From 457677c70c7672a4586b0b8abc396cc1ecdd376d Mon Sep 17 00:00:00 2001 From: Amanieu d'Antras Date: Sat, 4 Jan 2020 13:39:30 +0100 Subject: [PATCH] um: Implement copy_thread_tls This is required for clone3 which passes the TLS value through a struct rather than a register. Signed-off-by: Amanieu d'Antras Cc: linux-um@lists.infradead.org Cc: # 5.3.x Link: https://lore.kernel.org/r/20200104123928.1048822-1-amanieu@gmail.com Signed-off-by: Christian Brauner --- arch/um/Kconfig | 1 + arch/um/include/asm/ptrace-generic.h | 2 +- arch/um/kernel/process.c | 6 +++--- arch/x86/um/tls_32.c | 6 ++---- arch/x86/um/tls_64.c | 7 +++---- 5 files changed, 10 insertions(+), 12 deletions(-) diff --git a/arch/um/Kconfig b/arch/um/Kconfig index 2a6d04fcb3e9..6f0edd0c0220 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -14,6 +14,7 @@ config UML select HAVE_FUTEX_CMPXCHG if FUTEX select HAVE_DEBUG_KMEMLEAK select HAVE_DEBUG_BUGVERBOSE + select HAVE_COPY_THREAD_TLS select GENERIC_IRQ_SHOW select GENERIC_CPU_DEVICES select GENERIC_CLOCKEVENTS diff --git a/arch/um/include/asm/ptrace-generic.h b/arch/um/include/asm/ptrace-generic.h index 81c647ef9c6c..adf91ef553ae 100644 --- a/arch/um/include/asm/ptrace-generic.h +++ b/arch/um/include/asm/ptrace-generic.h @@ -36,7 +36,7 @@ extern long subarch_ptrace(struct task_struct *child, long request, extern unsigned long getreg(struct task_struct *child, int regno); extern int putreg(struct task_struct *child, int regno, unsigned long value); -extern int arch_copy_tls(struct task_struct *new); +extern int arch_set_tls(struct task_struct *new, unsigned long tls); extern void clear_flushed_tls(struct task_struct *task); extern int syscall_trace_enter(struct pt_regs *regs); extern void syscall_trace_leave(struct pt_regs *regs); diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index 263a8f069133..17045e7211bf 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -153,8 +153,8 @@ void fork_handler(void) userspace(¤t->thread.regs.regs, current_thread_info()->aux_fp_regs); } -int copy_thread(unsigned long clone_flags, unsigned long sp, - unsigned long arg, struct task_struct * p) +int copy_thread_tls(unsigned long clone_flags, unsigned long sp, + unsigned long arg, struct task_struct * p, unsigned long tls) { void (*handler)(void); int kthread = current->flags & PF_KTHREAD; @@ -188,7 +188,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, * Set a new TLS for the child thread? */ if (clone_flags & CLONE_SETTLS) - ret = arch_copy_tls(p); + ret = arch_set_tls(p, tls); } return ret; diff --git a/arch/x86/um/tls_32.c b/arch/x86/um/tls_32.c index 5bd949da7a4a..ac8eee093f9c 100644 --- a/arch/x86/um/tls_32.c +++ b/arch/x86/um/tls_32.c @@ -215,14 +215,12 @@ static int set_tls_entry(struct task_struct* task, struct user_desc *info, return 0; } -int arch_copy_tls(struct task_struct *new) +int arch_set_tls(struct task_struct *new, unsigned long tls) { struct user_desc info; int idx, ret = -EFAULT; - if (copy_from_user(&info, - (void __user *) UPT_SI(&new->thread.regs.regs), - sizeof(info))) + if (copy_from_user(&info, (void __user *) tls, sizeof(info))) goto out; ret = -EINVAL; diff --git a/arch/x86/um/tls_64.c b/arch/x86/um/tls_64.c index 3a621e0d3925..ebd3855d9b13 100644 --- a/arch/x86/um/tls_64.c +++ b/arch/x86/um/tls_64.c @@ -6,14 +6,13 @@ void clear_flushed_tls(struct task_struct *task) { } -int arch_copy_tls(struct task_struct *t) +int arch_set_tls(struct task_struct *t, unsigned long tls) { /* * If CLONE_SETTLS is set, we need to save the thread id - * (which is argument 5, child_tid, of clone) so it can be set - * during context switches. + * so it can be set during context switches. */ - t->thread.arch.fs = t->thread.regs.regs.gp[R8 / sizeof(long)]; + t->thread.arch.fs = tls; return 0; }