From 836b2fe544a5e9b5ce116622cb36fba33838c6fd Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 01:33:23 -0700 Subject: selftests/bpf: Check that JMP32 pointer vs zero jumps are not predicted Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which the verifier used to skip, contains an out of bounds map value access, hence w/o the previous patch the program is accepted. See previous patch for detailed description. Reported-by: Nicholas Carlini Suggested-by: Nicholas Carlini Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- io_uring/memmap.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 io_uring/memmap.h (limited to 'io_uring/memmap.h') diff --git a/io_uring/memmap.h b/io_uring/memmap.h new file mode 100644 index 000000000..f4cfbb6b9 --- /dev/null +++ b/io_uring/memmap.h @@ -0,0 +1,52 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef IO_URING_MEMMAP_H +#define IO_URING_MEMMAP_H + +#define IORING_MAP_OFF_PARAM_REGION 0x20000000ULL +#define IORING_MAP_OFF_ZCRX_REGION 0x30000000ULL + +#define IORING_OFF_ZCRX_SHIFT 16 + +struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages); + +#ifndef CONFIG_MMU +unsigned int io_uring_nommu_mmap_capabilities(struct file *file); +#endif +unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags); +int io_uring_mmap(struct file *file, struct vm_area_struct *vma); + +void io_free_region(struct user_struct *user, struct io_mapped_region *mr); +int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr, + struct io_uring_region_desc *reg, + unsigned long mmap_offset); + +static inline void *io_region_get_ptr(struct io_mapped_region *mr) +{ + return mr->ptr; +} + +static inline bool io_region_is_set(struct io_mapped_region *mr) +{ + return !!mr->nr_pages; +} + +static inline void io_region_publish(struct io_ring_ctx *ctx, + struct io_mapped_region *src_region, + struct io_mapped_region *dst_region) +{ + /* + * Once published mmap can find it without holding only the ->mmap_lock + * and not ->uring_lock. + */ + guard(mutex)(&ctx->mmap_lock); + *dst_region = *src_region; +} + +static inline size_t io_region_size(struct io_mapped_region *mr) +{ + return (size_t) mr->nr_pages << PAGE_SHIFT; +} + +#endif -- cgit v1.3.1