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Diffstat (limited to 'kernel')
-rw-r--r--kernel/bpf/helpers.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index d913a8f1fbd9..018985ebc5ce 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -2851,6 +2851,8 @@ struct bpf_iter_bits {
__u64 __opaque[2];
} __aligned(8);
+#define BITS_ITER_NR_WORDS_MAX 511
+
struct bpf_iter_bits_kern {
union {
unsigned long *bits;
@@ -2865,7 +2867,8 @@ struct bpf_iter_bits_kern {
* @it: The new bpf_iter_bits to be created
* @unsafe_ptr__ign: A pointer pointing to a memory area to be iterated over
* @nr_words: The size of the specified memory area, measured in 8-byte units.
- * Due to the limitation of memalloc, it can't be greater than 512.
+ * The maximum value of @nr_words is @BITS_ITER_NR_WORDS_MAX. This limit may be
+ * further reduced by the BPF memory allocator implementation.
*
* This function initializes a new bpf_iter_bits structure for iterating over
* a memory area which is specified by the @unsafe_ptr__ign and @nr_words. It
@@ -2892,6 +2895,8 @@ bpf_iter_bits_new(struct bpf_iter_bits *it, const u64 *unsafe_ptr__ign, u32 nr_w
if (!unsafe_ptr__ign || !nr_words)
return -EINVAL;
+ if (nr_words > BITS_ITER_NR_WORDS_MAX)
+ return -E2BIG;
/* Optimization for u64 mask */
if (nr_bits == 64) {
@@ -2903,6 +2908,9 @@ bpf_iter_bits_new(struct bpf_iter_bits *it, const u64 *unsafe_ptr__ign, u32 nr_w
return 0;
}
+ if (bpf_mem_alloc_check_size(false, nr_bytes))
+ return -E2BIG;
+
/* Fallback to memalloc */
kit->bits = bpf_mem_alloc(&bpf_global_ma, nr_bytes);
if (!kit->bits)