- Linux-kselftest-mirror - lists.linaro.org

by Sagi Shahar

This is v11 of the TDX selftests. This series is based on v6.17-rc7 Changes from v10 [1]: - Rebased on top of v6.17-rc4. - Addressed minor comments from v10. - Removed code for setting up X86_CR4_OSXMMEXCPT which is not needed for now. - Added call to vm_tdx_load_common_boot_parameters() in "KVM: selftests: Call TDX init when creating a new TDX vm" which was accidentally dropped between v9 and v10 due to code refactoring [1] https://lore.kernel.org/lkml/20250904065453.639610-1-sagis@google.com/#r Ackerley Tng (2): KVM: selftests: Add helpers to init TDX memory and finalize VM KVM: selftests: Add ucall support for TDX Erdem Aktas (2): KVM: selftests: Add TDX boot code KVM: selftests: Add support for TDX TDCALL from guest Isaku Yamahata (2): KVM: selftests: Update kvm_init_vm_address_properties() for TDX KVM: selftests: TDX: Use KVM_TDX_CAPABILITIES to validate TDs' attribute configuration Sagi Shahar (15): KVM: selftests: Allocate pgd in virt_map() as necessary KVM: selftests: Expose functions to get default sregs values KVM: selftests: Expose function to allocate guest vCPU stack KVM: selftests: Expose segment definitons to assembly files KVM: selftests: Add kbuild definitons KVM: selftests: Define structs to pass parameters to TDX boot code KVM: selftests: Set up TDX boot code region KVM: selftests: Set up TDX boot parameters region KVM: selftests: Add helper to initialize TDX VM KVM: selftests: Call TDX init when creating a new TDX vm KVM: selftests: Setup memory regions for TDX on vm creation KVM: selftests: Call KVM_TDX_INIT_VCPU when creating a new TDX vcpu KVM: selftests: Set entry point for TDX guest code KVM: selftests: Add wrapper for TDX MMIO from guest KVM: selftests: Add TDX lifecycle test tools/include/linux/kbuild.h | 18 + tools/testing/selftests/kvm/Makefile.kvm | 32 ++ .../selftests/kvm/include/ucall_common.h | 1 + .../selftests/kvm/include/x86/processor.h | 35 ++ .../selftests/kvm/include/x86/processor_asm.h | 12 + .../selftests/kvm/include/x86/tdx/td_boot.h | 74 ++++ .../kvm/include/x86/tdx/td_boot_asm.h | 16 + .../selftests/kvm/include/x86/tdx/tdcall.h | 34 ++ .../selftests/kvm/include/x86/tdx/tdx.h | 14 + .../selftests/kvm/include/x86/tdx/tdx_util.h | 86 +++++ .../testing/selftests/kvm/include/x86/ucall.h | 6 - tools/testing/selftests/kvm/lib/kvm_util.c | 10 +- .../testing/selftests/kvm/lib/x86/processor.c | 93 +++-- .../selftests/kvm/lib/x86/tdx/td_boot.S | 60 +++ .../kvm/lib/x86/tdx/td_boot_offsets.c | 21 ++ .../selftests/kvm/lib/x86/tdx/tdcall.S | 93 +++++ .../kvm/lib/x86/tdx/tdcall_offsets.c | 16 + tools/testing/selftests/kvm/lib/x86/tdx/tdx.c | 23 ++ .../selftests/kvm/lib/x86/tdx/tdx_util.c | 348 ++++++++++++++++++ tools/testing/selftests/kvm/lib/x86/ucall.c | 46 ++- tools/testing/selftests/kvm/x86/tdx_vm_test.c | 31 ++ 21 files changed, 1029 insertions(+), 40 deletions(-) create mode 100644 tools/include/linux/kbuild.h create mode 100644 tools/testing/selftests/kvm/include/x86/processor_asm.h create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/td_boot.h create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/td_boot_asm.h create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/tdcall.h create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/tdx.h create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h create mode 100644 tools/testing/selftests/kvm/lib/x86/tdx/td_boot.S create mode 100644 tools/testing/selftests/kvm/lib/x86/tdx/td_boot_offsets.c create mode 100644 tools/testing/selftests/kvm/lib/x86/tdx/tdcall.S create mode 100644 tools/testing/selftests/kvm/lib/x86/tdx/tdcall_offsets.c create mode 100644 tools/testing/selftests/kvm/lib/x86/tdx/tdx.c create mode 100644 tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c create mode 100644 tools/testing/selftests/kvm/x86/tdx_vm_test.c -- 2.51.0.536.g15c5d4f767-goog

