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| author |   Al Viro <viro@zeniv.linux.org.uk> | 2012-10-23 23:32:21 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-10-25 09:41:10 -0400 |
| commit | 008f17948725c112a3422f72ed57fdc980e146a8 (patch) | |
| tree | 0346d52f24b01c111835055b35d82f0ba8370bbf /arch/tile/kernel/process.c | |
| parent | arch/tile: eliminate pt_regs trampolines for syscalls (diff) | |
| download | linux-dev-008f17948725c112a3422f72ed57fdc980e146a8.tar.xz linux-dev-008f17948725c112a3422f72ed57fdc980e146a8.zip | |
tile: sanitize copy_thread()
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/tile/kernel/process.c')
| -rw-r--r-- | arch/tile/kernel/process.c | 24 |
1 files changed, 11 insertions, 13 deletions
diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c index 6e7fb4e41f1c..1c20029d2f5a 100644 --- a/arch/tile/kernel/process.c +++ b/arch/tile/kernel/process.c @@ -158,7 +158,7 @@ static void save_arch_state(struct thread_struct *t); int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg, - struct task_struct *p, struct pt_regs *regs) + struct task_struct *p, struct pt_regs *unused) { struct pt_regs *childregs = task_pt_regs(p); unsigned long ksp; @@ -184,7 +184,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, /* Record the pid of the task that created this one. */ p->thread.creator_pid = current->pid; - if (unlikely(!regs)) { + if (unlikely(p->flags & PF_KTHREAD)) { /* kernel thread */ memset(childregs, 0, sizeof(struct pt_regs)); memset(&callee_regs[2], 0, @@ -208,25 +208,26 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, */ task_thread_info(p)->step_state = NULL; - /* Save user stack top pointer so we can ID the stack vm area later. */ - p->thread.usp0 = sp; - /* * Copy the registers onto the kernel stack so the * return-from-interrupt code will reload it into registers. */ - *childregs = *regs; + *childregs = *current_pt_regs(); childregs->regs[0] = 0; /* return value is zero */ - childregs->sp = sp; /* override with new user stack pointer */ - memcpy(callee_regs, ®s->regs[CALLEE_SAVED_FIRST_REG], + if (sp) + childregs->sp = sp; /* override with new user stack pointer */ + memcpy(callee_regs, &childregs->regs[CALLEE_SAVED_FIRST_REG], CALLEE_SAVED_REGS_COUNT * sizeof(unsigned long)); + /* Save user stack top pointer so we can ID the stack vm area later. */ + p->thread.usp0 = childregs->sp; + /* * If CLONE_SETTLS is set, set "tp" in the new task to "r4", * which is passed in as arg #5 to sys_clone(). */ if (clone_flags & CLONE_SETTLS) - childregs->tp = regs->regs[4]; + childregs->tp = childregs->regs[4]; #if CHIP_HAS_TILE_DMA() @@ -587,10 +588,7 @@ int do_work_pending(struct pt_regs *regs, u32 thread_info_flags) SYSCALL_DEFINE4(clone, unsigned long, clone_flags, unsigned long, newsp, void __user *, parent_tidptr, void __user *, child_tidptr) { - struct pt_regs *regs = current_pt_regs(); - if (!newsp) - newsp = regs->sp; - return do_fork(clone_flags, newsp, regs, 0, + return do_fork(clone_flags, newsp, current_pt_regs(), 0, parent_tidptr, child_tidptr); } |