From ab286b21aa95c9c46421c59a96bf7745ba2866ca Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 3 Sep 2012 03:24:18 -0400 Subject: um: take cleaning singlestep to start_thread() ... assuming it's needed to be done at all Signed-off-by: Al Viro --- arch/um/kernel/exec.c | 24 +++++------------------- 1 file changed, 5 insertions(+), 19 deletions(-) (limited to 'arch/um') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 6cade9366364..4cab0c78684b 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -41,32 +41,18 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) { PT_REGS_IP(regs) = eip; PT_REGS_SP(regs) = esp; -} -EXPORT_SYMBOL(start_thread); - -static long execve1(const char *file, - const char __user *const __user *argv, - const char __user *const __user *env) -{ - long error; - - error = do_execve(file, argv, env, ¤t->thread.regs); - if (error == 0) { - task_lock(current); - current->ptrace &= ~PT_DTRACE; + current->ptrace &= ~PT_DTRACE; #ifdef SUBARCH_EXECVE1 - SUBARCH_EXECVE1(¤t->thread.regs.regs); + SUBARCH_EXECVE1(regs->regs); #endif - task_unlock(current); - } - return error; } +EXPORT_SYMBOL(start_thread); long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env) { long err; - err = execve1(file, argv, env); + err = do_execve(file, argv, env, ¤t->thread.regs); if (!err) UML_LONGJMP(current->thread.exec_buf, 1); return err; @@ -81,7 +67,7 @@ long sys_execve(const char __user *file, const char __user *const __user *argv, filename = getname(file); error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; - error = execve1(filename, argv, env); + error = do_execve(filename, argv, env, ¤t->thread.regs); putname(filename); out: return error; -- cgit v1.2.3 From 344569aef36970f3b08cbd45cd19a941edc8066f Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 5 Sep 2012 23:20:33 -0400 Subject: um: don't leak floating point state and segment registers on execve() Signed-off-by: Al Viro --- arch/um/kernel/exec.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/um') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 4cab0c78684b..8c82786da823 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -39,6 +39,7 @@ void flush_thread(void) void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) { + get_safe_registers(regs->regs.gp, regs->regs.fp); PT_REGS_IP(regs) = eip; PT_REGS_SP(regs) = esp; current->ptrace &= ~PT_DTRACE; -- cgit v1.2.3 From 8e2c85aa6c7a158d967db75931db7f13d20d31f4 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 6 Sep 2012 13:39:47 -0400 Subject: um: let signal_delivered() do SIGTRAP on singlestepping into handler ... rather than duplicating that in sigframe setup code (and doing that inconsistently, at that) Signed-off-by: Al Viro --- arch/um/kernel/signal.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/um') diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c index 7362d58efc29..cc9c2350e417 100644 --- a/arch/um/kernel/signal.c +++ b/arch/um/kernel/signal.c @@ -22,9 +22,13 @@ static void handle_signal(struct pt_regs *regs, unsigned long signr, struct k_sigaction *ka, siginfo_t *info) { sigset_t *oldset = sigmask_to_save(); + int singlestep = 0; unsigned long sp; int err; + if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED)) + singlestep = 1; + /* Did we come from a system call? */ if (PT_REGS_SYSCALL_NR(regs) >= 0) { /* If so, check system call restarting.. */ @@ -61,7 +65,7 @@ static void handle_signal(struct pt_regs *regs, unsigned long signr, if (err) force_sigsegv(signr, current); else - signal_delivered(signr, info, ka, regs, 0); + signal_delivered(signr, info, ka, regs, singlestep); } static int kern_do_signal(struct pt_regs *regs) -- cgit v1.2.3 From a4d94ff8aa864c05b33c2de1f8c5d0176d7a4b63 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 20 Sep 2012 09:28:25 -0400 Subject: um: kill thread->forking we only use that to tell copy_thread() done by syscall from that done by kernel_thread(). However, it's easier to do simply by checking PF_KTHREAD in thread flags. Merge