2 weeks, 4 days

3
32
0 0

[PATCH] selftest: net: fix socklen_t type mismatch in sctp_collision test

by Ankit Khushwaha

Socket APIs like recvfrom(), accept(), and getsockname() expect socklen_t* arg, but tests were using int variables. This causes -Wpointer-sign warnings on platforms where socklen_t is unsigned. Change the variable type from int to socklen_t to resolve the warning and ensure type safety across platforms. warning fixed: sctp_collision.c:62:70: warning: passing 'int *' to parameter of type 'socklen_t *' (aka 'unsigned int *') converts between pointers to integer types with different sign [-Wpointer-sign] 62 | ret = recvfrom(sd, buf, sizeof(buf), 0, (struct sockaddr *)&daddr, &len); | ^~~~ /usr/include/sys/socket.h:165:27: note: passing argument to parameter '__addr_len' here 165 | socklen_t *__restrict __addr_len); | ^ Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- tools/testing/selftests/net/netfilter/sctp_collision.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/netfilter/sctp_collision.c b/tools/testing/selftests/net/netfilter/sctp_collision.c index 21bb1cfd8a85..91df996367e9 100644 --- a/tools/testing/selftests/net/netfilter/sctp_collision.c +++ b/tools/testing/selftests/net/netfilter/sctp_collision.c @@ -9,7 +9,8 @@ int main(int argc, char *argv[]) { struct sockaddr_in saddr = {}, daddr = {}; - int sd, ret, len = sizeof(daddr); + int sd, ret; + socklen_t len = sizeof(daddr); struct timeval tv = {25, 0}; char buf[] = "hello"; -- 2.51.0

2 weeks, 4 days

3
3
0 0

[PATCH v4] selftests/bpf: Change variable types for -Wsign-compare

by Mehdi Ben Hadj Khelifa

This is a follow up patch for commit 495d2d8133fd("selftests/bpf: Attempt to build BPF programs with -Wsign-compare") from Alexei Starovoitov[1] to be able to enable -Wsign-compare C compilation flag for clang since -Wall doesn't add it and BPF programs are built with clang.This has the benefit to catch problematic comparisons in future tests as quoted from the commit message:" int i = -1; unsigned int j = 1; if (i < j) // this is false. long i = -1; unsigned int j = 1; if (i < j) // this is true. C standard for reference: - If either operand is unsigned long the other shall be converted to unsigned long. - Otherwise, if one operand is a long int and the other unsigned int, then if a long int can represent all the values of an unsigned int, the unsigned int shall be converted to a long int; otherwise both operands shall be converted to unsigned long int. - Otherwise, if either operand is long, the other shall be converted to long. - Otherwise, if either operand is unsigned, the other shall be converted to unsigned. Unfortunately clang's -Wsign-compare is very noisy. It complains about (s32)a == (u32)b which is safe and doen't have surprising behavior." This specific patch supresses the following warnings when -Wsign-compare is enabled: 1 warning generated. progs/bpf_iter_bpf_percpu_array_map.c:35:16: warning: comparison of integers of different signs: 'int' and 'const volatile __u32' (aka 'const volatile unsigned int') [-Wsign-compare] 35 | for (i = 0; i < num_cpus; i++) { | ~ ^ ~~~~~~~~ 1 warning generated. progs/bpf_qdisc_fifo.c:93:2: warning: comparison of integers of different signs: 'int' and '__u32' (aka 'unsigned int') [-Wsign-compare] 93 | bpf_for(i, 0, sch->q.qlen) { | ^ ~ ~~~~~~~~~~~ Should be noted that many more similar changes are still needed in order to be able to enable the -Wsign-compare flag since -Werror is enabled and would cause compilation of bpf selftests to fail. [1]. Link:https://github.com/torvalds/linux/commit/495d2d8133fd1407519170a5238f4… Signed-off-by: Mehdi Ben Hadj Khelifa <mehdi.benhadjkhelifa(a)gmail.com> --- Changelog: Changes from v3: -Downsized the patch as suggested by vivek yadav[2]. -Changed the commit message as suggested by Daniel Borkmann[3]. Link:https://lore.kernel.org/all/20250925103559.14876-1-mehdi.benhadjkhelif… Changes from v2: -Split up the patch into a patch series as suggested by vivek -Include only changes to variable types with no casting by my mentor david -Removed the -Wsign-compare in Makefile to avoid compilation errors until adding casting for rest of comparisons. Link:https://lore.kernel.org/bpf/20250924195731.6374-1-mehdi.benhadjkhelifa… Changes from v1: - Fix CI failed builds where it failed due to do missing .c and .h files in my patch for working in mainline. Link:https://lore.kernel.org/bpf/20250924162408.815137-1-mehdi.benhadjkheli… [2]:https://lore.kernel.org/all/CABPSWR7_w3mxr74wCDEF=MYYuG2F_vMJeD-dqotc8MD… [3]:https://lore.kernel.org/all/5ad26663-a3cc-4bf4-9d6f-8213ac8e8ce6@iogearb… .../testing/selftests/bpf/progs/bpf_iter_bpf_percpu_array_map.c | 2 +- tools/testing/selftests/bpf/progs/bpf_qdisc_fifo.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_percpu_array_map.c b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_percpu_array_map.c index 9fdea8cd4c6f..0baf00463f35 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_percpu_array_map.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_percpu_array_map.c @@ -24,7 +24,7 @@ int dump_bpf_percpu_array_map(struct bpf_iter__bpf_map_elem *ctx) __u32 *key = ctx->key; void *pptr = ctx->value; __u32 step; - int i; + __u32 i; if (key == (void *)0 || pptr == (void *)0) return 0; diff --git a/tools/testing/selftests/bpf/progs/bpf_qdisc_fifo.c b/tools/testing/selftests/bpf/progs/bpf_qdisc_fifo.c index 1de2be3e370b..7a639dcb23a9 100644 --- a/tools/testing/selftests/bpf/progs/bpf_qdisc_fifo.c +++ b/tools/testing/selftests/bpf/progs/bpf_qdisc_fifo.c @@ -88,7 +88,7 @@ void BPF_PROG(bpf_fifo_reset, struct Qdisc *sch) { struct bpf_list_node *node; struct skb_node *skbn; - int i; + __u32 i; bpf_for(i, 0, sch->q.qlen) { struct sk_buff *skb = NULL; -- 2.51.1.dirty

