diff options
Diffstat (limited to 'runtime')
| -rw-r--r-- | runtime/access_process_vm.h | 54 | ||||
| -rw-r--r-- | runtime/addr-map.c | 4 | ||||
| -rw-r--r-- | runtime/itrace.c | 54 | ||||
| -rw-r--r-- | runtime/print.c | 12 | ||||
| -rw-r--r-- | runtime/runtime.h | 28 |
5 files changed, 97 insertions, 55 deletions
diff --git a/runtime/access_process_vm.h b/runtime/access_process_vm.h new file mode 100644 index 00000000..70489d48 --- /dev/null +++ b/runtime/access_process_vm.h @@ -0,0 +1,54 @@ +/* + * The kernel's access_process_vm is not exported in kernel.org kernels, although + * some distros export it on some architectures. To workaround this inconsistency, + * we copied and pasted it here. Fortunately, everything it calls is exported. + */ +#include <linux/pagemap.h> +#include <asm/cacheflush.h> +static int __access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) +{ + struct mm_struct *mm; + struct vm_area_struct *vma; + struct page *page; + void *old_buf = buf; + + mm = get_task_mm(tsk); + if (!mm) + return 0; + + down_read(&mm->mmap_sem); + /* ignore errors, just check how much was sucessfully transfered */ + while (len) { + int bytes, ret, offset; + void *maddr; + + ret = get_user_pages(tsk, mm, addr, 1, + write, 1, &page, &vma); + if (ret <= 0) + break; + + bytes = len; + offset = addr & (PAGE_SIZE-1); + if (bytes > PAGE_SIZE-offset) + bytes = PAGE_SIZE-offset; + + maddr = kmap(page); + if (write) { + copy_to_user_page(vma, page, addr, + maddr + offset, buf, bytes); + set_page_dirty_lock(page); + } else { + copy_from_user_page(vma, page, addr, + buf, maddr + offset, bytes); + } + kunmap(page); + page_cache_release(page); + len -= bytes; + buf += bytes; + addr += bytes; + } + up_read(&mm->mmap_sem); + mmput(mm); + + return buf - old_buf; +} diff --git a/runtime/addr-map.c b/runtime/addr-map.c index a9aa8d88..35de7a64 100644 --- a/runtime/addr-map.c +++ b/runtime/addr-map.c @@ -115,6 +115,10 @@ lookup_bad_addr(unsigned long addr, size_t size) return 1; #ifndef STP_PRIVILEGED + /* Unprivileged users must not access memory while the context + does not refer to their own process. */ + if (! is_myproc ()) + return 1; /* Unprivileged users must not access kernel space memory. */ if (addr + size > TASK_SIZE) return 1; diff --git a/runtime/itrace.c b/runtime/itrace.c index 6fe39db4..03e1e403 100644 --- a/runtime/itrace.c +++ b/runtime/itrace.c @@ -77,60 +77,8 @@ static struct itrace_info *create_itrace_info( struct task_struct *tsk, u32 step_flag, struct stap_itrace_probe *itrace_probe); -/* - * The kernel's access_process_vm is not exported in kernel.org kernels, although - * some distros export it on some architectures. To workaround this inconsistency, - * we copied and pasted it here. Fortunately, everything it calls is exported. - */ -#include <linux/pagemap.h> -#include <asm/cacheflush.h> -static int __access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) -{ - struct mm_struct *mm; - struct vm_area_struct *vma; - struct page *page; - void *old_buf = buf; - - mm = get_task_mm(tsk); - if (!mm) - return 0; - - down_read(&mm->mmap_sem); - /* ignore errors, just check how much was sucessfully transfered */ - while (len) { - int bytes, ret, offset; - void *maddr; - ret = get_user_pages(tsk, mm, addr, 1, - write, 1, &page, &vma); - if (ret <= 0) - break; - - bytes = len; - offset = addr & (PAGE_SIZE-1); - if (bytes > PAGE_SIZE-offset) - bytes = PAGE_SIZE-offset; - - maddr = kmap(page); - if (write) { - copy_to_user_page(vma, page, addr, - maddr + offset, buf, bytes); - set_page_dirty_lock(page); - } else { - copy_from_user_page(vma, page, addr, - buf, maddr + offset, bytes); - } - kunmap(page); - page_cache_release(page); - len -= bytes; - buf += bytes; - addr += bytes; - } - up_read(&mm->mmap_sem); - mmput(mm); - - return buf - old_buf; -} +/* Note: __access_process_vm moved to access_process_vm.h */ #ifdef UTRACE_ORIG_VERSION static u32 usr_itrace_report_quiesce(struct utrace_attached_engine *engine, diff --git a/runtime/print.c b/runtime/print.c index 945f7a72..335403fb 100644 --- a/runtime/print.c +++ b/runtime/print.c @@ -225,7 +225,11 @@ static void _stp_print_kernel_info(char *vstr, int ctx, int num_probes) #ifdef DEBUG_MEM "+alloc" #endif - ", probes: %d\n", + ", probes: %d" +#ifndef STP_PRIVILEGED + ", unpriv-uid: %d" +#endif + "\n", THIS_MODULE->name, vstr, #ifndef STAPCONF_GRSECURITY @@ -242,7 +246,11 @@ static void _stp_print_kernel_info(char *vstr, int ctx, int num_probes) #ifdef DEBUG_MEM _stp_allocated_memory - _stp_allocated_net_memory, #endif - num_probes); + num_probes +#ifndef STP_PRIVILEGED + , _stp_uid +#endif + ); } /** @} */ diff --git a/runtime/runtime.h b/runtime/runtime.h index 064ded7b..7087d435 100644 --- a/runtime/runtime.h +++ b/runtime/runtime.h @@ -54,6 +54,32 @@ static void _stp_warn (const char *fmt, ...) __attribute__ ((format (printf, 1, static void _stp_exit(void); + + +/* unprivileged user support */ + +#ifdef STAPCONF_TASK_UID +#define STP_CURRENT_EUID (current->euid) +#else +#define STP_CURRENT_EUID (task_euid(current)) +#endif + +#define is_myproc() (STP_CURRENT_EUID == _stp_uid) + +#ifndef STP_PRIVILEGED +#define assert_is_myproc() do { \ + if (! is_myproc()) { \ + snprintf (CONTEXT->error_buffer, MAXSTRINGLEN, "semi-privileged tapset function called without is_myproc checking for pid %d (euid %d)", \ + current->tgid, STP_CURRENT_EUID); \ + CONTEXT->last_error = CONTEXT->error_buffer; \ + goto out; \ + } } while (0) +#else +#define assert_is_myproc() do {} while (0) +#endif + + + #include "debug.h" /* atomic globals */ @@ -106,6 +132,8 @@ static struct #endif #include "addr-map.c" + + /* Support functions for int64_t module parameters. */ static int param_set_int64_t(const char *val, struct kernel_param *kp) { |