sys_clone() guts for 32bit and 64bit, while we are at it... Signed-off-by: Al Viro --- arch/um/include/asm/processor-generic.h | 9 --------- arch/um/kernel/process.c | 8 ++++---- arch/um/kernel/syscall.c | 24 ++++++++++++------------ 3 files changed, 16 insertions(+), 25 deletions(-) (limited to 'arch/um') diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h index 69f1c57a8d0d..33a6a2423bd2 100644 --- a/arch/um/include/asm/processor-generic.h +++ b/arch/um/include/asm/processor-generic.h @@ -20,14 +20,6 @@ struct mm_struct; struct thread_struct { struct task_struct *saved_task; - /* - * This flag is set to 1 before calling do_fork (and analyzed in - * copy_thread) to mark that we are begin called from userspace (fork / - * vfork / clone), and reset to 0 after. It is left to 0 when called - * from kernelspace (i.e. kernel_thread() or fork_idle(), - * as of 2.6.11). - */ - int forking; struct pt_regs regs; int singlestep_syscall; void *fault_addr; @@ -58,7 +50,6 @@ struct thread_struct { #define INIT_THREAD \ { \ - .forking = 0, \ .regs = EMPTY_REGS, \ .fault_addr = NULL, \ .prev_sched = NULL, \ diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index 57fc7028714a..c5f5afa50745 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -181,11 +181,12 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, struct pt_regs *regs) { void (*handler)(void); + int kthread = current->flags & PF_KTHREAD; int ret = 0; p->thread = (struct thread_struct) INIT_THREAD; - if (current->thread.forking) { + if (!kthread) { memcpy(&p->thread.regs.regs, ®s->regs, sizeof(p->thread.regs.regs)); PT_REGS_SET_SYSCALL_RETURN(&p->thread.regs, 0); @@ -195,8 +196,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, handler = fork_handler; arch_copy_thread(¤t->thread.arch, &p->thread.arch); - } - else { + } else { get_safe_registers(p->thread.regs.regs.gp, p->thread.regs.regs.fp); p->thread.request.u.thread = current->thread.request.u.thread; handler = new_thread_handler; @@ -204,7 +204,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, new_thread(task_stack_page(p), &p->thread.switch_buf, handler); - if (current->thread.forking) { + if (!kthread) { clear_flushed_tls(p); /* diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c index f958cb876ee3..a4c6d8eee74c 100644 --- a/arch/um/kernel/syscall.c +++ b/arch/um/kernel/syscall.c @@ -17,25 +17,25 @@ long sys_fork(void) { - long ret; - - current->thread.forking = 1; - ret = do_fork(SIGCHLD, UPT_SP(¤t->thread.regs.regs), + return do_fork(SIGCHLD, UPT_SP(¤t->thread.regs.regs), ¤t->thread.regs, 0, NULL, NULL); - current->thread.forking = 0; - return ret; } long sys_vfork(void) { - long ret; - - current->thread.forking = 1; - ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, UPT_SP(¤t->thread.regs.regs), ¤t->thread.regs, 0, NULL, NULL); - current->thread.forking = 0; - return ret; +} + +long sys_clone(unsigned long clone_flags, unsigned long newsp, + void __user *parent_tid, void __user *child_tid) +{ + if (!newsp) + newsp = UPT_SP(¤t->thread.regs.regs); + + return do_fork(clone_flags, newsp, ¤t->thread.regs, 0, parent_tid, + child_tid); } long old_mmap(unsigned long addr, unsigned long len, -- cgit v1.2.3 From 6783eaa2e1253fbcbe2c2f6bb4c843abf1343caf Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 2 Aug 2012 23:05:11 +0400 Subject: x86, um/x86: switch to generic sys_execve and kernel_execve 32bit wrapper is lost on that; 64bit one is *not*, since we need to arrange for full pt_regs on stack when we call sys_execve() and we need to load callee-saved ones from there afterwards. Signed-off-by: Al Viro --- arch/um/kernel/exec.c | 25 ++----------------------- arch/um/kernel/internal.h | 1 - arch/um/kernel/syscall.c | 17 ----------------- 3 files changed, 2 insertions(+), 41 deletions(-) delete mode 100644 arch/um/kernel/internal.h (limited to 'arch/um') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 8c82786da823..e427301f55d6 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -16,7 +16,6 @@ #include "mem_user.h" #include "skas.h" #include "os.h" -#include "internal.h" void flush_thread(void) { @@ -49,27 +48,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) } EXPORT_SYMBOL(start_thread); -long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env) +void __noreturn ret_from_kernel_execve(struct pt_regs *unused) { - long err; - - err = do_execve(file, argv, env, ¤t->thread.regs); - if (!err) - UML_LONGJMP(current->thread.exec_buf, 1); - return err; -} - -long sys_execve(const char __user *file, const char __user *const __user *argv, - const char __user *const __user *env) -{ - long error; - char *filename; - - filename = getname(file); - error = PTR_ERR(filename); - if (IS_ERR(filename)) goto out; - error = do_execve(filename, argv, env, ¤t->thread.regs); - putname(filename); - out: - return error; + UML_LONGJMP(current->thread.exec_buf, 1); } diff --git a/arch/um/kernel/internal.h b/arch/um/kernel/internal.h deleted file mode 100644 index 5bf97db24a04..000000000000 --- a/arch/um/kernel/internal.h +++ /dev/null @@ -1 +0,0 @@ -extern long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env); diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c index a4c6d8eee74c..a5639c472772 100644 --- a/arch/um/kernel/syscall.c +++ b/arch/um/kernel/syscall.c @@ -13,7 +13,6 @@ #include "asm/mman.h" #include "asm/uaccess.h" #include "asm/unistd.h" -#include "internal.h" long sys_fork(void) { @@ -50,19 +49,3 @@ long old_mmap(unsigned long addr, unsigned long len, out: return err; } - -int kernel_execve(const char *filename, - const char *const argv[], - const char *const envp[]) -{ - mm_segment_t fs; - int ret; - - fs = get_fs(); - set_fs(KERNEL_DS); - ret = um_execve(filename, (const char __user *const __user *)argv, - (const char __user *const __user *) envp); - set_fs(fs); - - return ret; -} -- cgit v1.2.3 From 1f02ab4a237086095bd584f3446da307ac2d02e6 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 21 Sep 2012 20:32:29 -0400 Subject: um: switch to generic kernel_thread() Signed-off-by: Al Viro --- arch/um/include/asm/processor-generic.h | 2 -- arch/um/kernel/process.c | 17 +++-------------- 2 files changed, 3 insertions(+), 16 deletions(-) (limited to 'arch/um') diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h index 33a6a2423bd2..5d9ab0c4f488 100644 --- a/arch/um/include/asm/processor-generic.h +++ b/arch/um/include/asm/processor-generic.h @@ -63,8 +63,6 @@ static inline void release_thread(struct task_struct *task) { } -extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags); - extern unsigned long thread_saved_pc(struct task_struct *t); static inline void mm_copy_segments(struct mm_struct *from_mm, diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index c5f5afa50745..a1b50add48a2 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -69,18 +69,6 @@ unsigned long alloc_stack(int order, int atomic) return page; } -int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) -{ - int pid; - - current->thread.request.u.thread.proc = fn; - current->thread.request.u.thread.arg = arg; - pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, - ¤t->thread.regs, 0, NULL, NULL); - return pid; -} -EXPORT_SYMBOL(kernel_thread); - static inline void set_current(struct task_struct *task) { cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task) @@ -177,7 +165,7 @@ void fork_handler(void) } int copy_thread(unsigned long clone_flags, unsigned long sp, - unsigned long stack_top, struct task_struct * p, + unsigned long arg, struct task_struct * p, struct pt_regs *regs) { void (*handler)(void); @@ -198,7 +186,8 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, arch_copy_thread(¤t->thread.arch, &p->thread.arch); } else { get_safe_registers(p->thread.regs.regs.gp, p->thread.regs.regs.fp); - p->thread.request.u.thread = current->thread.request.u.thread; + p->thread.request.u.thread.proc = (int (*)(void *))sp; + p->thread.request.u.thread.arg = (void *)arg; handler = new_thread_handler; } -- cgit v1.2.3