| From 0039dbe9891cfdf2c0d04691f83c2f342993dfd7 Mon Sep 17 00:00:00 2001 |
| From: Michael Jeanson <mjeanson@efficios.com> |
| Date: Wed, 9 Jan 2019 14:59:15 -0500 |
| Subject: [PATCH 5/9] Fix: Remove 'type' argument from access_ok() function |
| (v5.0) |
| |
| See upstream commit : |
| |
| commit 96d4f267e40f9509e8a66e2b39e8b95655617693 |
| Author: Linus Torvalds <torvalds@linux-foundation.org> |
| Date: Thu Jan 3 18:57:57 2019 -0800 |
| |
| Remove 'type' argument from access_ok() function |
| |
| Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument |
| of the user address range verification function since we got rid of the |
| old racy i386-only code to walk page tables by hand. |
| |
| It existed because the original 80386 would not honor the write protect |
| bit when in kernel mode, so you had to do COW by hand before doing any |
| user access. But we haven't supported that in a long time, and these |
| days the 'type' argument is a purely historical artifact. |
| |
| A discussion about extending 'user_access_begin()' to do the range |
| checking resulted this patch, because there is no way we're going to |
| move the old VERIFY_xyz interface to that model. And it's best done at |
| the end of the merge window when I've done most of my merges, so let's |
| just get this done once and for all. |
| |
| This patch was mostly done with a sed-script, with manual fix-ups for |
| the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. |
| |
| There were a couple of notable cases: |
| |
| - csky still had the old "verify_area()" name as an alias. |
| |
| - the iter_iov code had magical hardcoded knowledge of the actual |
| values of VERIFY_{READ,WRITE} (not that they mattered, since nothing |
| really used it) |
| |
| - microblaze used the type argument for a debug printout |
| |
| but other than those oddities this should be a total no-op patch. |
| |
| I tried to fix up all architectures, did fairly extensive grepping for |
| access_ok() uses, and the changes are trivial, but I may have missed |
| something. Any missed conversion should be trivially fixable, though. |
| |
| Signed-off-by: Michael Jeanson <mjeanson@efficios.com> |
| Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| |
| Upstream-Status: backport https://github.com/lttng/lttng-modules/commit/0039dbe9891cfdf2c0d04691f83c2f342993dfd7 |
| |
| Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com> |
| --- |
| lib/ringbuffer/backend.h | 8 ++++---- |
| lib/ringbuffer/ring_buffer_iterator.c | 3 ++- |
| lttng-filter-interpreter.c | 4 ++-- |
| probes/lttng-probe-user.c | 3 ++- |
| wrapper/uaccess.h | 28 +++++++++++++++++++++++++++ |
| 5 files changed, 38 insertions(+), 8 deletions(-) |
| create mode 100644 wrapper/uaccess.h |
| |
| diff --git a/lib/ringbuffer/backend.h b/lib/ringbuffer/backend.h |
| index 0b75de8..3f8c108 100644 |
| --- a/lib/ringbuffer/backend.h |
| +++ b/lib/ringbuffer/backend.h |
| @@ -34,7 +34,7 @@ |
| #include <linux/list.h> |
| #include <linux/fs.h> |
| #include <linux/mm.h> |
| -#include <linux/uaccess.h> |
| +#include <wrapper/uaccess.h> |
| |
| /* Internal helpers */ |
| #include <wrapper/ringbuffer/backend_internal.h> |
| @@ -302,7 +302,7 @@ void lib_ring_buffer_copy_from_user_inatomic(const struct lib_ring_buffer_config |
| |
| set_fs(KERNEL_DS); |
| pagefault_disable(); |
| - if (unlikely(!access_ok(VERIFY_READ, src, len))) |
| + if (unlikely(!lttng_access_ok(VERIFY_READ, src, len))) |
| goto fill_buffer; |
| |
| if (likely(pagecpy == len)) { |
| @@ -372,7 +372,7 @@ void lib_ring_buffer_strcpy_from_user_inatomic(const struct lib_ring_buffer_conf |
| |
