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[PATCH v4] uaccess_testing: Testing of capability enforcement in uaccess

by Akram Ahmad

Add tests for capability enforcement via the standard copy routines (copy_{to, from}_user, {get, put}_user), futex operations and the explicit uaccess checks used in iov_iter via readv and writev. Signed-off-by: Akram Ahmad <Akram.Ahmad(a)arm.com> --- Hi everyone, This is v4 of the uaccess kselftest patch and introduces the following: - Simplification of the futex test to only use one futex - Move FUTEX_WAKE_OP description to futex test - Various minor corrections V3 introduced the following changes: - Corrections to function prototypes to remove void * in favour of the actual struct pointer types and other minor corrections. - Correction to the futex test, which now tests for a correctly enforced uaccess routine when used in an atomic operation. - Reintroduction of the out-of-bounds checking in tests. V2 introduced the following changes: - More concise formatting changes - Corrections to various mistakes in tests - Addition of a strlen_user() test - Fixed futex test The review branch can be found at: https://git.morello-project.org/arkamnite/linux/-/commits/morello/uaccess_v4 The related issue can also be found at: https://git.morello-project.org/morello/kernel/linux/-/issues/58 Many thanks, Akram --- .../testing/selftests/arm64/morello/Makefile | 2 +- .../testing/selftests/arm64/morello/uaccess.c | 262 ++++++++++++++++++ 2 files changed, 263 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/morello/uaccess.c diff --git a/tools/testing/selftests/arm64/morello/Makefile b/tools/testing/selftests/arm64/morello/Makefile index ecfa6fc5e989..7b794d3e436c 100644 --- a/tools/testing/selftests/arm64/morello/Makefile +++ b/tools/testing/selftests/arm64/morello/Makefile @@ -17,7 +17,7 @@ CFLAGS += $(CLANG_FLAGS) $(CFLAGS_PURECAP) $(CFLAGS_COMMON) LDFLAGS += $(CLANG_LDFLAGS) $(CLANG_FLAGS) -nostdlib -static SRCS := $(wildcard *.c) $(wildcard *.S) -PROGS := bootstrap clone exit mmap read_write sched signal +PROGS := bootstrap clone exit mmap read_write sched signal uaccess DEPS := $(wildcard *.h) # these are the final executables diff --git a/tools/testing/selftests/arm64/morello/uaccess.c b/tools/testing/selftests/arm64/morello/uaccess.c new file mode 100644 index 000000000000..ee2847472bc2 --- /dev/null +++ b/tools/testing/selftests/arm64/morello/uaccess.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2023 Arm Limited + +#include <stdint.h> +#include <stddef.h> +#include <stdbool.h> + +#include <asm/fcntl.h> +#include <asm-generic/errno-base.h> +#include <cheriintrin.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/futex.h> +#include <linux/mman.h> +#include <linux/signal.h> +#include <linux/sysinfo.h> +#include <linux/socket.h> +#include <linux/time.h> +#include <linux/uio.h> + +#include "freestanding.h" + +#define MSG_LEN 16 + +static const char file[] = "/my_file.txt"; + +static inline int fsopen(const char *string) +{ + return syscall(__NR_fsopen, string); +} + + +static inline int futex_wake_op(uint32_t *uaddr, uint32_t *uaddr2, uint32_t val3) +{ + return syscall(__NR_futex, uaddr, FUTEX_WAKE_OP, 1, 1, + uaddr2, val3); +} + +typedef unsigned short sa_family_t; + +struct sockaddr { + sa_family_t sa_family; + char sa_data[14]; +}; + +static int getsockname(int socket, struct sockaddr *sockaddr, int *socklen) +{ + return syscall(__NR_getsockname, socket, sockaddr, socklen); +} + +static int open_file(void) +{ + return syscall(__NR_openat, 0, file, O_RDWR | O_CREAT, 0666); +} + +static inline int readv(int fd, struct iovec *iov, int iovcnt) +{ + return syscall(__NR_readv, fd, iov, iovcnt); +} + +static inline int writev(int fd, struct iovec *iov, int iovcnt) +{ + return syscall(__NR_writev, fd, iov, iovcnt); +} + +static inline int sigaction(int sig, struct sigaction *old, struct sigaction *new) +{ + return syscall(__NR_rt_sigaction, sig, old, new, sizeof(sigset_t)); +} + +static inline int sysinfo(struct sysinfo *ptr) +{ + return syscall(__NR_sysinfo, ptr); +} + +TEST(test_copy_to_user) +{ + struct sysinfo my_sysinfo; + + ASSERT_EQ(sysinfo(&my_sysinfo), 0); + + ASSERT_EQ(sysinfo(&my_sysinfo + sizeof(struct sysinfo)), -EFAULT); + + ASSERT_EQ(sysinfo(cheri_tag_clear(&my_sysinfo)), -EFAULT); + + ASSERT_EQ(sysinfo(cheri_perms_and(&my_sysinfo, 0)), -EFAULT); +} + +/* + * sigaction() tests both copy_to_user and copy_from_user by copying + * into and from a pointer to struct sigaction. The resulting action + * in this case is a no-op, but this does not affect the validity of + * the test. sigaction attempts to copy the new action from user space + * and the old action to user space, if the arguments is valid in either + * case. + */ +TEST(test_copy_user) +{ + struct sigaction act; + + ASSERT_EQ(sigaction(SIGSEGV, NULL, &act), 0); + ASSERT_EQ(sigaction(SIGSEGV, &act, NULL), 0); + + ASSERT_EQ(sigaction(SIGSEGV, NULL, &act + sizeof(struct sigaction)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, &act + sizeof(struct sigaction), NULL), -EFAULT); + + ASSERT_EQ(sigaction(SIGSEGV, NULL, cheri_tag_clear(&act)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, cheri_tag_clear(&act), NULL), -EFAULT); + + ASSERT_EQ(sigaction(SIGSEGV, NULL, cheri_perms_and(&act, 0)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, cheri_perms_and(&act, 0), NULL), -EFAULT); +} + +/* + * getsockname(2) uses both get_user and put_user to copy the addrlen argument + * from and to user space respectively. getsockname(2) calls move_addr_to_user + * to copy an address to user space. move_addr_to_user also uses copy_to_user; + * if copy_to_user is successful, but either of get_user or put_user fail then + * getsockname(2) will return -EFAULT appropriately. + */ +TEST(test_get_put_user) +{ + struct sockaddr sa; + int sa_len = sizeof(sa); + int my_socket; + + // socket(AF_INET, SOCK_STREAM, 0) + my_socket = syscall(__NR_socket, 2, 1, 0); + + // The socket must be successfully opened before proceeding. + ASSERT_GE(my_socket, 0); + + ASSERT_EQ(getsockname(my_socket, &sa, &sa_len), 0); + ASSERT_EQ(getsockname(my_socket, &sa, &sa_len + sizeof(struct sockaddr)), -EFAULT); + ASSERT_EQ(getsockname(my_socket, &sa, cheri_tag_clear(&sa_len)), -EFAULT); + ASSERT_EQ(getsockname(my_socket, &sa, cheri_perms_and(&sa_len, 0)), -EFAULT); + close(my_socket); +} + +/* + * The FUTEX_WAKE_OP operation in the futex(2) syscall is used to handle more + * than one futex at the same time. This is an atomic operation that attempts + * to read, modify and write a value at a second uaddr (uaddr2) and also wake + * up waiters on the futex words at uaddr1 and uaddr2. uaddr1 and uaddr2 are + * provided via capabilities, and so this futex tests the case of an atomic + * uaccess operation. + * + * When using FUTEX_WAKE_OP, val3 is an encoding of both the operation as + * well as the comparison to be performed on the futex word at uaddr2. If val3 + * is set to 0, this represents an operation of FUTEX_OP_SET and a comparison + * FUTEX_OP_CMP_EQ, where both oparg and comparg are 0. + */ +TEST(test_futex) +{ + static struct futex_waitv waitv; + uint32_t futex = 0; + + waitv.uaddr = (uintptr_t)&futex; + waitv.flags = FUTEX_32 | FUTEX_PRIVATE_FLAG; + waitv.val = futex; + waitv.__reserved = 0; + + ASSERT_GE(futex_wake_op(&futex, &futex, 0), 0); + ASSERT_EQ(futex_wake_op(&futex, &futex + sizeof(uint32_t), 0), -EFAULT); + ASSERT_EQ(futex_wake_op(&futex, cheri_tag_clear(&futex), 0), -EFAULT); + ASSERT_EQ(futex_wake_op(&futex, cheri_perms_and(&futex, 0), 0), + -EFAULT); +} + +/* + * Test explicit accesses used in iov_iter via readv and writev. Both + * syscalls use explicit checking on the iov_base field of struct iovec, + * so the metadata of the capability provided for iov_base is modified as + * per the needs of each individual test. + */ +TEST(test_explicit_iov_iter) +{ + char buf0[2]; + char buf1[4]; + char buf2[6]; + const char *write_buf0 = "Hello I am the first char buffer!\n"; + const char *write_buf1 = "Hello, I am the second char buffer.\n"; + const char *write_buf2 = "Hello, I am the third and final char buffer.\n"; + struct iovec iov[3]; + int iovcnt; + int fd; + + fd = open_file(); + ASSERT_NE(fd, -1); + + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + ASSERT_GE(readv(fd, iov, iovcnt), 0); + + iov[0].iov_base = buf0 + sizeof(iov) * 100; + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = cheri_tag_clear(buf0); + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = cheri_perms_and(buf0, 0); + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = (void *)write_buf0; + iov[0].iov_len = strlen(write_buf0); + iov[1].iov_base = (void *)write_buf1; + iov[1].iov_len = strlen(write_buf1); + iov[2].iov_base = (void *)write_buf2; + iov[2].iov_len = strlen(write_buf2); + + ASSERT_GE(writev(fd, iov, iovcnt), 0); + + iov[0].iov_base = (void *)write_buf0 + sizeof(iov) * 100; + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = (void *)cheri_tag_clear(write_buf0); + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = (void *)cheri_perms_and(write_buf0, 0); + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT); + + close(fd); +} + +/* + * strlen_user() explicitly inspects an input capability, the behaviour + * of which must also be verified within these tests. The fsopen() syscall + * makes use of strlen_user() by duplicating a string (representing the name + * of a filesystem) with the strndup_user() function. strlen_user() can + * therefore be tested with a call to fsopen(). + */ +TEST(test_strlen_user) +{ + const char *fsname = "my_nonexistent_filesystem"; + + // strndup_user() will still be called, so fsopen() fails after this. + ASSERT_EQ(fsopen(fsname), -ENODEV); + + ASSERT_EQ(fsopen(fsname + strlen(fsname) * 10), -EFAULT); + + ASSERT_EQ(fsopen(cheri_tag_clear(fsname)), -EFAULT); + + ASSERT_EQ(fsopen(cheri_perms_and(fsname, 0)), -EFAULT); +} + +int main(void) +{ + test_copy_to_user(); + test_copy_user(); + test_get_put_user(); + test_futex(); + test_explicit_iov_iter(); + test_strlen_user(); + return 0; +} -- 2.34.1