2 weeks, 4 days

2
1
0 0

[PATCH bpf-next v2 0/2] bpf: Skip bounds adjustment for conditional jumps on same register

by KaFai Wan

This small patchset is about avoid verifier bug warning when conditional jumps on same register when the register holds a scalar with range. v2: - Enhance is_branch_taken() and is_scalar_branch_taken() to handle branch direction computation for same register. (Eduard and Alexei) - Update the selftest. v1: https://lore.kernel.org/bpf/20251022164457.1203756-1-kafai.wan@linux.dev/ --- KaFai Wan (2): bpf: Skip bounds adjustment for conditional jumps on same register selftests/bpf: Add test for BPF_JGT on same register kernel/bpf/verifier.c | 32 +++++++++++++++++++ .../selftests/bpf/progs/verifier_bounds.c | 18 +++++++++++ 2 files changed, 50 insertions(+) -- 2.43.0

2 weeks, 4 days

2
6
0 0

[PATCH] selftests: harness: Support KCOV.

by Kuniyuki Iwashima

While writing a selftest with kselftest_harness.h, I often want to check which paths are actually exercised. Let's support generating KCOV coverage data. We can specify the output directory via the KCOV_OUTPUT environment variable, and the number of instructions to collect via the KCOV_SLOTS environment variable. # KCOV_OUTPUT=$PWD/kcov KCOV_SLOTS=$((4096 * 2)) \ ./tools/testing/selftests/net/af_unix/scm_inq Both variables can also be specified as the make variable. # make -C tools/testing/selftests/ \ KCOV_OUTPUT=$PWD/kcov KCOV_SLOTS=$((4096 * 4)) \ kselftest_override_timeout=60 TARGETS=net/af_unix run_tests The coverage data can be simply decoded with addr2line: $ cat kcov/* | sort | uniq | addr2line -e vmlinux | grep unix net/unix/af_unix.c:1056 net/unix/af_unix.c:3138 net/unix/af_unix.c:3834 net/unix/af_unix.c:3838 net/unix/af_unix.c:311 (discriminator 2) ... or more nicely with a script embedded in vock [0]: $ cat kcov/* | sort | uniq > local.log $ python3 ~/kernel/tools/vock/report.py \ --kernel-src ./ --vmlinux ./vmlinux \ --mode local --local-log local.log --filter unix ... ------------------------------- Coverage Report -------------------------------- 📄 net/unix/af_unix.c (276 lines) ... 942 | static int unix_setsockopt(struct socket *sock, int level, int optname, 943 | sockptr_t optval, unsigned int optlen) 944 | { ... 961 | switch (optname) { 962 | case SO_INQ: 963 > if (sk->sk_type != SOCK_STREAM) 964 | return -EINVAL; 965 | 966 > if (val > 1 || val < 0) 967 | return -EINVAL; 968 | 969 > WRITE_ONCE(u->recvmsg_inq, val); 970 | break; Link: https://github.com/kzall0c/vock/blob/f3d97de9954f9df758c0ab287ca7e24e654288… #[0] Signed-off-by: Kuniyuki Iwashima <kuniyu(a)google.com> --- Documentation/dev-tools/kselftest.rst | 41 +++++++ tools/testing/selftests/Makefile | 14 ++- tools/testing/selftests/kselftest_harness.h | 128 +++++++++++++++++++- 3 files changed, 174 insertions(+), 9 deletions(-) diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst index 18c2da67fae42..5c2b92ac4a300 100644 --- a/Documentation/dev-tools/kselftest.rst +++ b/Documentation/dev-tools/kselftest.rst @@ -200,6 +200,47 @@ You can look at the TAP output to see if you ran into the timeout. Test runners which know a test must run under a specific time can then optionally treat these timeouts then as fatal. +KCOV for selftests +================== + +Selftests built with `kselftest_harness.h` natively support generating +KCOV coverage data. See :doc:`KCOV: code coverage for fuzzing </dev-tools/kcov>` +for prerequisites. + +You can specify the output directory with the `KCOV_OUTPUT` environment +variable. Additionally, you can specify the number of instructions to +collect with the `KCOV_SLOTS` environment variable :: + + # KCOV_OUTPUT=$PWD/kcov KCOV_SLOTS=$((4096 * 2)) \ + ./tools/testing/selftests/net/af_unix/scm_inq + +In the output directory, a coverage file is generated for each test +case in the selftest :: + + $ ls kcov/ + scm_inq.dgram.basic scm_inq.seqpacket.basic scm_inq.stream.basic + +The default value of `KCOV_SLOTS` is `4096`, and `KCOV_SLOTS` multiplied +by `sizeof(unsigned long)` must be multiple of `4096`, so the smallest +value is `512`. + +Both `KCOV_OUTPUT` and `KCOV_SLOTS` can be specified as the variables +on the `make` command line :: + + # make -C tools/testing/selftests/ \ + kselftest_override_timeout=60 \ + KCOV_OUTPUT=$PWD/kcov KCOV_SLOTS=$((4096 * 4)) \ + TARGETS=net/af_unix run_tests + +The collected data can be decoded with `addr2line` :: + + $ cat kcov/* | sort | uniq | addr2line -e vmlinux | grep unix + net/unix/af_unix.c:1056 + net/unix/af_unix.c:3138 + net/unix/af_unix.c:3834 + net/unix/af_unix.c:3838 + ... + Packaging selftests =================== diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index c46ebdb9b8ef7..40e70fb1a3478 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -218,12 +218,14 @@ all: done; exit $$ret; run_tests: all - @for TARGET in $(TARGETS); do \ - BUILD_TARGET=$$BUILD/$$TARGET; \ - $(MAKE) OUTPUT=$$BUILD_TARGET -C $$TARGET run_tests \ - SRC_PATH=$(shell readlink -e $$(pwd)) \ - OBJ_PATH=$(BUILD) \ - O=$(abs_objtree); \ + @for TARGET in $(TARGETS); do \ + BUILD_TARGET=$$BUILD/$$TARGET; \ + $(MAKE) OUTPUT=$$BUILD_TARGET \ + KCOV_OUTPUT=$(abspath $(KCOV_OUTPUT)) \ + -C $$TARGET run_tests \ + SRC_PATH=$(shell readlink -e $$(pwd)) \ + OBJ_PATH=$(BUILD) \ + O=$(abs_objtree); \ done; hotplug: diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h index 3f66e862e83eb..cba8020853b5d 100644 --- a/tools/testing/selftests/kselftest_harness.h +++ b/tools/testing/selftests/kselftest_harness.h @@ -56,6 +56,8 @@ #include <asm/types.h> #include <ctype.h> #include <errno.h> +#include <fcntl.h> +#include <linux/kcov.h> #include <linux/unistd.h> #include <poll.h> #include <stdbool.h> @@ -63,7 +65,9 @@ #include <stdio.h> #include <stdlib.h> #include <string.h> +#include <sys/ioctl.h> #include <sys/mman.h> +#include <sys/stat.h> #include <sys/types.h> #include <sys/wait.h> #include <unistd.h> @@ -401,7 +405,8 @@ const FIXTURE_VARIANT(fixture_name) *variant); \ static void wrapper_##fixture_name##_##test_name( \ struct __test_metadata *_metadata, \ - struct __fixture_variant_metadata *variant) \ + struct __fixture_variant_metadata *variant, \ + char *test_full_name) \ { \ /* fixture data is alloced, setup, and torn down per call. */ \ FIXTURE_DATA(fixture_name) self_private, *self = NULL; \ @@ -430,7 +435,9 @@ if (_metadata->exit_code) \ _exit(0); \ *_metadata->no_teardown = false; \ + enable_kcov(_metadata); \ fixture_name##_##test_name(_metadata, self, variant->data); \ + disable_kcov(_metadata, test_full_name); \ _metadata->teardown_fn(false, _metadata, self, variant->data); \ _exit(0); \ } else if (child < 0 || child != waitpid(child, &status, 0)) { \ @@ -470,6 +477,8 @@ object->teardown_fn = &wrapper_##fixture_name##_##test_name##_teardown; \ object->termsig = signal; \ object->timeout = tmout; \ + object->kcov_fd = -1; \ + object->kcov_slots = -1; \ _##fixture_name##_##test_name##_object = object; \ __register_test(object); \ } \ @@ -908,7 +917,8 @@ __register_fixture_variant(struct __fixture_metadata *f, struct __test_metadata { const char *name; void (*fn)(struct __test_metadata *, - struct __fixture_variant_metadata *); + struct __fixture_variant_metadata *, + char *test_name); pid_t pid; /* pid of test when being run */ struct __fixture_metadata *fixture; void (*teardown_fn)(bool in_parent, struct __test_metadata *_metadata, @@ -923,6 +933,10 @@ struct __test_metadata { const void *variant; struct __test_results *results; struct __test_metadata *prev, *next; + int kcov_fd; + int kcov_slots; + char *kcov_dir; + unsigned long *kcov_mem; }; static inline bool __test_passed(struct __test_metadata *metadata) @@ -1185,6 +1199,114 @@ static bool test_enabled(int argc, char **argv, return !has_positive; } +#define KCOV_SLOTS 4096 + +static void enable_kcov(struct __test_metadata *t) +{ + char *slots; + int err; + + t->kcov_dir = getenv("KCOV_OUTPUT"); + if (!t->kcov_dir || *t->kcov_dir == '\0') + return; + + slots = getenv("KCOV_SLOTS"); + if (slots && *slots != '\0') + sscanf(slots, "%d", &t->kcov_slots); + if (t->kcov_slots <= 0) + t->kcov_slots = KCOV_SLOTS; + + t->kcov_fd = open("/sys/kernel/debug/kcov", O_RDWR); + if (t->kcov_fd < 0) { + ksft_print_msg("ERROR OPENING KCOV FD\n"); + goto err; + } + + err = ioctl(t->kcov_fd, KCOV_INIT_TRACE, t->kcov_slots); + if (err) { + ksft_print_msg("ERROR INITIALISING KCOV\n"); + goto err; + } + + t->kcov_mem = mmap(NULL, sizeof(unsigned long) * t->kcov_slots, + PROT_READ | PROT_WRITE, MAP_SHARED, t->kcov_fd, 0); + if ((void *)t->kcov_mem == MAP_FAILED) { + ksft_print_msg("ERROR ALLOCATING MEMORY FOR KCOV\n"); + goto err; + } + + err = ioctl(t->kcov_fd, KCOV_ENABLE, KCOV_TRACE_PC); + if (err) { + ksft_print_msg("ERROR ENABLING KCOV\n"); + goto err; + } + + __atomic_store_n(&t->kcov_mem[0], 0, __ATOMIC_RELAXED); + return; +err: + t->exit_code = KSFT_FAIL; + _exit(KSFT_FAIL); +} + +static void disable_kcov(struct __test_metadata *t, char *test_name) +{ + int slots, err, dir, fd, i; + + if (t->kcov_fd == -1) + return; + + slots = __atomic_load_n(&t->kcov_mem[0], __ATOMIC_RELAXED); + if (slots == t->kcov_slots - 1) + ksft_print_msg("Set KCOV_SLOTS to a value greater than %d\n", t->kcov_slots); + + err = ioctl(t->kcov_fd, KCOV_DISABLE, 0); + if (err) { + ksft_print_msg("ERROR DISABLING KCOV\n"); + goto out; + } + + err = mkdir(t->kcov_dir, 0755); + if (err == -1 && errno != EEXIST) { + ksft_print_msg("ERROR CREATING '%s'\n", t->kcov_dir); + goto out; + } + err = 0; + + dir = open(t->kcov_dir, O_DIRECTORY); + if (dir < 0) { + ksft_print_msg("ERROR OPENING %s\n", t->kcov_dir); + err = dir; + goto out; + } + + fd = openat(dir, test_name, O_RDWR | O_CREAT | O_TRUNC); + + close(dir); + + if (fd == -1) { + ksft_print_msg("ERROR CREATING '%s' at '%s'\n", test_name, t->kcov_dir); + err = fd; + goto out; + } + + for (i = 0; i < slots; i++) { + char buf[64]; + int size; + + size = snprintf(buf, 64, "0x%lx\n", t->kcov_mem[i + 1]); + write(fd, buf, size); + } + +out: + munmap(t->kcov_mem, sizeof(t->kcov_mem[0]) * t->kcov_slots); + close(t->kcov_fd); + + if (err) { + t->exit_code = KSFT_FAIL; + _exit(KSFT_FAIL); + } +} + static void __run_test(struct __fixture_metadata *f, struct __fixture_variant_metadata *variant, struct __test_metadata *t) @@ -1216,7 +1338,7 @@ static void __run_test(struct __fixture_metadata *f, t->exit_code = KSFT_FAIL; } else if (child == 0) { setpgrp(); - t->fn(t, variant); + t->fn(t, variant, test_name); _exit(t->exit_code); } else { t->pid = child; -- 2.51.0.858.gf9c4a03a3a-goog

