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authorLinus Torvalds <[email protected]>2025-07-30 16:58:50 +0000
committerLinus Torvalds <[email protected]>2025-07-30 16:58:50 +0000
commitd9104cec3e8fe4b458b74709853231385779001f (patch)
tree1ffc3baa0e963d3301765a5d6cbd5410c8796ee4 /tools/testing/selftests/bpf/progs/mem_rdonly_untrusted.c
parentMerge tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ne... (diff)
parentMerge branch 'bpf-show-precise-rejected-function-when-attaching-to-__noreturn... (diff)
downloadkernel-d9104cec3e8fe4b458b74709853231385779001f.tar.gz
kernel-d9104cec3e8fe4b458b74709853231385779001f.zip
Merge tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov: - Remove usermode driver (UMD) framework (Thomas Weißschuh) - Introduce Strongly Connected Component (SCC) in the verifier to detect loops and refine register liveness (Eduard Zingerman) - Allow 'void *' cast using bpf_rdonly_cast() and corresponding '__arg_untrusted' for global function parameters (Eduard Zingerman) - Improve precision for BPF_ADD and BPF_SUB operations in the verifier (Harishankar Vishwanathan) - Teach the verifier that constant pointer to a map cannot be NULL (Ihor Solodrai) - Introduce BPF streams for error reporting of various conditions detected by BPF runtime (Kumar Kartikeya Dwivedi) - Teach the verifier to insert runtime speculation barrier (lfence on x86) to mitigate speculative execution instead of rejecting the programs (Luis Gerhorst) - Various improvements for 'veristat' (Mykyta Yatsenko) - For CONFIG_DEBUG_KERNEL config warn on internal verifier errors to improve bug detection by syzbot (Paul Chaignon) - Support BPF private stack on arm64 (Puranjay Mohan) - Introduce bpf_cgroup_read_xattr() kfunc to read xattr of cgroup's node (Song Liu) - Introduce kfuncs for read-only string opreations (Viktor Malik) - Implement show_fdinfo() for bpf_links (Tao Chen) - Reduce verifier's stack consumption (Yonghong Song) - Implement mprog API for cgroup-bpf programs (Yonghong Song) * tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (192 commits) selftests/bpf: Migrate fexit_noreturns case into tracing_failure test suite selftests/bpf: Add selftest for attaching tracing programs to functions in deny list bpf: Add log for attaching tracing programs to functions in deny list bpf: Show precise rejected function when attaching fexit/fmod_ret to __noreturn functions bpf: Fix various typos in verifier.c comments bpf: Add third round of bounds deduction selftests/bpf: Test invariants on JSLT crossing sign selftests/bpf: Test cross-sign 64bits range refinement selftests/bpf: Update reg_bound range refinement logic bpf: Improve bounds when s64 crosses sign boundary bpf: Simplify bounds refinement from s32 selftests/bpf: Enable private stack tests for arm64 bpf, arm64: JIT support for private stack bpf: Move bpf_jit_get_prog_name() to core.c bpf, arm64: Fix fp initialization for exception boundary umd: Remove usermode driver framework bpf/preload: Don't select USERMODE_DRIVER selftests/bpf: Fix test dynptr/test_dynptr_memset_xdp_chunks failure selftests/bpf: Fix test dynptr/test_dynptr_copy_xdp failure selftests/bpf: Increase xdp data size for arm64 64K page size ...
Diffstat (limited to 'tools/testing/selftests/bpf/progs/mem_rdonly_untrusted.c')
-rw-r--r--tools/testing/selftests/bpf/progs/mem_rdonly_untrusted.c229
1 files changed, 229 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/mem_rdonly_untrusted.c b/tools/testing/selftests/bpf/progs/mem_rdonly_untrusted.c
new file mode 100644
index 000000000000..4f94c971ae86
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/mem_rdonly_untrusted.c
@@ -0,0 +1,229 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <vmlinux.h>
+#include <bpf/bpf_core_read.h>
+#include "bpf_misc.h"
+#include "../test_kmods/bpf_testmod_kfunc.h"
+
+SEC("tp_btf/sys_enter")
+__success
+__log_level(2)
+__msg("r8 = *(u64 *)(r7 +0) ; R7_w=ptr_nameidata(off={{[0-9]+}}) R8_w=rdonly_untrusted_mem(sz=0)")