1 year, 9 months

2
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[PATCH v3] uaccess_testing: Testing of capability enforcement in uaccess

by Akram Ahmad

Add tests for capability enforcement via the standard copy routines (copy_{to, from}_user, {get, put}_user), futex operations and the explicit uaccess checks used in iov_iter via readv and writev. Signed-off-by: Akram Ahmad <Akram.Ahmad(a)arm.com> --- Hi everyone, This is v3 of the uaccess kselftest patch. The main changes from V2 to V3 are: - Corrections to function prototypes to remove void * in favour of the actual struct pointer types and other minor corrections. - Correction to the futex test, which now tests for a correctly enforced uaccess routine when used in an atomic operation. - Reintroduction of the out-of-bounds checking in tests. V2 introduced the following changes: - More concise formatting changes - Corrections to various mistakes in tests - Addition of a strlen_user() test - Fixed futex test The review branch can be found at: https://git.morello-project.org/arkamnite/linux/-/commits/morello%2Fuaccess… The related issue can also be found at: https://git.morello-project.org/morello/kernel/linux/-/issues/58 Many thanks, Akram --- .../testing/selftests/arm64/morello/Makefile | 2 +- .../testing/selftests/arm64/morello/uaccess.c | 271 ++++++++++++++++++ 2 files changed, 272 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/morello/uaccess.c diff --git a/tools/testing/selftests/arm64/morello/Makefile b/tools/testing/selftests/arm64/morello/Makefile index ecfa6fc5e989..7b794d3e436c 100644 --- a/tools/testing/selftests/arm64/morello/Makefile +++ b/tools/testing/selftests/arm64/morello/Makefile @@ -17,7 +17,7 @@ CFLAGS += $(CLANG_FLAGS) $(CFLAGS_PURECAP) $(CFLAGS_COMMON) LDFLAGS += $(CLANG_LDFLAGS) $(CLANG_FLAGS) -nostdlib -static SRCS := $(wildcard *.c) $(wildcard *.S) -PROGS := bootstrap clone exit mmap read_write sched signal +PROGS := bootstrap clone exit mmap read_write sched signal uaccess DEPS := $(wildcard *.h) # these are the final executables diff --git a/tools/testing/selftests/arm64/morello/uaccess.c b/tools/testing/selftests/arm64/morello/uaccess.c new file mode 100644 index 000000000000..d1624f61adcd --- /dev/null +++ b/tools/testing/selftests/arm64/morello/uaccess.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2023 Arm Limited + +#include <stdint.h> +#include <stddef.h> +#include <stdbool.h> + +#include <asm/fcntl.h> +#include <asm-generic/errno-base.h> +#include <cheriintrin.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/futex.h> +#include <linux/mman.h> +#include <linux/signal.h> +#include <linux/sysinfo.h> +#include <linux/socket.h> +#include <linux/time.h> +#include <linux/uio.h> + +#include "freestanding.h" + +#define MSG_LEN 16 +#define NR_FUTEXES 5 + +static const char file[] = "/my_file.txt"; + +static inline int fsopen(const char *string) +{ + return syscall(__NR_fsopen, string); +} + +/* + * FUTEX_WAKE_OP is an operation used to handle more than one futex at the same + * time. When using FUTEX_WAKE_OP, val3 is an encoding of both the operation as + * well as the comparison to be performed on the futex word at uaddr2. If val3 + * is set to 0, this represents an operation of FUTEX_OP_SET and a comparison + * FUTEX_OP_CMP_EQ, where both oparg and comparg are 0. + */ +static inline int futex_wake(uint32_t *uaddr, uint32_t *uaddr2, uint32_t val3, + const struct timespec *timeout) +{ + return syscall(__NR_futex, uaddr, FUTEX_WAKE_OP, NR_FUTEXES, timeout, + uaddr2, val3); +} + +typedef unsigned short sa_family_t; + +struct sockaddr { + sa_family_t sa_family; + char sa_data[14]; +}; + +static int getsockname(int socket, struct sockaddr *sockaddr, int *socklen) +{ + return syscall(__NR_getsockname, socket, sockaddr, socklen); +} + +static int open_file(void) +{ + return syscall(__NR_openat, 0, file, O_RDWR | O_CREAT, 0666); +} + +static inline int readv(int fd, struct iovec *iov, int iovcnt) +{ + return syscall(__NR_readv, fd, iov, iovcnt); +} + +static inline int writev(int fd, struct iovec *iov, int iovcnt) +{ + return syscall(__NR_writev, fd, iov, iovcnt); +} + +static inline int sigaction(int sig, struct sigaction *old, struct sigaction *new) +{ + return syscall(__NR_rt_sigaction, sig, old, new, sizeof(sigset_t)); +} + +static inline int sysinfo(struct sysinfo *ptr) +{ + return syscall(__NR_sysinfo, ptr); +} + +TEST(test_copy_to_user) +{ + struct sysinfo my_sysinfo; + + ASSERT_EQ(sysinfo(&my_sysinfo), 0); + + ASSERT_EQ(sysinfo(&my_sysinfo + sizeof(struct sysinfo) * 100), -EFAULT); + + ASSERT_EQ(sysinfo(cheri_tag_clear(&my_sysinfo)), -EFAULT); + + ASSERT_EQ(sysinfo(cheri_perms_and(&my_sysinfo, 0)), -EFAULT); +} + +/* + * sigaction() tests both copy_to_user and copy_from_user by copying + * into and from a pointer to struct sigaction. The resulting action + * in this case is a no-op, but this does not affect the validity of + * the test. sigaction attempts to copy the new action from user space + * and the old action to user space, if the arguments is valid in either + * case. + */ +TEST(test_copy_user) +{ + struct sigaction act; + + ASSERT_EQ(sigaction(SIGSEGV, NULL, &act), 0); + ASSERT_EQ(sigaction(SIGSEGV, &act, NULL), 0); + + ASSERT_EQ(sigaction(SIGSEGV, NULL, &act + sizeof(struct sigaction) * 100), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, &act + sizeof(struct sigaction) * 100, NULL), -EFAULT); + + ASSERT_EQ(sigaction(SIGSEGV, NULL, cheri_tag_clear(&act)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, cheri_tag_clear(&act), NULL), -EFAULT); + + ASSERT_EQ(sigaction(SIGSEGV, NULL, cheri_perms_and(&act, 0)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, cheri_perms_and(&act, 0), NULL), -EFAULT); +} + +/* + * getsockname(2) uses both get_user and put_user to copy the addrlen argument + * from and to user space respectively. getsockname(2) calls move_addr_to_user + * to copy an address to user space. move_addr_to_user also uses copy_to_user; + * if copy_to_user is successful, but either of get_user or put_user fail then + * getsockname(2) will return -EFAULT appropriately. + */ +TEST(test_get_put_user) +{ + struct sockaddr sa; + int sa_len = sizeof(sa); + int my_socket; + + // socket(AF_INET, SOCK_STREAM, 0) + my_socket = syscall(__NR_socket, 2, 1, 0); + + // The socket must be successfully opened before proceeding. + ASSERT_GE(my_socket, 0); + + ASSERT_EQ(getsockname(my_socket, &sa, &sa_len), 0) + ASSERT_EQ(getsockname(my_socket, &sa, &sa_len + sizeof(struct sockaddr) * 100), -EFAULT) + ASSERT_EQ(getsockname(my_socket, &sa, cheri_tag_clear(&sa_len)), -EFAULT) + ASSERT_EQ(getsockname(my_socket, &sa, cheri_perms_and(&sa_len, 0)), -EFAULT) + close(my_socket); +} + +/* + * The FUTEX_WAKE_OP operation in the futex(2) syscall is used to handle more + * than one futex at the same time. This is an atomic operation that attempts + * to read, modify and write a value at a second uaddr (uaddr2) and also wake + * up waiters on the futex words at uaddr1 and uaddr2. uaddr1 and uaddr2 are + * provided via capabilities, and so this futex tests the case of an atomic + * uaccess operation. + */ +TEST(test_futex) +{ + static struct futex_waitv waitv[NR_FUTEXES]; + uint32_t futexes[NR_FUTEXES] = {0}; + struct timespec to = {.tv_sec = 0, .tv_nsec = 500000000}; + + for (int i = 0; i < NR_FUTEXES; i++) { + waitv[i].uaddr = (uintptr_t)&futexes[i]; + waitv[i].flags = FUTEX_32 | FUTEX_PRIVATE_FLAG; + waitv[i].val = futexes[i]; + waitv[i].__reserved = 0; + } + + ASSERT_GE(futex_wake(&futexes[0], &futexes[0], 0, &to), 0); + ASSERT_EQ(futex_wake(&futexes[0], + &futexes[0] + sizeof(uint32_t) * NR_FUTEXES, 0, + &to), + -EFAULT); + ASSERT_EQ(futex_wake(&futexes[0], cheri_tag_clear(&futexes[0]), 0, &to), + -EFAULT); + ASSERT_EQ(futex_wake(&futexes[0], cheri_perms_and(&futexes[0], 0), 0, + &to), + -EFAULT); +} + +/* + * Test explicit accesses used in iov_iter via readv and writev. Both + * syscalls use explicit checking on the iov_base field of struct iovec, + * so the metadata of the capability provided for iov_base is modified as + * per the needs of each individual test. + */ +TEST(test_explicit_iov_iter) +{ + char buf0[2]; + char buf1[4]; + char buf2[6]; + char *write_buf0 = "Hello I am the first char buffer!\n"; + char *write_buf1 = "Hello, I am the second char buffer.\n"; + char *write_buf2 = "Hello, I am the third and final char buffer.\n"; + struct iovec iov[3]; + int iovcnt; + static int fd; + + fd = open_file(); + ASSERT_NE(fd, -1); + + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + ASSERT_GE(readv(fd, iov, iovcnt), 0); + + iov[0].iov_base = buf0 + sizeof(iov) * 100; + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = cheri_tag_clear(buf0); + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = cheri_perms_and(buf0, 0); + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = write_buf0; + iov[0].iov_len = strlen(write_buf0); + iov[1].iov_base = write_buf1; + iov[1].iov_len = strlen(write_buf1); + iov[2].iov_base = write_buf2; + iov[2].iov_len = strlen(write_buf2); + + ASSERT_GE(writev(fd, iov, iovcnt), 0); + + iov[0].iov_base = write_buf0 + sizeof(iov) * 100; + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = cheri_tag_clear(write_buf0); + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT); + + iov[0].iov_base = cheri_perms_and(write_buf0, 0); + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT); +} + +/* + * strlen_user() explicitly inspects an input capability, the behaviour + * of which must also be verified within these tests. The fsopen() syscall + * makes use of strlen_user() by duplicating a string (representing the name + * of a filesystem) with the strndup_user() function. strlen_user() can + * therefore be tested with a call to fsopen(). + */ +TEST(test_strlen_user) +{ + const char *fsname = "my_nonexistent_filesystem"; + + // strndup_user() will still be called, so fsopen() fails after this. + ASSERT_EQ(fsopen(fsname), -ENODEV); + + ASSERT_EQ(fsopen(fsname + strlen(fsname) * 10), -EFAULT); + + ASSERT_EQ(fsopen(cheri_tag_clear(fsname)), -EFAULT); + + ASSERT_EQ(fsopen(cheri_perms_and(fsname, 0)), -EFAULT); +} + +int main(void) +{ + test_copy_to_user(); + test_copy_user(); + test_get_put_user(); + test_futex(); + test_explicit_iov_iter(); + test_strlen_user(); + return 0; +} -- 2.34.1

