| Message ID | 20180730201553.32423-2-richard.henderson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | linux-user/sparc: Fixes for clone | expand |
Richard Henderson <richard.henderson@linaro.org> writes: > Or really, just clone devolving into fork. This should not ever happen > in practice. We do want to reserve calling cpu_clone_regs for the case > in which we are actually performing a clone. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> > --- > linux-user/syscall.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/linux-user/syscall.c b/linux-user/syscall.c > index dfc851cc35..5bf8d13de7 100644 > --- a/linux-user/syscall.c > +++ b/linux-user/syscall.c > @@ -6502,10 +6502,14 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp, > pthread_mutex_destroy(&info.mutex); > pthread_mutex_unlock(&clone_lock); > } else { > - /* if no CLONE_VM, we consider it is a fork */ > + /* If no CLONE_VM, we consider it is a fork. */ > if (flags & CLONE_INVALID_FORK_FLAGS) { > return -TARGET_EINVAL; > } > + /* As a fork, setting a new sp does not make sense. */ > + if (newsp) { > + return -TARGET_EINVAL; > + } > > /* We can't support custom termination signals */ > if ((flags & CSIGNAL) != TARGET_SIGCHLD) { > @@ -6520,7 +6524,6 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp, > ret = fork(); > if (ret == 0) { > /* Child Process. */ > - cpu_clone_regs(env, newsp); > fork_end(1); > /* There is a race condition here. The parent process could > theoretically read the TID in the child process before the child -- Alex Bennée
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index dfc851cc35..5bf8d13de7 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -6502,10 +6502,14 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp, pthread_mutex_destroy(&info.mutex); pthread_mutex_unlock(&clone_lock); } else { - /* if no CLONE_VM, we consider it is a fork */ + /* If no CLONE_VM, we consider it is a fork. */ if (flags & CLONE_INVALID_FORK_FLAGS) { return -TARGET_EINVAL; } + /* As a fork, setting a new sp does not make sense. */ + if (newsp) { + return -TARGET_EINVAL; + } /* We can't support custom termination signals */ if ((flags & CSIGNAL) != TARGET_SIGCHLD) { @@ -6520,7 +6524,6 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp, ret = fork(); if (ret == 0) { /* Child Process. */ - cpu_clone_regs(env, newsp); fork_end(1); /* There is a race condition here. The parent process could theoretically read the TID in the child process before the child
Or really, just clone devolving into fork. This should not ever happen in practice. We do want to reserve calling cpu_clone_regs for the case in which we are actually performing a clone. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- linux-user/syscall.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)