2 weeks, 5 days

2
3
0 0

[PATCH net-next v8 1/2] net/tls: support setting the maximum payload size

by Wilfred Mallawa

From: Wilfred Mallawa <wilfred.mallawa(a)wdc.com> During a handshake, an endpoint may specify a maximum record size limit. Currently, the kernel defaults to TLS_MAX_PAYLOAD_SIZE (16KB) for the maximum record size. Meaning that, the outgoing records from the kernel can exceed a lower size negotiated during the handshake. In such a case, the TLS endpoint must send a fatal "record_overflow" alert [1], and thus the record is discarded. Upcoming Western Digital NVMe-TCP hardware controllers implement TLS support. For these devices, supporting TLS record size negotiation is necessary because the maximum TLS record size supported by the controller is less than the default 16KB currently used by the kernel. Currently, there is no way to inform the kernel of such a limit. This patch adds support to a new setsockopt() option `TLS_TX_MAX_PAYLOAD_LEN` that allows for setting the maximum plaintext fragment size. Once set, outgoing records are no larger than the size specified. This option can be used to specify the record size limit. [1] https://www.rfc-editor.org/rfc/rfc8449 Signed-off-by: Wilfred Mallawa <wilfred.mallawa(a)wdc.com> --- V7 -> V8: - Fixup HTML doc indentation - Drop the getsockopt() change in V7 where ContentType was included in the max payload length --- Documentation/networking/tls.rst | 20 ++++++++++ include/net/tls.h | 3 ++ include/uapi/linux/tls.h | 2 + net/tls/tls_device.c | 2 +- net/tls/tls_main.c | 64 ++++++++++++++++++++++++++++++++ net/tls/tls_sw.c | 2 +- 6 files changed, 91 insertions(+), 2 deletions(-) diff --git a/Documentation/networking/tls.rst b/Documentation/networking/tls.rst index 36cc7afc2527..980c442d7161 100644 --- a/Documentation/networking/tls.rst +++ b/Documentation/networking/tls.rst @@ -280,6 +280,26 @@ If the record decrypted turns out to had been padded or is not a data record it will be decrypted again into a kernel buffer without zero copy. Such events are counted in the ``TlsDecryptRetry`` statistic. +TLS_TX_MAX_PAYLOAD_LEN +~~~~~~~~~~~~~~~~~~~~~~ + +Specifies the maximum size of the plaintext payload for transmitted TLS records. + +When this option is set, the kernel enforces the specified limit on all outgoing +TLS records. No plaintext fragment will exceed this size. This option can be used +to implement the TLS Record Size Limit extension [1]. + +* For TLS 1.2, the value corresponds directly to the record size limit. +* For TLS 1.3, the value should be set to record_size_limit - 1, since + the record size limit includes one additional byte for the ContentType + field. + +The valid range for this option is 64 to 16384 bytes for TLS 1.2, and 63 to +16384 bytes for TLS 1.3. The lower minimum for TLS 1.3 accounts for the +extra byte used by the ContentType field. + +[1] https://datatracker.ietf.org/doc/html/rfc8449 + Statistics ========== diff --git a/include/net/tls.h b/include/net/tls.h index 857340338b69..f2af113728aa 100644 --- a/include/net/tls.h +++ b/include/net/tls.h @@ -53,6 +53,8 @@ struct tls_rec; /* Maximum data size carried in a TLS record */ #define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14) +/* Minimum record size limit as per RFC8449 */ +#define TLS_MIN_RECORD_SIZE_LIM ((size_t)1 << 6) #define TLS_HEADER_SIZE 5 #define TLS_NONCE_OFFSET TLS_HEADER_SIZE @@ -226,6 +228,7 @@ struct tls_context { u8 rx_conf:3; u8 zerocopy_sendfile:1; u8 rx_no_pad:1; + u16 tx_max_payload_len; int (*push_pending_record)(struct sock *sk, int flags); void (*sk_write_space)(struct sock *sk); diff --git a/include/uapi/linux/tls.h b/include/uapi/linux/tls.h index b66a800389cc..b8b9c42f848c 100644 --- a/include/uapi/linux/tls.h +++ b/include/uapi/linux/tls.h @@ -41,6 +41,7 @@ #define TLS_RX 2 /* Set receive parameters */ #define TLS_TX_ZEROCOPY_RO 3 /* TX zerocopy (only sendfile now) */ #define TLS_RX_EXPECT_NO_PAD 4 /* Attempt opportunistic zero-copy */ +#define TLS_TX_MAX_PAYLOAD_LEN 5 /* Maximum plaintext size */ /* Supported versions */ #define TLS_VERSION_MINOR(ver) ((ver) & 0xFF) @@ -194,6 +195,7 @@ enum { TLS_INFO_RXCONF, TLS_INFO_ZC_RO_TX, TLS_INFO_RX_NO_PAD, + TLS_INFO_TX_MAX_PAYLOAD_LEN, __TLS_INFO_MAX, }; #define