1 year, 9 months

2
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[PATCH 00/12] Switch to capability-based uaccess

by Kevin Brodsky

Hi, This series switches all uaccess routines to operate directly on the user-provided capability pointer in PCuABI, instead of making the access via the extracted 64-bit address. This means that all forms of uaccess now enforce the capability metadata, through the use of capability-based loads and stores, and will fail with -EFAULT following a failed (hardware) capability check. The impacted routines are: - *get_user* (including get_user_ptr) - *put_user* (including put_user_ptr) - *copy_from_user* (including copy_from_user_with_ptr) - *copy_to_user* (including copy_to_user_with_ptr) (Note that futex operations are already checked thanks to Luca's work [1].) Enabling capability checks in uaccess exposed a variety of issues, both in the kernel and in userspace. This series addresses the fallout in the kernel before making the switch: - Patch 1-3 overhaul strnlen_user() to prevent it from reading beyond the bounds of the user pointer, while leaving its implementation unchanged in !PCuABI. - Patch 4-6 fixes various capability propagation issues (surprisingly few of those!). - Patch 7 fixes a bug in a Morello kselftest, detected through capability checking in copy_from_user(). Finally, the switch to capability-based accesses is made: - Patch 8-10 switch {get,put}_user and variants. - Patch 11-12 switch copy_{from,to}_user and variants. After this series, the Morello kselftests and Musl tests still pass, and so do the liburing tests, however the LTP syscalls suite doesn't because of various issues in LTP itself. I have addressed a number of them upstream [2] (series already merged), and will post the remaining fixes to linux-morello-ltp. Because this precise uaccess checking cannot be achieved with most existing sanitisers or hardware memory safety mechanisms, further bugs are likely to be identified in low-level libraries and test suites running in purecap (I have spotted a couple in the Bionic tests). Issue: https://git.morello-project.org/morello/kernel/linux/-/issues/5 Review branch: https://git.morello-project.org/kbrodsky-arm/linux/-/commits/morello/checke… Cheers, Kevin [1] https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [2] https://lore.kernel.org/ltp/20231023135647.2157030-1-kevin.brodsky@arm.com/ Kevin Brodsky (12): linux/user_ptr.h: Introduce user_ptr_{base,limit} lib: Refactor do_strnlen_user() lib: Make strnlen_user() PCuABI-friendly block: Eliminate invalid user pointer casts tty: Convert another ioctl helper to take arg as user_uintptr_t seccomp: Preserve pointers when reading sock_fprog from userspace kselftests/arm64: morello: Fix message size in mmap test arm64: morello: Implement user capability accessors inline arm64: uaccess: Move macros from futex.h to uaccess.h arm64: uaccess: Switch to capability-based {get,put}_user in PCuABI arm64: lib: Simplify copy_*_user register allocation arm64: lib: Switch to capability-based copy_*_user in PCuABI Documentation/core-api/user_ptr.rst | 13 ++ arch/arm64/include/asm/assembler.h | 8 + arch/arm64/include/asm/futex.h | 20 +-- arch/arm64/include/asm/gpr-num.h | 6 +- arch/arm64/include/asm/morello.h | 4 - arch/arm64/include/asm/uaccess.h | 49 +++++- arch/arm64/lib/copy_from_user.S | 33 +++- arch/arm64/lib/copy_template.S | 14 +- arch/arm64/lib/copy_to_user.S | 17 +- arch/arm64/lib/morello.S | 23 --- block/blk-zoned.c | 6 +- block/ioctl.c | 22 +-- drivers/tty/tty_ioctl.c | 2 +- include/linux/blkdev.h | 8 +- include/linux/tty.h | 2 +- include/linux/user_ptr.h | 44 +++++ kernel/seccomp.c | 2 +- lib/strnlen_user.c | 163 +++++++++++++++---- tools/testing/selftests/arm64/morello/mmap.c | 2 +- 19 files changed, 319 insertions(+), 119 deletions(-) -- 2.38.1

