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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/kfifo.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/kfifo.c')
-rw-r--r--lib/kfifo.c595
1 files changed, 595 insertions, 0 deletions
diff --git a/lib/kfifo.c b/lib/kfifo.c
new file mode 100644
index 000000000..2633f9cc3
--- /dev/null
+++ b/lib/kfifo.c
@@ -0,0 +1,595 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * A generic kernel FIFO implementation
+ *
+ * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net>
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/kfifo.h>
+#include <linux/log2.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+/*
+ * internal helper to calculate the unused elements in a fifo
+ */
+static inline unsigned int kfifo_unused(struct __kfifo *fifo)
+{
+ return (fifo->mask + 1) - (fifo->in - fifo->out);
+}
+
+int __kfifo_alloc_node(struct __kfifo *fifo, unsigned int size,
+ size_t esize, gfp_t gfp_mask, int node)
+{
+ /*
+ * round up to the next power of 2, since our 'let the indices
+ * wrap' technique works only in this case.
+ */
+ size = roundup_pow_of_two(size);
+
+ fifo->in = 0;
+ fifo->out = 0;
+ fifo->esize = esize;
+
+ if (size < 2) {
+ fifo->data = NULL;
+ fifo->mask = 0;
+ return -EINVAL;
+ }
+
+ fifo->data = kmalloc_array_node(size, esize, gfp_mask, node);
+
+ if (!fifo->data) {
+ fifo->mask = 0;
+ return -ENOMEM;
+ }
+ fifo->mask = size - 1;
+
+ return 0;
+}
+EXPORT_SYMBOL(__kfifo_alloc_node);
+
+void __kfifo_free(struct __kfifo *fifo)
+{
+ kfree(fifo->data);
+ fifo->in = 0;
+ fifo->out = 0;
+ fifo->esize = 0;
+ fifo->data = NULL;
+ fifo->mask = 0;
+}
+EXPORT_SYMBOL(__kfifo_free);
+
+int __kfifo_init(struct __kfifo *fifo, void *buffer,
+ unsigned int size, size_t esize)
+{
+ size /= esize;
+
+ if (!is_power_of_2(size))
+ size = rounddown_pow_of_two(size);
+
+ fifo->in = 0;
+ fifo->out = 0;
+ fifo->esize = esize;
+ fifo->data = buffer;
+
+ if (size < 2) {
+ fifo->mask = 0;
+ return -EINVAL;
+ }
+ fifo->mask = size - 1;
+
+ return 0;
+}
+EXPORT_SYMBOL(__kfifo_init);
+
+static void kfifo_copy_in(struct __kfifo *fifo, const void *src,
+ unsigned int len, unsigned int off)
+{
+ unsigned int size = fifo->mask + 1;
+ unsigned int esize = fifo->esize;
+ unsigned int l;
+
+ off &= fifo->mask;
+ if (esize != 1) {
+ off *= esize;
+ size *= esize;
+ len *= esize;
+ }
+ l = min(len, size - off);
+
+ memcpy(fifo->data + off, src, l);
+ memcpy(fifo->data, src + l, len - l);
+ /*
+ * make sure that the data in the fifo is up to date before
+ * incrementing the fifo->in index counter
+ */
+ smp_wmb();
+}
+
+unsigned int __kfifo_in(struct __kfifo *fifo,
+ const void *buf, unsigned int len)
+{
+ unsigned int l;
+
+ l = kfifo_unused(fifo);
+ if (len > l)
+ len = l;
+
+ kfifo_copy_in(fifo, buf, len, fifo->in);
+ fifo->in += len;
+ return len;
+}
+EXPORT_SYMBOL(__kfifo_in);
+
+static void kfifo_copy_out(struct __kfifo *fifo, void *dst,
+ unsigned int len, unsigned int off)
+{
+ unsigned int size = fifo->mask + 1;
+ unsigned int esize = fifo->esize;
+ unsigned int l;
+
+ off &= fifo->mask;
+ if (esize != 1) {
+ off *= esize;
+ size *= esize;
+ len *= esize;
+ }
+ l = min(len, size - off);
+
+ memcpy(dst, fifo->data + off, l);
+ memcpy(dst + l, fifo->data, len - l);
+ /*
+ * make sure that the data is copied before
