From 5c5240d020615f13331f4e2c559186125eddc7d3 Mon Sep 17 00:00:00 2001 From: Puranjay Mohan Date: Thu, 11 Sep 2025 14:58:02 +0000 Subject: bpf: Report arena faults to BPF stderr Begin reporting arena page faults and the faulting address to BPF program's stderr, this patch adds support in the arm64 and x86-64 JITs, support for other archs can be added later. The fault handlers receive the 32 bit address in the arena region so the upper 32 bits of user_vm_start is added to it before printing the address. This is what the user would expect to see as this is what is printed by bpf_printk() is you pass it an address returned by bpf_arena_alloc_pages(); Signed-off-by: Puranjay Mohan Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20250911145808.58042-4-puranjay@kernel.org Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index d133171c4d2a..41f776071ff5 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2881,6 +2881,7 @@ void bpf_dynptr_init(struct bpf_dynptr_kern *ptr, void *data, enum bpf_dynptr_type type, u32 offset, u32 size); void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr); void bpf_dynptr_set_rdonly(struct bpf_dynptr_kern *ptr); +void bpf_prog_report_arena_violation(bool write, unsigned long addr, unsigned long fault_ip); #else /* !CONFIG_BPF_SYSCALL */ static inline struct bpf_prog *bpf_prog_get(u32 ufd) @@ -3168,6 +3169,11 @@ static inline void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr) static inline void bpf_dynptr_set_rdonly(struct bpf_dynptr_kern *ptr) { } + +static inline void bpf_prog_report_arena_violation(bool write, unsigned long addr, + unsigned long fault_ip) +{ +} #endif /* CONFIG_BPF_SYSCALL */ static __always_inline int -- cgit v1.2.3