1 year, 9 months

3
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[PATCH v2] uaccess_testing: Testing of capability enforcement in uaccess

by Akram Ahmad

Add tests for capability enforcement via the standard copy routines (copy_{to, from}_user, {get, put}_user), futex operations and the explicit uaccess checks used in iov_iter via readv and writev. Signed-off-by: Akram Ahmad <Akram.Ahmad(a)arm.com> --- Hi everyone, This is V2 of the uaccess kselftest patch. The main changes are: - More concise formatting changes - Corrections to various mistakes in tests - Addition of a strlen_user() test case One of the most important fixes is the fixed futex test. It turns out that whilst optimisation was causing some varying results, the overall problem was to do with a mistake in the use of the syscall. I've decided to allow the syscall to timeout in the case of a valid input capability, as I feel this tests the explicit uaccess check sufficiently, but I am not sure if this is the ideal method. Many thanks, Akram --- .../testing/selftests/arm64/morello/Makefile | 2 +- .../testing/selftests/arm64/morello/uaccess.c | 294 ++++++++++++++++++ 2 files changed, 295 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/morello/uaccess.c diff --git a/tools/testing/selftests/arm64/morello/Makefile b/tools/testing/selftests/arm64/morello/Makefile index ecfa6fc5e989..7b794d3e436c 100644 --- a/tools/testing/selftests/arm64/morello/Makefile +++ b/tools/testing/selftests/arm64/morello/Makefile @@ -17,7 +17,7 @@ CFLAGS += $(CLANG_FLAGS) $(CFLAGS_PURECAP) $(CFLAGS_COMMON) LDFLAGS += $(CLANG_LDFLAGS) $(CLANG_FLAGS) -nostdlib -static SRCS := $(wildcard *.c) $(wildcard *.S) -PROGS := bootstrap clone exit mmap read_write sched signal +PROGS := bootstrap clone exit mmap read_write sched signal uaccess DEPS := $(wildcard *.h) # these are the final executables diff --git a/tools/testing/selftests/arm64/morello/uaccess.c b/tools/testing/selftests/arm64/morello/uaccess.c new file mode 100644 index 000000000000..e3c935df948a --- /dev/null +++ b/tools/testing/selftests/arm64/morello/uaccess.c @@ -0,0 +1,294 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2023 Arm Limited + +#include <stdint.h> +#include <stddef.h> +#include <stdbool.h> + +#include <asm/fcntl.h> +#include <asm-generic/errno-base.h> +#include <cheriintrin.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/futex.h> +#include <linux/mman.h> +#include <linux/signal.h> +#include <linux/sysinfo.h> +#include <linux/socket.h> +#include <linux/time.h> +#include <linux/uio.h> + +#include "freestanding.h" + +#define MSG_LEN 16 +#define NR_FUTEXES 1 + +static struct futex_waitv waitv[NR_FUTEXES]; +uint32_t futexes[NR_FUTEXES] = {1}; + +static const char file[] = "/my_file.txt"; +static int fd; + +static inline int fsopen(void *string) +{ + return syscall(__NR_fsopen, string); +} + +static inline int futex_waitv(struct futex_waitv *waiters, unsigned long nr_waiters, + unsigned long flags, struct timespec *timo, clockid_t clockid) +{ + return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, timo, clockid); +} + +static int getsockname(int socket, void *sockaddr, int *socklen) +{ + return syscall(__NR_getsockname, socket, sockaddr, socklen); +} + +static int open_file(void) +{ + return syscall(__NR_openat, 0, file, O_RDWR | O_CREAT, 0666); +} + +static inline int readv(int fd, struct iovec *iov, int iovcnt) +{ + return syscall(__NR_readv, fd, iov, iovcnt); +} + +static inline int writev(int fd, struct iovec *iov, int iovcnt) +{ + return syscall(__NR_writev, fd, iov, iovcnt); +} + +static inline int sigaction(int sig, void *old, void *new) +{ + return syscall(__NR_rt_sigaction, sig, old, new, sizeof(sigset_t)); +} + +static inline int sysinfo(void *ptr) +{ + return syscall(__NR_sysinfo, ptr); +} + +TEST(test_copy_to_user) +{ + struct sysinfo my_sysinfo; + + // Ensure that valid capabilities are successfully copied. + ASSERT_EQ(sysinfo(&my_sysinfo), 0); + + // Test copying a capability which has an invalid tag. + ASSERT_EQ(sysinfo(cheri_tag_clear(&my_sysinfo)), -EFAULT); + + // Test copying a capability which has invalid permissions. + ASSERT_EQ(sysinfo(cheri_perms_and(&my_sysinfo, 0)), -EFAULT); +} + +/* + * sigaction() tests both copy_to_user and copy_from_user by copying + * into and from a pointer to struct sigaction. The resulting action + * in this case is a no-op, but this does not affect the validity of + * the test. sigaction attempts to copy the new action from user space + * and the old action to user space, if the arguments is valid in either + * case. + */ +TEST(test_copy_user) +{ + struct sigaction act; + + // Check valid capabilities are successfully copied. + ASSERT_EQ(sigaction(SIGSEGV, NULL, &act), 0); + ASSERT_EQ(sigaction(SIGSEGV, &act, NULL), 0); + + /* + * Capabilities with a cleared tag must not be successfully copied + * from nor into user space. + */ + ASSERT_EQ(sigaction(SIGSEGV, NULL, cheri_tag_clear(&act)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, cheri_tag_clear(&act), NULL), -EFAULT); + + /* + * Capabilities with invalid permissions (simulated here with 0) must + * not be successfully copied to or from user space. + */ + ASSERT_EQ(sigaction(SIGSEGV, NULL, cheri_perms_and(&act, 0)), -EFAULT); + ASSERT_EQ(sigaction(SIGSEGV, cheri_perms_and(&act, 0), NULL), -EFAULT); +} + +typedef unsigned short sa_family_t; + +struct sockaddr { + sa_family_t sa_family; + char sa_data[14]; +}; + +/* + * getsockname(2) uses both get_user and put_user to copy the addrlen argument + * from and to user space respectively. If copy_to_user works successfully, + * getsockname(2) will return -EFAULT if either get_user or put_user fail. + */ +TEST(test_get_put_user) +{ + struct sockaddr sa; + int sa_len = sizeof(sa); + int my_socket; + + // socket(AF_INET, SOCK_STREAM, 0) + my_socket = syscall(__NR_socket, 2, 1, 0); + + // The socket must be successfully opened before proceeding. + ASSERT_GE(my_socket, 0); + + ASSERT_EQ(getsockname(my_socket, &sa, &sa_len), 0) + goto cleanup; + // Test with cleared capability tag. + ASSERT_EQ(getsockname(my_socket, &sa, cheri_tag_clear(&sa_len)), -EFAULT) + goto cleanup; + // Test with invalid capability permissions. + ASSERT_EQ(getsockname(my_socket, &sa, cheri_perms_and(&sa_len, 0)), -EFAULT) + goto cleanup; + + /* + * If any of the getsockname syscalls failed, then the socket is + * still open and must be closed before the test exits. + */ +cleanup: + ASSERT_EQ(close(my_socket), 0); +} + +/* + * The futex_waitv syscall explicitly checks the uaddr field of the individual + * futex waiters which is provided by a capability. This capability enforcement + * is therefore tested here; in the case where the capability is valid, the + * syscall should return -ETIMEDOUT as the futex waiter requires another thread + * to signal that it should wake up using futex_wake(). futex_wait() is not + * called in this thread, thus causing a timeout to occur. + */ +TEST(test_futex) +{ + struct timespec to = {.tv_sec = 0, .tv_nsec = 500000000}; + int res; + + // Test with valid capabilities. + for (int i = 0; i < NR_FUTEXES; i++) { + waitv[i].uaddr = (uintptr_t)&futexes[i]; + waitv[i].flags = FUTEX_32 | FUTEX_PRIVATE_FLAG; + waitv[i].val = futexes[i]; + waitv[i].__reserved = 0; + } + + res = futex_waitv(waitv, NR_FUTEXES, 0, &to, CLOCK_MONOTONIC); + ASSERT_EQ(res, -ETIMEDOUT); + + for (int i = 0; i < NR_FUTEXES; i++) + waitv[i].uaddr = (uintptr_t)cheri_tag_clear(&futexes[i]); + + + res = futex_waitv(waitv, NR_FUTEXES, 0, &to, CLOCK_MONOTONIC); + ASSERT_EQ(res, -EFAULT); + + for (int i = 0; i < NR_FUTEXES; i++) + waitv[i].uaddr = (uintptr_t)cheri_perms_and(&futexes[i], 0); + + + res = futex_waitv(waitv, NR_FUTEXES, 0, &to, CLOCK_MONOTONIC); + ASSERT_EQ(res, -EFAULT); +} + +/* + * Test explicit accesses used in iov_iter via readv and writev. Both + * syscalls use explicit checking on the iov_base field of struct iovec, + * so the metadata of the capability provided for iov_base is modified as + * per the needs of each individual test. + */ +TEST(test_explicit_iov_iter) +{ + char buf0[2]; + char buf1[4]; + char buf2[6]; + char *write_buf0 = "Hello I am the first char buffer!\n"; + char *write_buf1 = "Hello, I am the second char buffer.\n"; + char *write_buf2 = "Hello, I am the third and final char buffer.\n"; + struct iovec iov[3]; + int iovcnt; + + fd = open_file(); + ASSERT_NE(fd, -1); + + // Set up buffers for reading. + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + // Make sure readv works as expected with intact buf0. + ASSERT_GE(readv(fd, iov, iovcnt), 0) goto cleanup; + + // Clear the tag for the pointer to buf0. + iov[0].iov_base = cheri_tag_clear(buf0); + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT) goto cleanup; + + // Clear permissions, but restore the tag for buf0. + iov[0].iov_base = buf0; + iov[0].iov_base = cheri_perms_and(buf0, 0); + ASSERT_EQ(readv(fd, iov, iovcnt), -EFAULT) goto cleanup; + + // Set up buffers for writing. + iov[0].iov_base = write_buf0; + iov[0].iov_len = sizeof(write_buf0); + iov[1].iov_base = write_buf1; + iov[1].iov_len = sizeof(write_buf1); + iov[2].iov_base = write_buf2; + iov[2].iov_len = sizeof(write_buf2); + + // Make sure writev works as expected for buf0. + ASSERT_GE(writev(fd, iov, iovcnt), 0) goto cleanup; + + // Clear the tag for the pointer to buf0. + iov[0].iov_base = cheri_tag_clear(write_buf0); + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT) goto cleanup; + + // Clear permissions, but restore the tag for buf0. + iov[0].iov_base = write_buf0; + iov[0].iov_base = cheri_perms_and(write_buf0, 0); + ASSERT_EQ(writev(fd, iov, iovcnt), -EFAULT) goto cleanup; + +cleanup: + close(fd); +} + +/* + * strlen_user() explicitly inspects an input capability, the behaviour + * of which must also be verified within these tests. The fsopen() syscall + * makes use of strlen_user() by duplicating a string (representing the name + * of a filesystem) with the strndup_user() function. strlen_user() can + * therefore be tested with a call to fsopen(). + */ +TEST(test_strlen_user) +{ + char *fsname = "my_nonexistent_filesystem"; + + // strndup_user() will still be called, so fsopen() fails after this. + ASSERT_EQ(fsopen(&fsname), -ENODEV); + + // Clear the tag for the input capability to strndup_user(). + ASSERT_EQ(fsopen(cheri_tag_clear(&fsname)), -EFAULT); + + // Clear the permissions for the input capability to strndup_user(). + ASSERT_EQ(fsopen(cheri_perms_and(&fsname, 0)), -EFAULT); +} + +int main(void) +{ + test_copy_to_user(); + test_copy_user(); + test_get_put_user(); + test_futex(); + test_explicit_iov_iter(); + test_strlen_user(); + return 0; +} -- 2.34.1

