diff --git a/arch/alpha/kernel/ptrace.c b/arch/alpha/kernel/ptrace.c index 86d835157b546..292e6cae1d101 100644 --- a/arch/alpha/kernel/ptrace.c +++ b/arch/alpha/kernel/ptrace.c @@ -281,7 +281,7 @@ long arch_ptrace(struct task_struct *child, long request, /* When I and D space are separate, these will need to be fixed. */ case PTRACE_PEEKTEXT: /* read word at location addr. */ case PTRACE_PEEKDATA: - copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); + copied = ptrace_access_vm(child, addr, &tmp, sizeof(tmp), 0); ret = -EIO; if (copied != sizeof(tmp)) break; diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c index 8b8fe671b1a6d..7d8ece6a93fb5 100644 --- a/arch/blackfin/kernel/ptrace.c +++ b/arch/blackfin/kernel/ptrace.c @@ -270,7 +270,7 @@ long arch_ptrace(struct task_struct *child, long request, switch (bfin_mem_access_type(addr, to_copy)) { case BFIN_MEM_ACCESS_CORE: case BFIN_MEM_ACCESS_CORE_ONLY: - copied = access_process_vm(child, addr, &tmp, + copied = ptrace_access_vm(child, addr, &tmp, to_copy, 0); if (copied) break; @@ -323,7 +323,7 @@ long arch_ptrace(struct task_struct *child, long request, switch (bfin_mem_access_type(addr, to_copy)) { case BFIN_MEM_ACCESS_CORE: case BFIN_MEM_ACCESS_CORE_ONLY: - copied = access_process_vm(child, addr, &data, + copied = ptrace_access_vm(child, addr, &data, to_copy, 1); break; case BFIN_MEM_ACCESS_DMA: diff --git a/arch/cris/arch-v32/kernel/ptrace.c b/arch/cris/arch-v32/kernel/ptrace.c index f085229cf870b..04251c6cb5f9d 100644 --- a/arch/cris/arch-v32/kernel/ptrace.c +++ b/arch/cris/arch-v32/kernel/ptrace.c @@ -147,7 +147,7 @@ long arch_ptrace(struct task_struct *child, long request, /* The trampoline page is globally mapped, no page table to traverse.*/ tmp = *(unsigned long*)addr; } else { - copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); + copied = ptrace_access_vm(child, addr, &tmp, sizeof(tmp), 0); if (copied != sizeof(tmp)) break; diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c index b7a5fffe0924e..c218249c4792b 100644 --- a/arch/ia64/kernel/ptrace.c +++ b/arch/ia64/kernel/ptrace.c @@ -1156,7 +1156,7 @@ arch_ptrace (struct task_struct *child, long request, case PTRACE_PEEKTEXT: case PTRACE_PEEKDATA: /* read word at location addr */ - if (access_process_vm(child, addr, &data, sizeof(data), 0) + if (ptrace_access_vm(child, addr, &data, sizeof(data), 0) != sizeof(data)) return -EIO; /* ensure return value is not mistaken for error code */ diff --git a/arch/mips/kernel/ptrace32.c b/arch/mips/kernel/ptrace32.c index a83fb730b387a..fdd26c104c6ca 100644 --- a/arch/mips/kernel/ptrace32.c +++ b/arch/mips/kernel/ptrace32.c @@ -69,7 +69,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0) break; - copied = access_process_vm(child, (u64)addrOthers, &tmp, + copied = ptrace_access_vm(child, (u64)addrOthers, &tmp, sizeof(tmp), 0); if (copied != sizeof(tmp)) break; @@ -178,7 +178,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0) break; ret = 0; - if (access_process_vm(child, (u64)addrOthers, &data, + if (ptrace_access_vm(child, (u64)addrOthers, &data, sizeof(data), 1) == sizeof(data)) break; ret = -EIO; diff --git a/arch/powerpc/kernel/ptrace32.c b/arch/powerpc/kernel/ptrace32.c index f52b7db327c80..2e4f01dc9d643 100644 --- a/arch/powerpc/kernel/ptrace32.c +++ b/arch/powerpc/kernel/ptrace32.c @@ -73,7 +73,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, if (get_user(addrOthers, (u32 __user * __user *)addr) != 0) break; - copied = access_process_vm(child, (u64)addrOthers, &tmp, + copied = ptrace_access_vm(child, (u64)addrOthers, &tmp, sizeof(tmp), 0); if (copied != sizeof(tmp)) break; @@ -178,7 +178,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, if (get_user(addrOthers, (u32 __user * __user *)addr) != 0) break; ret = 0; - if (access_process_vm(child, (u64)addrOthers, &tmp, + if (ptrace_access_vm(child, (u64)addrOthers, &tmp, sizeof(tmp), 1) == sizeof(tmp)) break; ret = -EIO; diff --git a/include/linux/mm.h b/include/linux/mm.h index 35f8b59b37a78..65a4dc2da9de4 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1209,6 +1209,8 @@ static inline int fixup_user_fault(struct task_struct *tsk, extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, void *buf, int len, int write); +extern int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, + unsigned long addr, void *buf, int len, int write); long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index b9b35c4d687b8..8e81197a28dd6 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -8,6 +8,9 @@ #include /* For task_active_pid_ns. */ #include +extern int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, + void *buf, int len, int write); + /* * Ptrace flags * diff --git a/kernel/ptrace.c b/kernel/ptrace.c index b48bb2fef8c93..630bd8abaab1a 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -27,6 +27,35 @@ #include #include +/* + * Access another process' address space via ptrace. + * Source/target buffer must be kernel space, + * Do not walk the page table directly, use get_user_pages + */ +int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, + void *buf, int len, int write) +{ + struct mm_struct *mm; + int ret; + + mm = get_task_mm(tsk); + if (!mm) + return 0; + + if (!tsk->ptrace || + (current != tsk->parent) || + ((get_dumpable(mm) != SUID_DUMP_USER) && + !ptracer_capable(tsk, mm->user_ns))) { + mmput(mm); + return 0; + } + + ret = __access_remote_vm(tsk, mm, addr, buf, len, write); + mmput(mm); + + return ret; +} + static int ptrace_trapping_sleep_fn(void *flags) { @@ -558,7 +587,8 @@ int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst int this_len, retval; this_len = (len > sizeof(buf)) ? sizeof(buf) : len; - retval = access_process_vm(tsk, src, buf, this_len, 0); + retval = ptrace_access_vm(tsk, src, buf, this_len, 0); + if (!retval) { if (copied) break; @@ -585,7 +615,7 @@ int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long ds this_len = (len > sizeof(buf)) ? sizeof(buf) : len; if (copy_from_user(buf, src, this_len)) return -EFAULT; - retval = access_process_vm(tsk, dst, buf, this_len, 1); + retval = ptrace_access_vm(tsk, dst, buf, this_len, 1); if (!retval) { if (copied) break; @@ -1130,7 +1160,7 @@ int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr, unsigned long tmp; int copied; - copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0); + copied = ptrace_access_vm(tsk, addr, &tmp, sizeof(tmp), 0); if (copied != sizeof(tmp)) return -EIO; return put_user(tmp, (unsigned long __user *)data); @@ -1141,7 +1171,7 @@ int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr, { int copied; - copied = access_process_vm(tsk, addr, &data, sizeof(data), 1); + copied = ptrace_access_vm(tsk, addr, &data, sizeof(data), 1); return (copied == sizeof(data)) ? 0 : -EIO; } @@ -1159,7 +1189,7 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request, switch (request) { case PTRACE_PEEKTEXT: case PTRACE_PEEKDATA: - ret = access_process_vm(child, addr, &word, sizeof(word), 0); + ret = ptrace_access_vm(child, addr, &word, sizeof(word), 0); if (ret != sizeof(word)) ret = -EIO; else @@ -1168,7 +1198,7 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request, case PTRACE_POKETEXT: case PTRACE_POKEDATA: - ret = access_process_vm(child, addr, &data, sizeof(data), 1); + ret = ptrace_access_vm(child, addr, &data, sizeof(data), 1); ret = (ret != sizeof(data) ? -EIO : 0); break; diff --git a/mm/memory.c b/mm/memory.c index e1bde862d6d3f..4ab5b0c55f4ad 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3560,7 +3560,7 @@ EXPORT_SYMBOL_GPL(generic_access_phys); * Access another process' address space as given in mm. If non-NULL, use the * given task for page fault accounting. */ -static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, +int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, unsigned long addr, void *buf, int len, int write) { struct vm_area_struct *vma; diff --git a/mm/nommu.c b/mm/nommu.c index 53a59f41e2e55..7f2c901c555e4 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -2007,7 +2007,7 @@ int generic_file_remap_pages(struct vm_area_struct *vma, unsigned long addr, } EXPORT_SYMBOL(generic_file_remap_pages); -static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, +int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, unsigned long addr, void *buf, int len, int write) { struct vm_area_struct *vma;