TLS_INFO_MAX (__TLS_INFO_MAX - 1) diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c index caa2b5d24622..4d29b390aed9 100644 --- a/net/tls/tls_device.c +++ b/net/tls/tls_device.c @@ -462,7 +462,7 @@ static int tls_push_data(struct sock *sk, /* TLS_HEADER_SIZE is not counted as part of the TLS record, and * we need to leave room for an authentication tag. */ - max_open_record_len = TLS_MAX_PAYLOAD_SIZE + + max_open_record_len = tls_ctx->tx_max_payload_len + prot->prepend_size; do { rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size); diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c index 39a2ab47fe72..56ce0bc8317b 100644 --- a/net/tls/tls_main.c +++ b/net/tls/tls_main.c @@ -541,6 +541,28 @@ static int do_tls_getsockopt_no_pad(struct sock *sk, char __user *optval, return 0; } +static int do_tls_getsockopt_tx_payload_len(struct sock *sk, char __user *optval, + int __user *optlen) +{ + struct tls_context *ctx = tls_get_ctx(sk); + u16 payload_len = ctx->tx_max_payload_len; + int len; + + if (get_user(len, optlen)) + return -EFAULT; + + if (len < sizeof(payload_len)) + return -EINVAL; + + if (put_user(sizeof(payload_len), optlen)) + return -EFAULT; + + if (copy_to_user(optval, &payload_len, sizeof(payload_len))) + return -EFAULT; + + return 0; +} + static int do_tls_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen) { @@ -560,6 +582,9 @@ static int do_tls_getsockopt(struct sock *sk, int optname, case TLS_RX_EXPECT_NO_PAD: rc = do_tls_getsockopt_no_pad(sk, optval, optlen); break; + case TLS_TX_MAX_PAYLOAD_LEN: + rc = do_tls_getsockopt_tx_payload_len(sk, optval, optlen); + break; default: rc = -ENOPROTOOPT; break; @@ -809,6 +834,32 @@ static int do_tls_setsockopt_no_pad(struct sock *sk, sockptr_t optval, return rc; } +static int do_tls_setsockopt_tx_payload_len(struct sock *sk, sockptr_t optval, + unsigned int optlen) +{ + struct tls_context *ctx = tls_get_ctx(sk); + struct tls_sw_context_tx *sw_ctx = tls_sw_ctx_tx(ctx); + u16 value; + bool tls_13 = ctx->prot_info.version == TLS_1_3_VERSION; + + if (sw_ctx && sw_ctx->open_rec) + return -EBUSY; + + if (sockptr_is_null(optval) || optlen != sizeof(value)) + return -EINVAL; + + if (copy_from_sockptr(&value, optval, sizeof(value))) + return -EFAULT; + + if (value < TLS_MIN_RECORD_SIZE_LIM - (tls_13 ? 1 : 0) || + value > TLS_MAX_PAYLOAD_SIZE) + return -EINVAL; + + ctx->tx_max_payload_len = value; + + return 0; +} + static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval, unsigned int optlen) { @@ -830,6 +881,11 @@ static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval, case TLS_RX_EXPECT_NO_PAD: rc = do_tls_setsockopt_no_pad(sk, optval, optlen); break; + case TLS_TX_MAX_PAYLOAD_LEN: + lock_sock(sk); + rc = do_tls_setsockopt_tx_payload_len(sk, optval, optlen); + release_sock(sk); + break; default: rc = -ENOPROTOOPT; break; @@ -1019,6 +1075,7 @@ static int tls_init(struct sock *sk) ctx->tx_conf = TLS_BASE; ctx->rx_conf = TLS_BASE; + ctx->tx_max_payload_len = TLS_MAX_PAYLOAD_SIZE; update_sk_prot(sk, ctx); out: write_unlock_bh(&sk->sk_callback_lock); @@ -1108,6 +1165,12 @@ static int tls_get_info(struct sock *sk, struct sk_buff *skb, bool net_admin) goto nla_failure; } + err = nla_put_u16(skb, TLS_INFO_TX_MAX_PAYLOAD_LEN, + ctx->tx_max_payload_len); + + if (err) + goto nla_failure; + rcu_read_unlock(); nla_nest_end(skb, start); return 0; @@ -1129,6 +1192,7 @@ static size_t tls_get_info_size(const struct sock *sk, bool net_admin) nla_total_size(sizeof(u16)) + /* TLS_INFO_TXCONF */ nla_total_size(0) + /* TLS_INFO_ZC_RO_TX */ nla_total_size(0) + /* TLS_INFO_RX_NO_PAD */ + nla_total_size(sizeof(u16)) + /* TLS_INFO_TX_MAX_PAYLOAD_LEN */ 0; return size; diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index d17135369980..9937d4c810f2 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1079,7 +1079,7 @@ static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg, orig_size = msg_pl->sg.size; full_record = false; try_to_copy = msg_data_left(msg); - record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size; + record_room = tls_ctx->tx_max_payload_len - msg_pl->sg.size; if (try_to_copy >= record_room) { try_to_copy = record_room; full_record = true; -- 2.51.0