1 year, 9 months

2
2
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[PATCH RFC v2 00/19] Introduce mm reservation interface for PCuABI

by Amit Daniel Kachhap

Hi All, This patch series introduces the mm reservation interface to manage the owning capability of the allocated addresses. As compared to the RFC v1, this series adds reservation details in the VMA structure. Looking for feedback regarding interface names, interface directory structure etc. Patch [1-11] manages capability bounds via reservation interface. Patch [12-19] adds support for managing capability permissions. Details about several rules implemented can be found in PCuABI spec here [1]. Changes in RFC v2: 1) Removed separate maple tree structures for the reservation interface and modified the vma structure to add the reservation details. As most of the mmap/munmap operations happen per-vma so this reduced the code churnings. However this approach will increase time-complexity of syscalls which operate across vma's such as mlock, madvise etc. get_unmapped_area() which generated free unmapped virtual address may now need more iterations. 2) Added Cheri base representability and length representability modifications. Now get_unmapped_area() will generate CHERI representable addresses. 3) Added new PCuABI changes for mincore() syscall. 4) Added changes for compat64. Future works: 1) Users of vm_mmap/vm_munmap() i.e. filesystems, loaders, kexec etc to be modified to preserve capability addresses. 2) Cover remaining memory addressing syscalls. Testing: 1) All tests by Chaitanya in v4 selftests [2] passes. 2) Purecap/Compat Busybox boot passes after adding [WIP] patches present in [3]. The whole series can be found here [3]. [1]: https://git.morello-project.org/morello/kernel/linux/-/wikis/Morello-pure-c… [2]: https://git.morello-project.org/chaitanya_prakash/linux.git review/purecap_mmap_testcases [3]: https://git.morello-project.org/amitdaniel/linux.git review/purecap_mm_reservation_v2 Thanks, Amit Daniel Amit Daniel Kachhap (19): uapi: errno.h: Introduce PCuABI memory reservation error arm64: morello: Add VM_PCUABI_RESERVE flags mm: Add capability reservation interfaces in vma for PCuABI mm/cap_addr_mgmt: Add capability bound helpers for PCuABI mm/mmap: Modify unmapped address space management code for PCuABI mm/mmap: Use the PCuABI reservations in mmap/munmap mm/mremap: Add the PCuABI reservation interfaces mm/mprotect: Add the PCuABI reservation interfaces mm/madvise: Add the PCuABI reservation interfaces mm/mlock: Add the PCuABI reservation interfaces mm/msync: Add the PCuABI reservation interfaces uapi: mman-common.h: Macros for maximum capability permissions mm/cap_addr_mgmt: Add capability permission helpers for PCuABI mm/cap_addr_mgmt: Reduce the maximum protection check impact mm/mmap: Disable MAP_GROWSDOWN mapping flag for PCuABI mm/mmap: Add capability permission constraints for PCuABI mm/mremap: Add capability permission constraints for PCuABI mm/mprotect: Add capability permission constraints for PCuABI mm/mincore: Add capability constraints for PCuABI arch/arm64/include/asm/cap_addr_mgmt.h | 22 ++ include/linux/cap_addr_mgmt.h | 168 +++++++++++++ include/linux/cheri.h | 3 + include/linux/mm.h | 29 ++- include/linux/mm_types.h | 5 + include/uapi/asm-generic/errno.h | 2 + include/uapi/asm-generic/mman-common.h | 6 + io_uring/advise.c | 2 +- mm/Makefile | 2 +- mm/cap_addr_mgmt.c | 314 +++++++++++++++++++++++++ mm/damon/vaddr.c | 2 +- mm/madvise.c | 27 ++- mm/mincore.c | 46 +++- mm/mlock.c | 38 ++- mm/mmap.c | 182 ++++++++++++-- mm/mprotect.c | 21 +- mm/mremap.c | 109 +++++++-- mm/msync.c | 15 +- mm/util.c | 10 +- 19 files changed, 919 insertions(+), 84 deletions(-) create mode 100644 arch/arm64/include/asm/cap_addr_mgmt.h create mode 100644 include/linux/cap_addr_mgmt.h create mode 100644 mm/cap_addr_mgmt.c -- 2.25.1