+__msg("r9 = *(u8 *)(r8 +0) ; R8_w=rdonly_untrusted_mem(sz=0) R9_w=scalar")
+int btf_id_to_ptr_mem(void *ctx)
+{
+ struct task_struct *task;
+ struct nameidata *idata;
+ u64 ret, off;
+
+ task = bpf_get_current_task_btf();
+ idata = task->nameidata;
+ off = bpf_core_field_offset(struct nameidata, pathname);
+ /*
+ * asm block to have reliable match target for __msg, equivalent of:
+ * ret = task->nameidata->pathname[0];
+ */
+ asm volatile (
+ "r7 = %[idata];"
+ "r7 += %[off];"
+ "r8 = *(u64 *)(r7 + 0);"
+ "r9 = *(u8 *)(r8 + 0);"
+ "%[ret] = r9;"
+ : [ret]"=r"(ret)
+ : [idata]"r"(idata),
+ [off]"r"(off)
+ : "r7", "r8", "r9");
+ return ret;
+}
+
+SEC("socket")
+__success
+__retval(0)
+int ldx_is_ok_bad_addr(void *ctx)
+{
+ char *p;
+
+ if (!bpf_core_enum_value_exists(enum bpf_features, BPF_FEAT_RDONLY_CAST_TO_VOID))
+ return 42;
+
+ p = bpf_rdonly_cast(0, 0);
+ return p[0x7fff];
+}
+
+SEC("socket")
+__success
+__retval(1)
+int ldx_is_ok_good_addr(void *ctx)
+{
+ int v, *p;
+
+ v = 1;
+ p = bpf_rdonly_cast(&v, 0);
+ return *p;
+}
+
+SEC("socket")
+__success
+int offset_not_tracked(void *ctx)
+{
+ int *p, i, s;
+
+ p = bpf_rdonly_cast(0, 0);
+ s = 0;
+ bpf_for(i, 0, 1000 * 1000 * 1000) {
+ p++;
+ s += *p;
+ }
+ return s;
+}
+
+SEC("socket")
+__failure
+__msg("cannot write into rdonly_untrusted_mem")
+int stx_not_ok(void *ctx)
+{
+ int v, *p;
+
+ v = 1;
+ p = bpf_rdonly_cast(&v, 0);
+ *p = 1;
+ return 0;
+}
+
+SEC("socket")
+__failure
+__msg("cannot write into rdonly_untrusted_mem")
+int atomic_not_ok(void *ctx)
+{
+ int v, *p;
+
+ v = 1;
+ p = bpf_rdonly_cast(&v, 0);
+ __sync_fetch_and_add(p, 1);
+ return 0;
+}
+
+SEC("socket")
+__failure
+__msg("cannot write into rdonly_untrusted_mem")
+int atomic_rmw_not_ok(void *ctx)
+{
+ long v, *p;
+
+ v = 1;
+ p = bpf_rdonly_cast(&v, 0);
+ return __sync_val_compare_and_swap(p, 0, 42);
+}
+
+SEC("socket")
+__failure
+__msg("invalid access to memory, mem_size=0 off=0 size=4")
+__msg("R1 min value is outside of the allowed memory range")
+int kfunc_param_not_ok(void *ctx)
+{
+ int *p;
+
+ p = bpf_rdonly_cast(0, 0);
+ bpf_kfunc_trusted_num_test(p);
+ return 0;
+}
+
+SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
+__failure
+__msg("R1 type=rdonly_untrusted_mem expected=")
+int helper_param_not_ok(void *ctx)
+{
+ char *p;
+
+ p = bpf_rdonly_cast(0, 0);
+ /*
+ * Any helper with ARG_CONST_SIZE_OR_ZERO constraint will do,
+ * the most permissive constraint
+ */
+ bpf_copy_from_user(p, 0, (void *)42);
+ return 0;
+}
+
+static __noinline u64 *get_some_addr(void)
+{
+ if (bpf_get_prandom_u32())
+ return bpf_rdonly_cast(0, bpf_core_type_id_kernel(struct sock));
+ else
+ return bpf_rdonly_cast(0, 0);
+}
+
+SEC("socket")
+__success
+__retval(0)
+int mixed_mem_type(void *ctx)
+{
+ u64 *p;
+
+ /* Try to avoid compiler hoisting load to if branches by using __noinline func. */
+ p = get_some_addr();
+ return *p;
+}
+
+__attribute__((__aligned__(8)))
+u8 global[] = {
+ 0x11, 0x22, 0x33, 0x44,
+ 0x55, 0x66, 0x77, 0x88,
+ 0x99
+};
+
+__always_inline
+static u64 combine(void *p)
+{
+ u64 acc;
+
+ acc = 0;
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+ acc |= (*(u64 *)p >> 56) << 24;
+ acc |= (*(u32 *)p >> 24) << 16;
+ acc |= (*(u16 *)p >> 8) << 8;
+ acc |= *(u8 *)p;
+#else
+ acc |= (*(u64 *)p & 0xff) << 24;
+ acc |= (*(u32 *)p & 0xff) << 16;
+ acc |= (*(u16 *)p & 0xff) << 8;
+ acc |= *(u8 *)p;
+#endif
+ return acc;
+}
+
+SEC("socket")
+__retval(0x88442211)
+int diff_size_access(void *ctx)
+{
+ return combine(bpf_rdonly_cast(&global, 0));
+}
+
+SEC("socket")
+__retval(0x99553322)
+int misaligned_access(void *ctx)
+{
+ return combine(bpf_rdonly_cast(&global, 0) + 1);
+}
+
+__weak int return_one(void)
+{
+ return 1;
+}
+
+SEC("socket")
+__success
+__retval(1)
+int null_check(void *ctx)
+{
+ int *p;
+
+ p = bpf_rdonly_cast(0, 0);
+ if (p == 0)
+ /* make this a function call to avoid compiler
+ * moving r0 assignment before check.
+ */
+ return return_one();
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";