2 weeks, 5 days

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[PATCH bpf-next v1] selftests/bpf: Guard addr_space_cast code with __BPF_FEATURE_ADDR_SPACE_CAST

by Jiayuan Chen

When compiling the BPF selftests with Clang versions that do not support the addr_space_cast builtin, the build fails with assembly errors in "verifier_ldsx.c" [1]. The root cause is that the inline assembly using addr_space_cast is being processed by a compiler that lacks this feature. To resolve this, wrap the affected code sections (specifically the arena_ldsx_* test functions) with #if defined(__BPF_FEATURE_ADDR_SPACE_CAST). This ensures the code is only compiled when the Clang supports the necessary feature, preventing build failures on older or incompatible compiler versions. This change maintains test coverage for systems with support while allowing the tests to build successfully in all environments. [1]: root:tools/testing/selftests/bpf$ make CLNG-BPF [test_progs] verifier_ldsx.bpf.o progs/verifier_ldsx.c:322:2: error: invalid operand for instruction 322 | "r1 = %[arena] ll;" | ^ <inline asm>:1:52: note: instantiated into assembly here 1 | r1 = arena ll;r0 = 0xdeadbeef;r0 = addr_space_cast(r0,... | ^ Fixes: f61654912404 ("selftests: bpf: Add tests for signed loads from arena") Signed-off-by: Jiayuan Chen <jiayuan.chen(a)linux.dev> --- tools/testing/selftests/bpf/progs/verifier_ldsx.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/verifier_ldsx.c b/tools/testing/selftests/bpf/progs/verifier_ldsx.c index c8494b682c31..cefa02e417d3 100644 --- a/tools/testing/selftests/bpf/progs/verifier_ldsx.c +++ b/tools/testing/selftests/bpf/progs/verifier_ldsx.c @@ -263,6 +263,7 @@ __naked void ldsx_ctx_8(void) : __clobber_all); } +#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) SEC("syscall") __description("Arena LDSX Disasm") __success @@ -425,6 +426,7 @@ __naked void arena_ldsx_s32(void *ctx) : __clobber_all ); } +#endif /* to retain debug info for BTF generation */ void kfunc_root(void) -- 2.43.0