| set_fs(KERNEL_DS); |
| pagefault_disable(); |
| - if (unlikely(!access_ok(VERIFY_READ, src, len))) |
| + if (unlikely(!lttng_access_ok(VERIFY_READ, src, len))) |
| goto fill_buffer; |
| |
| if (likely(pagecpy == len)) { |
| @@ -462,7 +462,7 @@ unsigned long lib_ring_buffer_copy_from_user_check_nofault(void *dest, |
| unsigned long ret; |
| mm_segment_t old_fs; |
| |
| - if (!access_ok(VERIFY_READ, src, len)) |
| + if (!lttng_access_ok(VERIFY_READ, src, len)) |
| return 1; |
| old_fs = get_fs(); |
| set_fs(KERNEL_DS); |
| diff --git a/lib/ringbuffer/ring_buffer_iterator.c b/lib/ringbuffer/ring_buffer_iterator.c |
| index 61eaa5b..9645946 100644 |
| --- a/lib/ringbuffer/ring_buffer_iterator.c |
| +++ b/lib/ringbuffer/ring_buffer_iterator.c |
| @@ -27,6 +27,7 @@ |
| |
| #include <wrapper/ringbuffer/iterator.h> |
| #include <wrapper/file.h> |
| +#include <wrapper/uaccess.h> |
| #include <linux/jiffies.h> |
| #include <linux/delay.h> |
| #include <linux/module.h> |
| @@ -621,7 +622,7 @@ ssize_t channel_ring_buffer_file_read(struct file *filp, |
| ssize_t len; |
| |
| might_sleep(); |
| - if (!access_ok(VERIFY_WRITE, user_buf, count)) |
| + if (!lttng_access_ok(VERIFY_WRITE, user_buf, count)) |
| return -EFAULT; |
| |
| /* Finish copy of previous record */ |
| diff --git a/lttng-filter-interpreter.c b/lttng-filter-interpreter.c |
| index e131462..bee2918 100644 |
| --- a/lttng-filter-interpreter.c |
| +++ b/lttng-filter-interpreter.c |
| @@ -24,7 +24,7 @@ |
| * SOFTWARE. |
| */ |
| |
| -#include <linux/uaccess.h> |
| +#include <wrapper/uaccess.h> |
| #include <wrapper/frame.h> |
| #include <wrapper/types.h> |
| |
| @@ -46,7 +46,7 @@ char get_char(struct estack_entry *reg, size_t offset) |
| char c; |
| |
| /* Handle invalid access as end of string. */ |
| - if (unlikely(!access_ok(VERIFY_READ, |
| + if (unlikely(!lttng_access_ok(VERIFY_READ, |
| reg->u.s.user_str + offset, |
| sizeof(c)))) |
| return '\0'; |
| diff --git a/probes/lttng-probe-user.c b/probes/lttng-probe-user.c |
| index 099a66b..ed566dd 100644 |
| --- a/probes/lttng-probe-user.c |
| +++ b/probes/lttng-probe-user.c |
| @@ -20,6 +20,7 @@ |
| |
| #include <linux/uaccess.h> |
| #include <linux/module.h> |
| +#include <wrapper/uaccess.h> |
| #include <probes/lttng-probe-user.h> |
| |
| /* |
| @@ -43,7 +44,7 @@ long lttng_strlen_user_inatomic(const char *addr) |
| char v; |
| unsigned long ret; |
| |
| - if (unlikely(!access_ok(VERIFY_READ, |
| + if (unlikely(!lttng_access_ok(VERIFY_READ, |
| (__force const char __user *) addr, |
| sizeof(v)))) |
| break; |
| diff --git a/wrapper/uaccess.h b/wrapper/uaccess.h |
| new file mode 100644 |
| index 0000000..c56427c |
| --- /dev/null |
| +++ b/wrapper/uaccess.h |
| @@ -0,0 +1,28 @@ |
| +/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1) |
| + * |
| + * wrapper/uaccess.h |
| + * |
| + * wrapper around linux/uaccess.h. |
| + * |
| + * Copyright (C) 2019 Michael Jeanson <mjeanson@efficios.com> |
| + */ |
| + |
| +#ifndef _LTTNG_WRAPPER_UACCESS_H |
| +#define _LTTNG_WRAPPER_UACCESS_H |
| + |
| +#include <linux/uaccess.h> |
| +#include <lttng-kernel-version.h> |
| + |
| +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,0,0)) |
| + |
| +#define VERIFY_READ 0 |
| +#define VERIFY_WRITE 1 |
| +#define lttng_access_ok(type, addr, size) access_ok(addr, size) |
| + |
| +#else /* LINUX_VERSION_CODE >= KERNEL_VERSION(5,0,0) */ |
| + |
| +#define lttng_access_ok(type, addr, size) access_ok(type, addr, size) |
| + |
| +#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(5,0,0) */ |
| + |
| +#endif /* _LTTNG_WRAPPER_UACCESS_H */ |
| -- |
| 2.19.1 |
| |