1 year, 10 months

2
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[PATCH] uaccess_testing: Testing of capability enforcement in uaccess

by Akram Ahmad

Add tests for capability enforcement via the standard copy routines (copy_{to, from}_user, {get, put}_user), futex operations and the explicit uaccess checks used in iov_iter via readv and writev. Signed-off-by: Akram Ahmad <Akram.Ahmad(a)arm.com> --- Hi everyone, This patch extends kselftests with tests for various uaccess routines. Broadly speaking, this tests the standard uaccess routines, futex operations, and iov_iter (the latter is implemented by testing readv and writev syscalls). The tests currently examine the effects of passing a capability with a cleared tag, invalid permissions, and an invalid base address offset. These are tested separately from one another, and I would especially appreciate any comments on how this could be improved if needed (particularly on the futex test). Thank you and happy holidays! Akram [1] The branch for this patch: https://git.morello-project.org/arkamnite/linux/-/commits/morello%2Fuaccess [2] The issue ticket for this patch: https://git.morello-project.org/morello/kernel/linux/-/issues/58 tools/testing/selftests/Makefile | 1 + .../testing/selftests/arm64/morello/Makefile | 2 +- .../testing/selftests/arm64/morello/uaccess.c | 491 ++++++++++++++++++ 3 files changed, 493 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/morello/uaccess.c diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 90a62cf75008..82abe4ddbb29 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -86,6 +86,7 @@ TARGETS += timers endif TARGETS += tmpfs TARGETS += tpm2 +TARGETS += uaccess TARGETS += user TARGETS += vDSO TARGETS += mm diff --git a/tools/testing/selftests/arm64/morello/Makefile b/tools/testing/selftests/arm64/morello/Makefile index ecfa6fc5e989..7b794d3e436c 100644 --- a/tools/testing/selftests/arm64/morello/Makefile +++ b/tools/testing/selftests/arm64/morello/Makefile @@ -17,7 +17,7 @@ CFLAGS += $(CLANG_FLAGS) $(CFLAGS_PURECAP) $(CFLAGS_COMMON) LDFLAGS += $(CLANG_LDFLAGS) $(CLANG_FLAGS) -nostdlib -static SRCS := $(wildcard *.c) $(wildcard *.S) -PROGS := bootstrap clone exit mmap read_write sched signal +PROGS := bootstrap clone exit mmap read_write sched signal uaccess DEPS := $(wildcard *.h) # these are the final executables diff --git a/tools/testing/selftests/arm64/morello/uaccess.c b/tools/testing/selftests/arm64/morello/uaccess.c new file mode 100644 index 000000000000..66d93137b819 --- /dev/null +++ b/tools/testing/selftests/arm64/morello/uaccess.c @@ -0,0 +1,491 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2023 Arm Limited + +#include <stdint.h> +#include <stddef.h> +#include <stdbool.h> + +#include <asm/fcntl.h> +#include <asm-generic/errno-base.h> +#include <cheriintrin.h> +#include <linux/fs.h> +#include <linux/futex.h> +#include <linux/mman.h> +#include <linux/sysinfo.h> +#include <linux/socket.h> +#include <linux/time.h> +#include <linux/uio.h> + +#include "freestanding.h" + +#define FILE_PERM 0666 +#define MSG_LEN 16 +#define NR_FUTEXES 2 + +static struct futex_waitv waitv[NR_FUTEXES]; +uint32_t futexes[NR_FUTEXES] = {1}; + +static const char file[] = "/my_file.txt"; +static int fd; +static int my_socket; + +static int open_file(void) +{ + return syscall(__NR_openat, 0, file, O_RDWR | O_CREAT, 0666); +} + +static int close_file(int __fd) +{ + return syscall(__NR_close, __fd); +} + +static __always_inline +void copy_to_user1(void) +{ + int result; + struct sysinfo my_sysinfo; + struct sysinfo *p_si = &my_sysinfo; + struct sysinfo my_sysinfo2; + struct sysinfo *p_si2 = &my_sysinfo2 + 10 * sizeof(struct sysinfo); + + result = syscall(__NR_sysinfo, p_si); + TH_LOG("%s: sysinfo with valid capability", __func__); + ASSERT_EQ(result, 0); + + TH_LOG("%s: sysinfo with invalid capability offset", __func__); + result = syscall(__NR_sysinfo, p_si2); + ASSERT_EQ(result, -EFAULT); +} + +static __always_inline +void copy_to_user2(void) +{ + int result; + struct sysinfo my_sysinfo; + struct sysinfo *cap = &my_sysinfo; + + TH_LOG("%s: sysinfo with cleared capability tag", __func__); + cap = (struct sysinfo *)cheri_tag_clear(cap); + result = syscall(__NR_sysinfo, cap); + ASSERT_EQ(result, -EFAULT); +} + +static __always_inline +void copy_to_user3(void) +{ + int result; + struct sysinfo my_sysinfo; + struct sysinfo *cap = &my_sysinfo; + + TH_LOG("%s: sysinfo with no capability permissions", __func__); + cap = (struct sysinfo *)cheri_perms_and(cap, 0); + result = syscall(__NR_sysinfo, cap); + ASSERT_EQ(result, -EFAULT); +} + +TEST(test_copy_to_user) +{ + copy_to_user1(); + copy_to_user2(); + copy_to_user3(); +} + +static __always_inline +void copy_from_user1(void) +{ + int result; + size_t my_offset = sizeof(int); + size_t *good_p = &my_offset; + size_t *bad_p = &my_offset + sizeof(int); + + /** + * Setup the parameters for our syscall: + * fd_in, fd_out: these can be the same fd. + * off_in: the capability pointing to a buffer for the offset + * off_out: NULL, as we do not need this. + * len: MSG_LEN + */ + fd = open_file(); + + result = syscall(__NR_copy_file_range, fd, good_p, fd, NULL, MSG_LEN, 0); + TH_LOG("%s: copy_file_range with valid capability", __func__); + ASSERT_GE(0, result); + + result = syscall(__NR_copy_file_range, fd, bad_p, fd, NULL, MSG_LEN, 0); + TH_LOG("%s: copy_file_range with invalid capability offset", __func__); + ASSERT_EQ(result, -EFAULT); + close_file(fd); +} + +static __always_inline +void copy_from_user2(void) +{ + int result; + size_t my_offset = sizeof(int); + size_t *good_p = &my_offset; + size_t *bad_p = (size_t *)cheri_tag_clear(good_p); + + fd = open_file(); + + result = syscall(__NR_copy_file_range, fd, bad_p, fd, NULL, MSG_LEN, 0); + TH_LOG("%s: copy_file_range with cleared capability tag", __func__); + ASSERT_EQ(result, -EFAULT); + close_file(fd); +} + +static __always_inline +void copy_from_user3(void) +{ + int result; + size_t my_offset = sizeof(int); + size_t *bad_p = (size_t *)cheri_perms_and(&my_offset, 0); + + fd = open_file(); + + result = syscall(__NR_copy_file_range, fd, bad_p, fd, NULL, MSG_LEN, 0); + TH_LOG("%s: copy_file_range with capability with no permissions", __func__); + ASSERT_EQ(result, -EFAULT); + close_file(fd); +} + +TEST(test_copy_from_user) +{ + copy_from_user1(); + copy_from_user2(); + copy_from_user3(); +} + +typedef unsigned short sa_family_t; + +struct sockaddr { + sa_family_t sa_family; + char sa_data[14]; +}; + +static __always_inline +void get_user1(void) +{ + int result; + struct sockaddr sa; + struct sockaddr sa2; + struct sockaddr *my_sockaddr_ptr = &sa2 + sizeof(int) * 1000; + + // socket(AF_INET, SOCK_STREAM, 0) + my_socket = syscall(__NR_socket, 2, 1, 0); + TH_LOG("%s: socket syscall complete", __func__); + ASSERT_GE(my_socket, 0); + + int sa_len = sizeof(sa); + int *my_len_pointer = &sa_len; + + TH_LOG("%s: getsockname with valid capability", __func__); + result = syscall(__NR_getsockname, my_socket, &sa, &sa_len); + ASSERT_EQ(result, 0); + + sa_len = sizeof(sa2); + TH_LOG("%s: getsockname with invalid capability offset", __func__); + result = syscall(__NR_getsockname, my_socket, my_sockaddr_ptr, my_len_pointer); + ASSERT_EQ(result, -EFAULT); +} + +static __always_inline +void get_user2(void) +{ + int result; + struct sockaddr sa; + int sa_len = sizeof(sa); + struct sockaddr *p_sockaddr = cheri_tag_clear(&sa); + + // socket(AF_INET, SOCK_STREAM, 0) + my_socket = syscall(__NR_socket, 2, 1, 0); + ASSERT_GE(my_socket, 0); + + result = syscall(__NR_getsockname, my_socket, p_sockaddr, &sa_len); + TH_LOG("%s: getsockname with cleared capability tag", __func__); + ASSERT_EQ(result, -EFAULT); +} + +static __always_inline +void get_user3(void) +{ + int result; + struct sockaddr sa; + int sa_len = sizeof(sa); + struct sockaddr *p_sockaddr = cheri_perms_and(&sa, 0); + + // socket(AF_INET, SOCK_STREAM, 0) + my_socket = syscall(__NR_socket, 2, 1, 0); + ASSERT_GE(my_socket, 0); + + result = syscall(__NR_getsockname, my_socket, p_sockaddr, &sa_len); + TH_LOG("%s: getsockname with no capability permissions", __func__); + ASSERT_EQ(result, -EFAULT); +} + +TEST(test_get_user) +{ + get_user1(); + get_user2(); + get_user3(); +} + +static __always_inline +void put_user1(void) +{ + int result; + struct timeval tv; + struct timeval *p_tv = &tv; + + result = syscall(__NR_gettimeofday, p_tv, NULL); + TH_LOG("%s: gettimeofday with valid capability", __func__); + ASSERT_EQ(result, 0); + + p_tv = &tv + sizeof(struct timeval) * 1000; + result = syscall(__NR_gettimeofday, p_tv, NULL); + TH_LOG("%s: gettimeofday with invalid capability offset", __func__); + ASSERT_EQ(result, -EFAULT); +} + +static __always_inline +void put_user2(void) +{ + int result; + struct timeval tv; + struct timeval *p_tv = &tv; + + p_tv = cheri_tag_clear(p_tv); + result = syscall(__NR_gettimeofday, p_tv, NULL); + TH_LOG("%s: gettimeofday with cleared capability tag", __func__); + ASSERT_EQ(result, -EFAULT); +} + +static __always_inline +void put_user3(void) +{ + int result; + struct timeval tv; + struct timeval *p_tv = &tv; + + p_tv = cheri_perms_and(p_tv, 0); + result = syscall(__NR_gettimeofday, p_tv, NULL); + TH_LOG("%s: gettimeofday with capability with no permissions", __func__); + ASSERT_EQ(result, -EFAULT); +} + +TEST(test_put_user) +{ + put_user1(); + put_user2(); + put_user3(); +} + +static inline int futex_waitv(volatile struct futex_waitv *waiters, unsigned long nr_waiters, + unsigned long flags, struct timespec *timo, clockid_t clockid) +{ + return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, timo, clockid); +} + +static __always_inline +void futex1(void) +{ + struct timespec to; + + for (int i = 0; i < NR_FUTEXES; i++) { + waitv[i].uaddr = (uintptr_t)cheri_tag_clear(&futexes[i]); + waitv[i].flags = FUTEX_32 | FUTEX_PRIVATE_FLAG; + waitv[i].val = i; + waitv[i].__reserved = 0; + // This is necessary otherwise the loop is optimised away + TH_LOG("%s: waitv[%d] initialised", __func__, i); + } + + int res = futex_waitv(waitv, NR_FUTEXES, 0, &to, CLOCK_MONOTONIC); + + ASSERT_EQ(res, -EFAULT); +} + +TEST(test_futex) +{ + futex1(); +} + +static __always_inline +void explicit_readv1(void) +{ + ssize_t bytes_read; + char buf0[2]; + char buf1[4]; + char buf2[6]; + struct iovec iov[3]; + int iovcnt; + + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + fd = open_file(); + TH_LOG("%s: readv with valid capability", __func__); + bytes_read = syscall(__NR_readv, fd, iov, iovcnt); + close_file(fd); + ASSERT_GE(bytes_read, 0); +} + +static __always_inline +void explicit_readv2(void) +{ + ssize_t bytes_read; + char buf0[2]; + char buf1[4]; + char buf2[6]; + struct iovec iov[3]; + int iovcnt; + + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + fd = open_file(); + TH_LOG("%s: readv with invalid capability tag", __func__); + bytes_read = syscall(__NR_readv, fd, cheri_tag_clear(iov), iovcnt); + close_file(fd); + ASSERT_EQ(bytes_read, -EFAULT); +} + +static __always_inline +void explicit_readv3(void) +{ + ssize_t bytes_read; + char buf0[2]; + char buf1[4]; + char buf2[6]; + struct iovec iov[3]; + int iovcnt; + + iov[0].iov_base = cheri_perms_and(buf0, 0); + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + fd = open_file(); + TH_LOG("%s: readv with invalid capability permissions", __func__); + bytes_read = syscall(__NR_readv, fd, cheri_perms_and(iov, 0), iovcnt); + close_file(fd); + ASSERT_EQ(bytes_read, -EFAULT); +} + +static __always_inline +void explicit_writev1(void) +{ + ssize_t bytes_written; + char *buf0 = "Hello I am the first char buffer!\n"; + char *buf1 = "Hello, I am the second char buffer.\n"; + char *buf2 = "Hello, I am the third and final char buffer.\n"; + struct iovec iov[3]; + int iovcnt; + + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + fd = open_file(); + TH_LOG("%s: writev with valid capability", __func__); + bytes_written = syscall(__NR_writev, fd, iov, iovcnt); + close_file(fd); + ASSERT_GE(bytes_written, 0); +} + +static __always_inline +void explicit_writev2(void) +{ + ssize_t bytes_written; + char *buf0 = "Hello I am the first char buffer!\n"; + char *buf1 = "Hello, I am the second char buffer.\n"; + char *buf2 = "Hello, I am the third and final char buffer.\n"; + struct iovec iov[3]; + int iovcnt; + + iov[0].iov_base = buf0; + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + fd = open_file(); + TH_LOG("%s: writev with invalid capability tag", __func__); + bytes_written = syscall(__NR_writev, fd, cheri_tag_clear(iov), iovcnt); + close_file(fd); + ASSERT_EQ(bytes_written, -EFAULT); +} + +static __always_inline +void explicit_writev3(void) +{ + ssize_t bytes_written; + char *buf0 = "Hello I am the first char buffer!\n"; + char *buf1 = "Hello, I am the second char buffer.\n"; + char *buf2 = "Hello, I am the third and final char buffer.\n"; + struct iovec iov[3]; + int iovcnt; + + iov[0].iov_base = cheri_perms_and(buf0, 0); + iov[0].iov_len = sizeof(buf0); + iov[1].iov_base = buf1; + iov[1].iov_len = sizeof(buf1); + iov[2].iov_base = buf2; + iov[2].iov_len = sizeof(buf2); + + iovcnt = sizeof(iov) / sizeof(struct iovec); + + fd = open_file(); + TH_LOG("%s: writev with invalid capability permissions", __func__); + bytes_written = syscall(__NR_writev, fd, cheri_perms_and(iov, 0), iovcnt); + close_file(fd); + ASSERT_EQ(bytes_written, -EFAULT); +} + +/* + * Test readv and writev where the array of iovecs is provided + * by a capability. + */ +TEST(test_explicit_iov_iter) +{ + explicit_readv1(); + explicit_readv2(); + explicit_readv3(); + explicit_writev1(); + explicit_writev2(); + explicit_writev3(); +} + +int main(void) +{ + test_copy_to_user(); + test_copy_from_user(); + test_get_user(); + test_put_user(); + test_futex(); + test_explicit_iov_iter(); + return 0; +} -- 2.34.1