+ * incrementing the fifo->out index counter
+ */
+ smp_wmb();
+}
+
+unsigned int __kfifo_out_peek(struct __kfifo *fifo,
+ void *buf, unsigned int len)
+{
+ unsigned int l;
+
+ l = fifo->in - fifo->out;
+ if (len > l)
+ len = l;
+
+ kfifo_copy_out(fifo, buf, len, fifo->out);
+ return len;
+}
+EXPORT_SYMBOL(__kfifo_out_peek);
+
+unsigned int __kfifo_out_linear(struct __kfifo *fifo,
+ unsigned int *tail, unsigned int n)
+{
+ unsigned int size = fifo->mask + 1;
+ unsigned int off = fifo->out & fifo->mask;
+
+ if (tail)
+ *tail = off;
+
+ return min3(n, fifo->in - fifo->out, size - off);
+}
+EXPORT_SYMBOL(__kfifo_out_linear);
+
+unsigned int __kfifo_out(struct __kfifo *fifo,
+ void *buf, unsigned int len)
+{
+ len = __kfifo_out_peek(fifo, buf, len);
+ fifo->out += len;
+ return len;
+}
+EXPORT_SYMBOL(__kfifo_out);
+
+static unsigned long kfifo_copy_from_user(struct __kfifo *fifo,
+ const void __user *from, unsigned int len, unsigned int off,
+ unsigned int *copied)
+{
+ unsigned int size = fifo->mask + 1;
+ unsigned int esize = fifo->esize;
+ unsigned int l;
+ unsigned long ret;
+
+ off &= fifo->mask;
+ if (esize != 1) {
+ off *= esize;
+ size *= esize;
+ len *= esize;
+ }
+ l = min(len, size - off);
+
+ ret = copy_from_user(fifo->data + off, from, l);
+ if (unlikely(ret))
+ ret = DIV_ROUND_UP(ret + len - l, esize);
+ else {
+ ret = copy_from_user(fifo->data, from + l, len - l);
+ if (unlikely(ret))
+ ret = DIV_ROUND_UP(ret, esize);
+ }
+ /*
+ * make sure that the data in the fifo is up to date before
+ * incrementing the fifo->in index counter
+ */
+ smp_wmb();
+ *copied = len - ret * esize;
+ /* return the number of elements which are not copied */
+ return ret;
+}
+
+int __kfifo_from_user(struct __kfifo *fifo, const void __user *from,
+ unsigned long len, unsigned int *copied)
+{
+ unsigned int l;
+ unsigned long ret;
+ unsigned int esize = fifo->esize;
+ int err;
+
+ if (esize != 1)
+ len /= esize;
+
+ l = kfifo_unused(fifo);
+ if (len > l)
+ len = l;
+
+ ret = kfifo_copy_from_user(fifo, from, len, fifo->in, copied);
+ if (unlikely(ret)) {
+ len -= ret;
+ err = -EFAULT;
+ } else
+ err = 0;
+ fifo->in += len;
+ return err;
+}
+EXPORT_SYMBOL(__kfifo_from_user);
+
+static unsigned long kfifo_copy_to_user(struct __kfifo *fifo, void __user *to,
+ unsigned int len, unsigned int off, unsigned int *copied)
+{
+ unsigned int l;
+ unsigned long ret;
+ unsigned int size = fifo->mask + 1;
+ unsigned int esize = fifo->esize;
+
+ off &= fifo->mask;
+ if (esize != 1) {
+ off *= esize;
+ size *= esize;
+ len *= esize;
+ }
+ l = min(len, size - off);
+
+ ret = copy_to_user(to, fifo->data + off, l);
+ if (unlikely(ret))
+ ret = DIV_ROUND_UP(ret + len - l, esize);
+ else {
+ ret = copy_to_user(to + l, fifo->data, len - l);
+ if (unlikely(ret))
+ ret = DIV_ROUND_UP(ret, esize);
+ }
+ /*
+ * make sure that the data is copied before
+ * incrementing the fifo->out index counter
+ */
+ smp_wmb();
+ *copied = len - ret * esize;
+ /* return the number of elements which are not copied */
+ return ret;
+}
+
+int __kfifo_to_user(struct __kfifo *fifo, void __user *to,
+ unsigned long len, unsigned int *copied)
+{
+ unsigned int l;
+ unsigned long ret;
+ unsigned int esize = fifo->esize;
+ int err;
+
+ if (esize != 1)
+ len /= esize;
+
+ l = fifo->in - fifo->out;