2 weeks, 5 days

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[PATCH net v2 0/2] netconsole: Fix userdata race condition

by Gustavo Luiz Duarte

This series fixes a race condition in netconsole's userdata handling where concurrent message transmission could read partially updated userdata fields, resulting in corrupted netconsole output. The first patch adds a selftest that reproduces the race condition by continuously sending messages while rapidly changing userdata values, detecting any torn reads in the output. The second patch fixes the issue by ensuring update_userdata() holds the target_list_lock while updating both extradata_complete and userdata_length, preventing readers from seeing inconsistent state. This targets net tree as it fixes a bug introduced in commit df03f830d099 ("net: netconsole: cache userdata formatted string in netconsole_target"). Signed-off-by: Gustavo Luiz Duarte <gustavold(a)gmail.com> Changes in v2: - Added testcase to Makefile. - Reordered fix and testcase to avoid failure in CI. - testcase: delay cleanup until child process are killed, plus shellcheck fixes. - Link to v1: https://lore.kernel.org/all/20251020-netconsole-fix-race-v1-0-b775be30ee8a@… --- Gustavo Luiz Duarte (2): netconsole: Fix race condition in between reader and writer of userdata selftests: netconsole: Add race condition test for userdata corruption drivers/net/netconsole.c | 5 ++ tools/testing/selftests/drivers/net/Makefile | 1 + .../selftests/drivers/net/netcons_race_userdata.sh | 87 ++++++++++++++++++++++ 3 files changed, 93 insertions(+) --- base-commit: d63f0391d6c7b75e1a847e1a26349fa8cad0004d change-id: 20251020-netconsole-fix-race-f465f37b57ea Best regards, -- Gustavo Duarte <gustavold(a)meta.com>

2 weeks, 5 days

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[PATCH bpf-next 0/2] bpf: Fix tnum_overlap to check for zero mask first

by KaFai Wan

This small patchset is about avoid verifier bug warning when tnum_overlap() is called with zero mask. --- KaFai Wan (2): bpf: Fix tnum_overlap to check for zero mask first selftests/bpf: Range analysis test case for JEQ kernel/bpf/tnum.c | 2 ++ .../selftests/bpf/progs/verifier_bounds.c | 23 +++++++++++++++++++ 2 files changed, 25 insertions(+) -- 2.43.0

2 weeks, 5 days

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[PATCH v2] selftest: net: fix variable sized type issue not at the end of a struct

by Ankit Khushwaha

Some network selftests defined variable-sized types variable at the middle of struct causing -Wgnu-variable-sized-type-not-at-end warning. warning: timestamping.c:285:18: warning: field 'cm' with variable sized type 'struct cmsghdr' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] 285 | struct cmsghdr cm; | ^ ipsec.c:835:5: warning: field 'u' with variable sized type 'union (unnamed union at ipsec.c:831:3)' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] 835 | } u; | ^ This patch move these field at the end of struct to fix these warnings. Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux(a)gmail.com> --- Changelog: v2: https://lore.kernel.org/linux-kselftest/20251027050856.30270-1-ankitkhushwa… - fixed typos in the commit msg. --- tools/testing/selftests/net/ipsec.c | 2 +- tools/testing/selftests/net/timestamping.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/net/ipsec.c b/tools/testing/selftests/net/ipsec.c index 0ccf484b1d9d..36083c8f884f 100644 --- a/tools/testing/selftests/net/ipsec.c +++ b/tools/testing/selftests/net/ipsec.c @@ -828,12 +828,12 @@ static int xfrm_state_pack_algo(struct nlmsghdr *nh, size_t req_sz, struct xfrm_desc *desc) { struct { + char buf[XFRM_ALGO_KEY_BUF_SIZE]; union { struct xfrm_algo alg; struct xfrm_algo_aead aead; struct xfrm_algo_auth auth; } u; - char buf[XFRM_ALGO_KEY_BUF_SIZE]; } alg = {}; size_t alen, elen, clen, aelen; unsigned short type; diff --git a/tools/testing/selftests/net/timestamping.c b/tools/testing/selftests/net/timestamping.c index 044bc0e9ed81..ad2be2143698 100644 --- a/tools/testing/selftests/net/timestamping.c +++ b/tools/testing/selftests/net/timestamping.c @@ -282,8 +282,8 @@ static void recvpacket(int sock, int recvmsg_flags, struct iovec entry; struct sockaddr_in from_addr; struct { - struct cmsghdr cm; char control[512]; + struct cmsghdr cm; } control; int res; -- 2.51.0

2 weeks, 5 days

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