From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id Add tests where two packet pointers share an id and tightening one pointer's umax from its var_off would put it less than their constant distance from the other's umax: with an index & 0x38 capped at 50, the base pointer keeps umax 50, so the pointer 8 bytes further on must keep umax 58, even though its known bits allow at most 56. These refused a valid program or accepted an out-of-bounds access before the fix: - check the advanced copy, load through the base: valid, was refused; - check the base, load the byte at base + 1 through a copy advanced by 8: was accepted; - check base + 4, load 4 bytes at base + 2 through base + 8: reads two bytes past the checked range, was accepted; - the same as the second with data_meta pointers checked against data: was accepted. These pass with and without the fix and cover nearby paths: - subtract an unknown scalar from a checked pointer and load below it (the range is kept across a new id); - reach a load through two paths whose checks cover 8 and 7 bytes after the loaded pointer; the second path must not be pruned by the first; - spill a copy of a pointer, check the pointer, fill the copy and load one byte past the checked range: the load is refused, and the copy has the range of the check. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- include/trace/events/percpu.h | 137 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 137 insertions(+) create mode 100644 include/trace/events/percpu.h (limited to 'include/trace/events/percpu.h') diff --git a/include/trace/events/percpu.h b/include/trace/events/percpu.h new file mode 100644 index 000000000..5b8211ca8 --- /dev/null +++ b/include/trace/events/percpu.h @@ -0,0 +1,137 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM percpu + +#if !defined(_TRACE_PERCPU_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_PERCPU_H + +#include +#include + +TRACE_EVENT(percpu_alloc_percpu, + + TP_PROTO(unsigned long call_site, + bool reserved, bool is_atomic, size_t size, + size_t align, void *base_addr, int off, + void __percpu *ptr, size_t bytes_alloc, gfp_t gfp_flags), + + TP_ARGS(call_site, reserved, is_atomic, size, align, base_addr, off, + ptr, bytes_alloc, gfp_flags), + + TP_STRUCT__entry( + __field( unsigned long, call_site ) + __field( bool, reserved ) + __field( bool, is_atomic ) + __field( size_t, size ) + __field( size_t, align ) + __field( void *, base_addr ) + __field( int, off ) + __field( void __percpu *, ptr ) + __field( size_t, bytes_alloc ) + __field( unsigned long, gfp_flags ) + ), + TP_fast_assign( + __entry->call_site = call_site; + __entry->reserved = reserved; + __entry->is_atomic = is_atomic; + __entry->size = size; + __entry->align = align; + __entry->base_addr = base_addr; + __entry->off = off; + __entry->ptr = ptr; + __entry->bytes_alloc = bytes_alloc; + __entry->gfp_flags = (__force unsigned long)gfp_flags; + ), + + TP_printk("call_site=%pS reserved=%d is_atomic=%d size=%zu align=%zu base_addr=%p off=%d ptr=%p bytes_alloc=%zu gfp_flags=%s", + (void *)__entry->call_site, + __entry->reserved, __entry->is_atomic, + __entry->size, __entry->align, + __entry->base_addr, __entry->off, __entry->ptr, + __entry->bytes_alloc, show_gfp_flags(__entry->gfp_flags)) +); + +TRACE_EVENT(percpu_free_percpu, + + TP_PROTO(void *base_addr, int off, void __percpu *ptr), + + TP_ARGS(base_addr, off, ptr), + + TP_STRUCT__entry( + __field( void *, base_addr ) + __field( int, off ) + __field( void __percpu *, ptr ) + ), + + TP_fast_assign( + __entry->base_addr = base_addr; + __entry->off = off; + __entry->ptr = ptr; + ), + + TP_printk("base_addr=%p off=%d ptr=%p", + __entry->base_addr, __entry->off, __entry->ptr) +); + +TRACE_EVENT(percpu_alloc_percpu_fail, + + TP_PROTO(bool reserved, bool is_atomic, size_t size, size_t align), + + TP_ARGS(reserved, is_atomic, size, align), + + TP_STRUCT__entry( + __field( bool, reserved ) + __field( bool, is_atomic ) + __field( size_t, size ) + __field( size_t, align ) + ), + + TP_fast_assign( + __entry->reserved = reserved; + __entry->is_atomic = is_atomic; + __entry->size = size; + __entry->align = align; + ), + + TP_printk("reserved=%d is_atomic=%d size=%zu align=%zu", + __entry->reserved, __entry->is_atomic, + __entry->size, __entry->align) +); + +TRACE_EVENT(percpu_create_chunk, + + TP_PROTO(void *base_addr), + + TP_ARGS(base_addr), + + TP_STRUCT__entry( + __field( void *, base_addr ) + ), + + TP_fast_assign( + __entry->base_addr = base_addr; + ), + + TP_printk("base_addr=%p", __entry->base_addr) +); + +TRACE_EVENT(percpu_destroy_chunk, + + TP_PROTO(void *base_addr), + + TP_ARGS(base_addr), + + TP_STRUCT__entry( + __field( void *, base_addr ) + ), + + TP_fast_assign( + __entry->base_addr = base_addr; + ), + + TP_printk("base_addr=%p", __entry->base_addr) +); + +#endif /* _TRACE_PERCPU_H */ + +#include -- cgit v1.3.1