1 year, 10 months

2
1
0 0

[PATCH] selftests/vDSO: Fix type casts in get_sysinfo_ehdr()

by Aditya Deshpande

Cast the return value of getauxptr() from void* to uintptr_t (which is defined as __uintcap_t in purecap) to address compiler warnings. Remove the unnecessary cast on getauxval(), as uintptr_t is defined as unsigned long in non-purecap anyway. Signed-off-by: Aditya Deshpande <aditya.deshpande(a)arm.com> --- Hi all, This is a minor follow up patch to the vDSO series which fixes a compiler warning about implicit type casts. The current state of the vDSO tests shouldn't cause any issues with the release as: 1. This is just a compiler warning - the test code is still functionally correct. 2. The vDSO selftests are built standalone anyways. Thanks, Aditya --- tools/testing/selftests/vDSO/parse_vdso.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/vDSO/parse_vdso.h b/tools/testing/selftests/vDSO/parse_vdso.h index 54ad67f463cc..9c891a12be7d 100644 --- a/tools/testing/selftests/vDSO/parse_vdso.h +++ b/tools/testing/selftests/vDSO/parse_vdso.h @@ -38,9 +38,9 @@ void vdso_init_from_auxv(void *auxv); static inline uintptr_t get_sysinfo_ehdr() { #ifdef __CHERI_PURE_CAPABILITY__ - return getauxptr(AT_SYSINFO_EHDR); + return (uintptr_t)getauxptr(AT_SYSINFO_EHDR); #else - return (uintptr_t)getauxval(AT_SYSINFO_EHDR); + return getauxval(AT_SYSINFO_EHDR); #endif } -- 2.25.1

