diff options
Diffstat (limited to 'arch/um/kernel/trap_kern.c')
-rw-r--r-- | arch/um/kernel/trap_kern.c | 64 |
1 files changed, 21 insertions, 43 deletions
diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c index 47e766e..c20aef1 100644 --- a/arch/um/kernel/trap_kern.c +++ b/arch/um/kernel/trap_kern.c @@ -23,7 +23,6 @@ #include "kern.h" #include "chan_kern.h" #include "mconsole_kern.h" -#include "2_5compat.h" #include "mem.h" #include "mem_kern.h" @@ -48,7 +47,7 @@ int handle_page_fault(unsigned long address, unsigned long ip, goto good_area; else if(!(vma->vm_flags & VM_GROWSDOWN)) goto out; - else if(!ARCH_IS_STACKGROW(address)) + else if(is_user && !ARCH_IS_STACKGROW(address)) goto out; else if(expand_stack(vma, address)) goto out; @@ -57,10 +56,11 @@ int handle_page_fault(unsigned long address, unsigned long ip, *code_out = SEGV_ACCERR; if(is_write && !(vma->vm_flags & VM_WRITE)) goto out; + + if(!(vma->vm_flags & (VM_READ | VM_EXEC))) + goto out; + page = address & PAGE_MASK; - pgd = pgd_offset(mm, page); - pud = pud_offset(pgd, page); - pmd = pmd_offset(pud, page); do { survive: switch (handle_mm_fault(mm, vma, address, is_write)){ @@ -106,46 +106,24 @@ out_of_memory: goto out; } -LIST_HEAD(physmem_remappers); - -void register_remapper(struct remapper *info) -{ - list_add(&info->list, &physmem_remappers); -} - -static int check_remapped_addr(unsigned long address, int is_write) -{ - struct remapper *remapper; - struct list_head *ele; - __u64 offset; - int fd; - - fd = phys_mapping(__pa(address), &offset); - if(fd == -1) - return(0); - - list_for_each(ele, &physmem_remappers){ - remapper = list_entry(ele, struct remapper, list); - if((*remapper->proc)(fd, address, is_write, offset)) - return(1); - } - - return(0); -} - -unsigned long segv(unsigned long address, unsigned long ip, int is_write, - int is_user, void *sc) +/* + * We give a *copy* of the faultinfo in the regs to segv. + * This must be done, since nesting SEGVs could overwrite + * the info in the regs. A pointer to the info then would + * give us bad data! + */ +unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) { struct siginfo si; void *catcher; int err; + int is_write = FAULT_WRITE(fi); + unsigned long address = FAULT_ADDRESS(fi); if(!is_user && (address >= start_vm) && (address < end_vm)){ flush_tlb_kernel_vm(); return(0); } - else if(check_remapped_addr(address & PAGE_MASK, is_write)) - return(0); else if(current->mm == NULL) panic("Segfault with no mm"); err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); @@ -159,7 +137,7 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write, } else if(current->thread.fault_addr != NULL) panic("fault_addr set but no fault catcher"); - else if(arch_fixup(ip, sc)) + else if(!is_user && arch_fixup(ip, sc)) return(0); if(!is_user) @@ -171,6 +149,7 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write, si.si_errno = 0; si.si_code = BUS_ADRERR; si.si_addr = (void *)address; + current->thread.arch.faultinfo = fi; force_sig_info(SIGBUS, &si, current); } else if(err == -ENOMEM){ @@ -180,22 +159,20 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write, else { si.si_signo = SIGSEGV; si.si_addr = (void *) address; - current->thread.cr2 = address; - current->thread.err = is_write; + current->thread.arch.faultinfo = fi; force_sig_info(SIGSEGV, &si, current); } return(0); } -void bad_segv(unsigned long address, unsigned long ip, int is_write) +void bad_segv(struct faultinfo fi, unsigned long ip) { struct siginfo si; si.si_signo = SIGSEGV; si.si_code = SEGV_ACCERR; - si.si_addr = (void *) address; - current->thread.cr2 = address; - current->thread.err = is_write; + si.si_addr = (void *) FAULT_ADDRESS(fi); + current->thread.arch.faultinfo = fi; force_sig_info(SIGSEGV, &si, current); } @@ -204,6 +181,7 @@ void relay_signal(int sig, union uml_pt_regs *regs) if(arch_handle_signal(sig, regs)) return; if(!UPT_IS_USER(regs)) panic("Kernel mode signal %d", sig); + current->thread.arch.faultinfo = *UPT_FAULTINFO(regs); force_sig(sig, current); } |