include "mpi-internal.h"
+#include "longlong.h"
+
+#define A_LIMB_1 ((mpi_limb_t) 1)
+
+/****************
+ * Sometimes we have MSL (most significant limbs) which are 0;
+ * this is for some reasons not good, so this function removes them.
+ */
+void mpi_normalize(MPI a)
+{
+ for (; a->nlimbs && !a->d[a->nlimbs - 1]; a->nlimbs--)
+ ;
+}
+
+/****************
+ * Return the number of bits in A.
+ */
+unsigned mpi_get_nbits(MPI a)
+{
+ unsigned n;
+
+ mpi_normalize(a);
+
+ if (a->nlimbs) {
+ mpi_limb_t alimb = a->d[a->nlimbs - 1];
+ if (alimb)
+ n = count_leading_zeros(alimb);
+ else
+ n = BITS_PER_MPI_LIMB;
+ n = BITS_PER_MPI_LIMB - n + (a->nlimbs - 1) * BITS_PER_MPI_LIMB;
+ } else
+ n = 0;
+ return n;
+}
+EXPORT_SYMBOL_GPL(mpi_get_nbits);
+
+/****************
+ * Test whether bit N is set.
+ */
+int mpi_test_bit(MPI a, unsigned int n)
+{
+ unsigned int limbno, bitno;
+ mpi_limb_t limb;
+
+ limbno = n / BITS_PER_MPI_LIMB;
+ bitno = n % BITS_PER_MPI_LIMB;
+
+ if (limbno >= a->nlimbs)
+ return 0; /* too far left: this is a 0 */
+ limb = a->d[limbno];
+ return (limb & (A_LIMB_1 << bitno)) ? 1 : 0;
+}
+EXPORT_SYMBOL_GPL(mpi_test_bit);
+
+/****************
+ * Set bit N of A.
+ */
+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;
+
+ if (limbno >= a->nlimbs) {
+ for (i = a->nlimbs; i < a->alloced; i++)
+ a->d[i] = 0;
+ err = mpi_resize(a, limbno+1);
+ if (err)
+ return err;
+ a->nlimbs = limbno+1;
+ }
+ a->d[limbno] |= (A_LIMB_1<<bitno);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_set_bit);
+
+/*
+ * Shift A by N bits to the right.
+ */
+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 0;
+ }
+
+ if (nlimbs) {
+ for (i = 0; i < x->nlimbs - nlimbs; i++)
+ x->d[i] = x->d[i+nlimbs];
+ x->d[i] = 0;
+ x->nlimbs -= nlimbs;
+ }
+ if (x->nlimbs && nbits)
+ mpihelp_rshift(x->d, x->d, x->nlimbs, nbits);
+ } else if (nlimbs) {
+ /* Copy and shift by more or equal bits than in a limb. */
+ xsize = a->nlimbs;
+ x->sign = a->sign;
+ 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];
+ x->nlimbs = i;
+
+ if (nlimbs >= x->nlimbs) {
+ x->nlimbs = 0;
+ return 0;
+ }
+
+ for (i = 0; i < x->nlimbs - nlimbs; i++)
+ x->d[i] = x->d[i+nlimbs];
+ x->d[i] = 0;
+ x->nlimbs -= nlimbs;
+
+ if (x->nlimbs && nbits)
+ mpihelp_rshift(x->d, x->d, x->nlimbs, nbits);
+ } else {
+ /* Copy and shift by less than bits in a limb. */
+ xsize = a->nlimbs;
+ x->sign = a->sign;
+ err = RESIZE_IF_NEEDED(x, xsize);
+ if (err)
+ return err;
+ x->nlimbs = xsize;
+
+ if (xsize) {
+ if (nbits)
+ mpihelp_rshift(x->d, a->d, x->nlimbs, nbits);
+ else {
+ /* The rshift helper function is not specified for
+ * NBITS==0, thus we do a plain copy here.
+ */
+ for (i = 0; i < x->nlimbs; i++)
+ x->d[i] = a->d[i];
+ }
+ }
+ }
+ MPN_NORMALIZE(x->d, x->nlimbs);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_rshift);