1 year, 10 months

2
1
0 0

[PATCH v6 00/13] update bpf syscall for PCuABI/compat64

by Zachary Leaf

Hi, Here's v6. The bpf syscall is updated to propagate user pointers as capabilities in the pure-capability kernel-user ABI (PCuABI). It also includes an approach to support the existing aarch64 ABI (compat64). One complication here is from the fact this syscall supports many multiplexed sub-commands, some of which are themselves multiplexed with a number of further nested/multiplexed options. Another complication is that the existing syscall uses a trick of storing user pointers as u64 to avoid needing a compat handler for 32-bit systems. To retain compatibility with the aarch64 ABI and add Morello support, special compat64 conversion and handling is implemented. Inbound (userspace->kernel) conversion between compat64/native struct layouts is handled upfront on entry to the syscall (with the exception of bpf_xyz_info structs - see patch 8). This minimises changes to sub-command handlers. Some sub-commands require conversion back out to userspace and that by necessity is handled where it occurs. Patch 1 is not essential to this series but it's a nice debug feature to have and works[1]. It enables BPF_PROG_TYPE_TRACEPOINT which many eBPF kselftests use. Patches 5,6,8 implement the core compat64 handling. Each commit compiles cleanly but relevant parts will be broken inbetween. Patch 9 fixes the CHECK_ATTR macro to also check configs passed in via compat64. Patch 11 finally enables capabilities in the kernel. Patches 12,13 handles uaccess that occurs in two eBPF helper functions. The rest are setup/helper functions. Testing wise, see associated LTP changes below as posted to LTP mailing list[2]. The eBPF LTP tests are fairly minimal and test only a small part of the changes here. There's a new test to test CHECK_ATTR from patch 9. The kernel kselftests contain many more extensive eBPF tests. They can be built fairly easily natively on aarch64 which is useful for testing compat64. More work needs to be done here though to: a) enable out-of-tree cross-compilation for purecap as well as x86->aarch64 b) replace ptr_to_u64() with casts to uintptr_t in tests c) general libbpf/bpftool enablement and fixes since many tests rely on this d) CONFIG_DEBUG_INFO_BTF required for many tests but this requires the build system to have a recent version of pahole tool Next steps once we have the core kernel support would be porting libbpf and bpftool for purecap plus work on enabling kselftests as above. Kernel branch available at: https://git.morello-project.org/zdleaf/linux/-/tree/morello/bpf_v6 Associated LTP test/changes at: https://git.morello-project.org/zdleaf/morello-linux-test-project/-/tree/mo… Thanks, Zach [1] [PATCH v3 0/5] Restore syscall tracing on Morello https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [2] [PATCH v2 0/3] add eBPF support https://op-lists.linaro.org/archives/list/linux-morello-ltp@op-lists.linaro… ----------------------------------------------------------------------- v6: - Re-work BPF_LINK_CREATE memcpy in convert_compat_bpf_attr() v5: - Simplify BPF_LINK_CREATE handling in bpf/syscall.c:convert_compat_bpf_attr() - Add missing bpf_compat_ptr_field() - Re-work/fix check_attr() to catch missing enum bpf_cmd values [...] [0] [RFC PATCH 0/9] update bpf syscall for PCuABI/compat64 https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [1] [PATCH 00/10] update bpf syscall for PCuABI/compat64 https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [2] [PATCH v2 00/12] update bpf syscall for PCuABI/compat64 https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [3] [PATCH v3 00/12] update bpf syscall for PCuABI/compat64 https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [4] [PATCH v4 00/12] update bpf syscall for PCuABI/compat64 https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… [5] [PATCH v5 00/12] update bpf syscall for PCuABI/compat64 https://op-lists.linaro.org/archives/list/linux-morello@op-lists.linaro.org… ----------------------------------------------------------------------- Zachary Leaf (13): arm64: morello: enable syscall tracing arch: rename 32bit_compat to compat32 arch: add compat helpers specific to 64-bit stddef: introduce copy_field helper bpf: compat64: add handler and convert bpf_attr in bpf: compat64: bpf_attr convert out bpf/btf: move zero check into btf.c bpf: compat64: handle bpf_{btf,prog,link}_info bpf: compat64: support CHECK_ATTR macro bpf: copy_{to,from}_user_with_ptr helpers bpf: use user pointer types in uAPI structs bpf: use addr for bpf_copy_from_user_with_task bpf: use addr for bpf_copy_from_user .../morello_transitional_pcuabi_defconfig | 2 +- arch/arm64/include/asm/compat.h | 11 +- arch/arm64/include/asm/ftrace.h | 2 +- arch/arm64/include/asm/mmu_context.h | 2 +- arch/arm64/include/asm/syscall.h | 6 +- arch/arm64/kernel/fpsimd.c | 6 +- arch/arm64/kernel/hw_breakpoint.c | 2 +- arch/arm64/kernel/perf_regs.c | 2 +- arch/arm64/kernel/pointer_auth.c | 6 +- arch/arm64/kernel/process.c | 16 +- arch/arm64/kernel/ptrace.c | 10 +- arch/arm64/kernel/signal.c | 2 +- arch/arm64/kernel/syscall.c | 2 +- arch/mips/include/asm/compat.h | 2 +- arch/parisc/include/asm/compat.h | 2 +- arch/powerpc/include/asm/compat.h | 2 +- arch/s390/include/asm/compat.h | 2 +- arch/sparc/include/asm/compat.h | 4 +- arch/x86/include/asm/compat.h | 2 +- drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 2 +- drivers/gpu/drm/amd/amdkfd/kfd_process.c | 2 +- drivers/input/input.c | 2 +- drivers/media/rc/bpf-lirc.c | 6 +- fs/ext4/dir.c | 2 +- fs/nfs/dir.c | 2 +- include/linux/bpf.h | 19 + include/linux/bpf_compat.h | 415 +++++++++ include/linux/bpfptr.h | 28 +- include/linux/compat.h | 16 +- include/linux/stddef.h | 3 + include/uapi/linux/bpf.h | 94 +- kernel/bpf/bpf_iter.c | 2 +- kernel/bpf/btf.c | 104 ++- kernel/bpf/cgroup.c | 9 +- kernel/bpf/hashtab.c | 12 +- kernel/bpf/helpers.c | 9 +- kernel/bpf/net_namespace.c | 6 +- kernel/bpf/offload.c | 2 +- kernel/bpf/syscall.c | 842 ++++++++++++++---- kernel/bpf/verifier.c | 20 +- kernel/time/time.c | 2 +- kernel/trace/bpf_trace.c | 6 +- mm/util.c | 2 +- net/bpf/bpf_dummy_struct_ops.c | 8 +- net/bpf/test_run.c | 31 +- net/core/sock_map.c | 6 +- 46 files changed, 1393 insertions(+), 342 deletions(-) create mode 100644 include/linux/bpf_compat.h -- 2.34.1

1 year, 10 months

2
14
0 0

[Announcement] Integration drop 1.7.0 - changelog

by Kevin Brodsky

Hi, The top of the master branch has been tagged [1] as part of the integration drop 1.7.0. Below is the changelog for kernel users, since the previous integration drop (1.6.1). PCuABI-related changes ---------------------- * [Issue #24] A pure-capability vDSO is now provided in PCuABI. * [Issue #7] In a small number of situations, user-provided capabilities are now explicitly checked (validity, bounds and read/write permissions). This covers cases where user memory is accessed via a kernel mapping, instead of the standard approach where user mappings are used (uaccess). A section has also been added to the porting guide [2], as porting some drivers may require adding explicit checking. Note: patches have been posted on the list to enable capability checking in uaccess, but they are yet to be merged. * [Issue #46] The TCP_ZEROCOPY_RECEIVE getsockopt() option has been modified to operate on capabilities in PCuABI. A corresponding section has been added to the PCuABI specification [3]. * [Issue #51] MMC-related ioctl commands have been adapted to operate on capabilities. Other changes ------------- * KSM (Kernel Samepage Merging) is now disabled to avoid false positives when capability tags differ. It is unclear whether KSM would still be worthwhile with the extra overhead of comparing capability tags (issue #62 created to track this). * Internal refactoring to assist with upcoming changes. Contributions ------------- Kudos to everyone who has contributed to Morello Linux! Here are the contributors and number of patches since the previous integration drop: 10 Kevin Brodsky <kevin.brodsky(a)arm.com> 7 Luca Vizzarro <Luca.Vizzarro(a)arm.com> 6 Aditya Deshpande <aditya.deshpande(a)arm.com> 3 Harry Ramsey <harry.ramsey(a)arm.com> 2 Akram Ahmad <Akram.Ahmad(a)arm.com> Special thanks are also extended to everyone who has assisted in reviewing these patches. Cheers, Kevin [1] https://git.morello-project.org/morello/kernel/linux/-/commits/morello-rele… [2] https://git.morello-project.org/morello/kernel/linux/-/blob/morello-release… [3] https://git.morello-project.org/morello/kernel/linux/-/wikis/Morello-pure-c…

1 year, 10 months

1
0
0 0

Linux DRM purecap "RFC"

by Carsten Haitzler

Just thought it's time to share the current state of drm purecap work: Kernel: https://git.morello-project.org/carhai01/linux-drm-purecap/-/commit/7ea169a… DRM: https://git.morello-project.org/carhai01/drm-linux-morello-purecap/-/commit… All the DRM tests ow pass for compat and purecap. I'm of 2 minds in the kernel code. I could go mimic the "copy field" stuff from EBPF but it's still going to be a bit messy. DRM code calls everything "compat" "32" so I'm keeping with that naming scheme (compat for us is 64bit). I've kept the compat structs at the entry points. I could copy to a local "native" struct I guess... It'd mean I carry more local data than I actually need/use. Anyway... comments?

1 year, 11 months

2
5
0 0

2025

2024

2023

2022

linux-morello