diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux')
| -rw-r--r-- | sysdeps/unix/sysv/linux/Makefile | 3 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/clone-internal.c | 37 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/clone3.h | 7 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/spawni.c | 31 |
4 files changed, 52 insertions, 26 deletions
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index f298878e8f..f8bd12d991 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -269,8 +269,7 @@ tests-clone-internal = \ tst-align-clone-internal \ tst-clone2-internal \ tst-clone3-internal \ - tst-getpid1-internal \ - tst-misalign-clone-internal + tst-getpid1-internal tests-internal += $(tests-clone-internal) tests-static += $(tests-clone-internal) diff --git a/sysdeps/unix/sysv/linux/clone-internal.c b/sysdeps/unix/sysv/linux/clone-internal.c index a8611772a2..e125c9125e 100644 --- a/sysdeps/unix/sysv/linux/clone-internal.c +++ b/sysdeps/unix/sysv/linux/clone-internal.c @@ -44,27 +44,15 @@ _Static_assert (sizeof (struct clone_args) == CLONE_ARGS_SIZE_VER2, "sizeof (struct clone_args) != CLONE_ARGS_SIZE_VER2"); int -__clone_internal (struct clone_args *cl_args, - int (*func) (void *arg), void *arg) +__clone_internal_fallback (struct clone_args *cl_args, + int (*func) (void *arg), void *arg) { - int ret; -#ifdef HAVE_CLONE3_WRAPPER - /* Try clone3 first. */ - int saved_errno = errno; - ret = __clone3 (cl_args, sizeof (*cl_args), func, arg); - if (ret != -1 || errno != ENOSYS) - return ret; - - /* NB: Restore errno since errno may be checked against non-zero - return value. */ - __set_errno (saved_errno); -#endif - /* Map clone3 arguments to clone arguments. NB: No need to check invalid clone3 specific bits in flags nor exit_signal since this is an internal function. */ int flags = cl_args->flags | cl_args->exit_signal; void *stack = cast_to_pointer (cl_args->stack); + int ret; #ifdef __ia64__ ret = __clone2 (func, stack, cl_args->stack_size, @@ -88,4 +76,23 @@ __clone_internal (struct clone_args *cl_args, return ret; } + +int +__clone_internal (struct clone_args *cl_args, + int (*func) (void *arg), void *arg) +{ +#ifdef HAVE_CLONE3_WRAPPER + int saved_errno = errno; + int ret = __clone3 (cl_args, sizeof (*cl_args), func, arg); + if (ret != -1 || errno != ENOSYS) + return ret; + + /* NB: Restore errno since errno may be checked against non-zero + return value. */ + __set_errno (saved_errno); +#endif + + return __clone_internal_fallback (cl_args, func, arg); +} + libc_hidden_def (__clone_internal) diff --git a/sysdeps/unix/sysv/linux/clone3.h b/sysdeps/unix/sysv/linux/clone3.h index e4d642e521..451b156405 100644 --- a/sysdeps/unix/sysv/linux/clone3.h +++ b/sysdeps/unix/sysv/linux/clone3.h @@ -23,6 +23,13 @@ #include <stddef.h> #include <bits/types.h> + +/* Flags for the clone3 syscall. */ +#define CLONE_CLEAR_SIGHAND 0x100000000ULL /* Clear any signal handler and + reset to SIG_DFL. */ +#define CLONE_INTO_CGROUP 0x200000000ULL /* Clone into a specific cgroup given + the right permissions. */ + /* The unsigned 64-bit and 8-byte aligned integer type. */ typedef __U64_TYPE __aligned_uint64_t __attribute__ ((__aligned__ (8))); diff --git a/sysdeps/unix/sysv/linux/spawni.c b/sysdeps/unix/sysv/linux/spawni.c index a1a14a58ae..bc321d4c58 100644 --- a/sysdeps/unix/sysv/linux/spawni.c +++ b/sysdeps/unix/sysv/linux/spawni.c @@ -66,6 +66,7 @@ struct posix_spawn_args ptrdiff_t argc; char *const *envp; int xflags; + bool use_clone3; int err; }; @@ -104,12 +105,11 @@ __spawni_child (void *arguments) const posix_spawnattr_t *restrict attr = args->attr; const posix_spawn_file_actions_t *file_actions = args->fa; - /* The child must ensure that no signal handler are enabled because it shared - memory with parent, so the signal disposition must be either SIG_DFL or - SIG_IGN. It does by iterating over all signals and although it could - possibly be more optimized (by tracking which signal potentially have a - signal handler), it might requires system specific solutions (since the - sigset_t data type can be very different on different architectures). */ + /* The child must ensure that no signal handler is enabled because it + shares memory with parent, so all signal dispositions must be either + SIG_DFL or SIG_IGN. If clone3/CLONE_CLEAR_SIGHAND is used, there is + only the need to set the defined signals POSIX_SPAWN_SETSIGDEF to + SIG_DFL; otherwise, the code iterates over all signals. */ struct sigaction sa; memset (&sa, '\0', sizeof (sa)); @@ -122,7 +122,7 @@ __spawni_child (void *arguments) { sa.sa_handler = SIG_DFL; } - else if (__sigismember (&hset, sig)) + else if (!args->use_clone3 && __sigismember (&hset, sig)) { if (is_internal_signal (sig)) sa.sa_handler = SIG_IGN; @@ -382,12 +382,25 @@ __spawnix (pid_t * pid, const char *file, for instance). */ struct clone_args clone_args = { - .flags = CLONE_VM | CLONE_VFORK, + /* Unsupported flags like CLONE_CLEAR_SIGHAND will be cleared up by + __clone_internal_fallback. */ + .flags = CLONE_CLEAR_SIGHAND | CLONE_VM | CLONE_VFORK, .exit_signal = SIGCHLD, .stack = (uintptr_t) stack, .stack_size = stack_size, }; - new_pid = __clone_internal (&clone_args, __spawni_child, &args); +#ifdef HAVE_CLONE3_WRAPPER + args.use_clone3 = true; + new_pid = __clone3 (&clone_args, sizeof (clone_args), __spawni_child, + &args); + /* clone3 was added in 5.3 and CLONE_CLEAR_SIGHAND in 5.5. */ + if (new_pid == -1 && (errno == ENOSYS || errno == EINVAL)) +#endif + { + args.use_clone3 = false; + new_pid = __clone_internal_fallback (&clone_args, __spawni_child, + &args); + } /* It needs to collect the case where the auxiliary process was created but failed to execute the file (due either any preparation step or |