+ if (len > l)
+ len = l;
+ ret = kfifo_copy_to_user(fifo, to, len, fifo->out, copied);
+ if (unlikely(ret)) {
+ len -= ret;
+ err = -EFAULT;
+ } else
+ err = 0;
+ fifo->out += len;
+ return err;
+}
+EXPORT_SYMBOL(__kfifo_to_user);
+
+static unsigned int setup_sgl_buf(struct __kfifo *fifo, struct scatterlist *sgl,
+ unsigned int data_offset, int nents,
+ unsigned int len, dma_addr_t dma)
+{
+ const void *buf = fifo->data + data_offset;
+
+ if (!nents || !len)
+ return 0;
+
+ sg_set_buf(sgl, buf, len);
+
+ if (dma != DMA_MAPPING_ERROR) {
+ sg_dma_address(sgl) = dma + data_offset;
+ sg_dma_len(sgl) = len;
+ }
+
+ return 1;
+}
+
+static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl,
+ int nents, unsigned int len, unsigned int off, dma_addr_t dma)
+{
+ unsigned int size = fifo->mask + 1;
+ unsigned int esize = fifo->esize;
+ unsigned int len_to_end;
+ unsigned int n;
+
+ off &= fifo->mask;
+ if (esize != 1) {
+ off *= esize;
+ size *= esize;
+ len *= esize;
+ }
+ len_to_end = min(len, size - off);
+
+ n = setup_sgl_buf(fifo, sgl, off, nents, len_to_end, dma);
+ n += setup_sgl_buf(fifo, sgl + n, 0, nents - n, len - len_to_end, dma);
+
+ return n;
+}
+
+unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len,
+ dma_addr_t dma)
+{
+ unsigned int l;
+
+ l = kfifo_unused(fifo);
+ if (len > l)
+ len = l;
+
+ return setup_sgl(fifo, sgl, nents, len, fifo->in, dma);
+}
+EXPORT_SYMBOL(__kfifo_dma_in_prepare);
+
+unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len,
+ dma_addr_t dma)
+{
+ unsigned int l;
+
+ l = fifo->in - fifo->out;
+ if (len > l)
+ len = l;
+
+ return setup_sgl(fifo, sgl, nents, len, fifo->out, dma);
+}
+EXPORT_SYMBOL(__kfifo_dma_out_prepare);
+
+unsigned int __kfifo_max_r(unsigned int len, size_t recsize)
+{
+ unsigned int max = (1 << (recsize << 3)) - 1;
+
+ if (len > max)
+ return max;
+ return len;
+}
+EXPORT_SYMBOL(__kfifo_max_r);
+
+#define __KFIFO_PEEK(data, out, mask) \
+ ((data)[(out) & (mask)])
+/*
+ * __kfifo_peek_n internal helper function for determinate the length of
+ * the next record in the fifo
+ */
+static unsigned int __kfifo_peek_n(struct __kfifo *fifo, size_t recsize)
+{
+ unsigned int l;
+ unsigned int mask = fifo->mask;
+ unsigned char *data = fifo->data;
+
+ l = __KFIFO_PEEK(data, fifo->out, mask);
+
+ if (--recsize)
+ l |= __KFIFO_PEEK(data, fifo->out + 1, mask) << 8;
+
+ return l;
+}
+
+#define __KFIFO_POKE(data, in, mask, val) \
+ ( \
+ (data)[(in) & (mask)] = (unsigned char)(val) \
+ )
+
+/*
+ * __kfifo_poke_n internal helper function for storing the length of
+ * the record into the fifo
+ */
+static void __kfifo_poke_n(struct __kfifo *fifo, unsigned int n, size_t recsize)
+{
+ unsigned int mask = fifo->mask;
+ unsigned char *data = fifo->data;
+
+ __KFIFO_POKE(data, fifo->in, mask, n);
+
+ if (recsize > 1)
+ __KFIFO_POKE(data, fifo->in + 1, mask, n >> 8);
+}
+
+unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize)
+{
+ return __kfifo_peek_n(fifo, recsize);
+}
+EXPORT_SYMBOL(__kfifo_len_r);
+
+unsigned int __kfifo_in_r(struct __kfifo *fifo, const void *buf,
+ unsigned int len, size_t recsize)
+{
+ if (len + recsize > kfifo_unused(fifo))
+ return 0;
+
+ __kfifo_poke_n(fifo, len, recsize);
+
+ kfifo_copy_in(fifo, buf, len, fifo->in + recsize);
+ fifo->in += len + recsize;
+ return len;
+}
+EXPORT_SYMBOL(__kfifo_in_r);
+
+static unsigned int kfifo_out_copy_r(struct __kfifo *fifo,
+ void *buf, unsigned int len, size_t recsize, unsigned int *n)
+{
+ *n = __kfifo_peek_n(fifo, recsize);
+
+ if (len > *n)
+ len = *n;
+
+ kfifo_copy_out(fifo, buf, len, fifo->out + recsize);
+ return len;
+}
+
+unsigned int __kfifo_out_peek_r(struct __kfifo *fifo, void *buf,
+ unsigned int len, size_t recsize)
+{
+ unsigned int n;
+
+ if (fifo->in == fifo->out)
+ return 0;
+
+ return kfifo_out_copy_r(fifo, buf, len, recsize, &n);
+}
+EXPORT_SYMBOL(__kfifo_out_peek_r);
+
+unsigned int __kfifo_out_linear_r(struct __kfifo *fifo,
+ unsigned int *tail, unsigned int n, size_t recsize)
+{
+ if (fifo->in == fifo->out)
+ return 0;
+
+ if (tail)
+ *tail = fifo->out + recsize;
+
+ return min(n, __kfifo_peek_n(fifo, recsize));
+}
+EXPORT_SYMBOL(__kfifo_out_linear_r);
+
+unsigned int __kfifo_out_r(struct __kfifo *fifo, void *buf,
+ unsigned int len, size_t recsize)
+{
+ unsigned int n;
+
+ if (fifo->in == fifo->out)
+ return 0;
+
+ len = kfifo_out_copy_r(fifo, buf, len, recsize, &n);
+ fifo->out += n + recsize;
+ return len;
+}
+EXPORT_SYMBOL(__kfifo_out_r);
+
+void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize)
+{
+ unsigned int n;
+
+ n = __kfifo_peek_n(fifo, recsize);
+ fifo->out += n + recsize;
+}
+EXPORT_SYMBOL(__kfifo_skip_r);
+
+int __kfifo_from_user_r(struct __kfifo *fifo, const void __user *from,
+ unsigned long len, unsigned int *copied, size_t recsize)
+{
+ unsigned long ret;
+
+ len = __kfifo_max_r(len, recsize);
+
+ if (len + recsize > kfifo_unused(fifo)) {
+ *copied = 0;
+ return 0;
+ }
+
+ __kfifo_poke_n(fifo, len, recsize);
+
+ ret = kfifo_copy_from_user(fifo, from, len, fifo->in + recsize, copied);
+ if (unlikely(ret)) {
+ *copied = 0;
+ return -EFAULT;
+ }
+ fifo->in += len + recsize;
+ return 0;
+}
+EXPORT_SYMBOL(__kfifo_from_user_r);
+
+int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to,
+ unsigned long len, unsigned int *copied, size_t recsize)
+{
+ unsigned long ret;
+ unsigned int n;
+
+ if (fifo->in == fifo->out) {
+ *copied = 0;
+ return 0;
+ }
+
+ n = __kfifo_peek_n(fifo, recsize);
+ if (len > n)
+ len = n;
+
+ ret = kfifo_copy_to_user(fifo, to, len, fifo->out + recsize, copied);
+ if (unlikely(ret)) {
+ *copied = 0;
+ return -EFAULT;
+ }
+ fifo->out += n + recsize;
+ return 0;
+}
+EXPORT_SYMBOL(__kfifo_to_user_r);
+
+unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len, size_t recsize,
+ dma_addr_t dma)
+{
+ BUG_ON(!nents);
+
+ len = __kfifo_max_r(len, recsize);
+
+ if (len + recsize > kfifo_unused(fifo))
+ return 0;
+
+ return setup_sgl(fifo, sgl, nents, len, fifo->in + recsize, dma);
+}
+EXPORT_SYMBOL(__kfifo_dma_in_prepare_r);
+
+void __kfifo_dma_in_finish_r(struct __kfifo *fifo,
+ unsigned int len, size_t recsize)
+{
+ len = __kfifo_max_r(len, recsize);
+ __kfifo_poke_n(fifo, len, recsize);
+ fifo->in += len + recsize;
+}
+EXPORT_SYMBOL(__kfifo_dma_in_finish_r);
+
+unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len, size_t recsize,
+ dma_addr_t dma)
+{
+ BUG_ON(!nents);
+
+ len = __kfifo_max_r(len, recsize);
+
+ if (len + recsize > fifo->in - fifo->out)
+ return 0;
+
+ return setup_sgl(fifo, sgl, nents, len, fifo->out + recsize, dma);
+}
+EXPORT_SYMBOL(__kfifo_dma_out_prepare_r);
+