From 96d4f267e40f9509e8a66e2b39e8b95655617693 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Thu, 3 Jan 2019 18:57:57 -0800 Subject: 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: Linus Torvalds --- arch/xtensa/include/asm/checksum.h | 2 +- arch/xtensa/include/asm/futex.h | 2 +- arch/xtensa/include/asm/uaccess.h | 10 +++++----- arch/xtensa/kernel/signal.c | 4 ++-- arch/xtensa/kernel/stacktrace.c | 2 +- 5 files changed, 10 insertions(+), 10 deletions(-) (limited to 'arch/xtensa') diff --git a/arch/xtensa/include/asm/checksum.h b/arch/xtensa/include/asm/checksum.h index 3ae74d7e074b..f302ef57973a 100644 --- a/arch/xtensa/include/asm/checksum.h +++ b/arch/xtensa/include/asm/checksum.h @@ -243,7 +243,7 @@ static __inline__ __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len, __wsum sum, int *err_ptr) { - if (access_ok(VERIFY_WRITE, dst, len)) + if (access_ok(dst, len)) return csum_partial_copy_generic(src,dst,len,sum,NULL,err_ptr); if (len) diff --git a/arch/xtensa/include/asm/futex.h b/arch/xtensa/include/asm/futex.h index fd0eef6b8e7c..505d09eff184 100644 --- a/arch/xtensa/include/asm/futex.h +++ b/arch/xtensa/include/asm/futex.h @@ -93,7 +93,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, { int ret = 0; - if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + if (!access_ok(uaddr, sizeof(u32))) return -EFAULT; #if !XCHAL_HAVE_S32C1I diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h index d11ef2939652..4b2480304bc3 100644 --- a/arch/xtensa/include/asm/uaccess.h +++ b/arch/xtensa/include/asm/uaccess.h @@ -42,7 +42,7 @@ #define __user_ok(addr, size) \ (((size) <= TASK_SIZE)&&((addr) <= TASK_SIZE-(size))) #define __access_ok(addr, size) (__kernel_ok || __user_ok((addr), (size))) -#define access_ok(type, addr, size) __access_ok((unsigned long)(addr), (size)) +#define access_ok(addr, size) __access_ok((unsigned long)(addr), (size)) #define user_addr_max() (uaccess_kernel() ? ~0UL : TASK_SIZE) @@ -86,7 +86,7 @@ extern long __put_user_bad(void); ({ \ long __pu_err = -EFAULT; \ __typeof__(*(ptr)) *__pu_addr = (ptr); \ - if (access_ok(VERIFY_WRITE, __pu_addr, size)) \ + if (access_ok(__pu_addr, size)) \ __put_user_size((x), __pu_addr, (size), __pu_err); \ __pu_err; \ }) @@ -183,7 +183,7 @@ __asm__ __volatile__( \ ({ \ long __gu_err = -EFAULT, __gu_val = 0; \ const __typeof__(*(ptr)) *__gu_addr = (ptr); \ - if (access_ok(VERIFY_READ, __gu_addr, size)) \ + if (access_ok(__gu_addr, size)) \ __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ __gu_err; \ @@ -269,7 +269,7 @@ __xtensa_clear_user(void *addr, unsigned long size) static inline unsigned long clear_user(void *addr, unsigned long size) { - if (access_ok(VERIFY_WRITE, addr, size)) + if (access_ok(addr, size)) return __xtensa_clear_user(addr, size); return size ? -EFAULT : 0; } @@ -284,7 +284,7 @@ extern long __strncpy_user(char *, const char *, long); static inline long strncpy_from_user(char *dst, const char *src, long count) { - if (access_ok(VERIFY_READ, src, 1)) + if (access_ok(src, 1)) return __strncpy_user(dst, src, count); return -EFAULT; } diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c index 74e1682876ac..dc22a238ed9c 100644 --- a/arch/xtensa/kernel/signal.c +++ b/arch/xtensa/kernel/signal.c @@ -251,7 +251,7 @@ asmlinkage long xtensa_rt_sigreturn(long a0, long a1, long a2, long a3, frame = (struct rt_sigframe __user *) regs->areg[1]; - if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + if (!access_ok(frame, sizeof(*frame))) goto badframe; if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) @@ -348,7 +348,7 @@ static int setup_frame(struct ksignal *ksig, sigset_t *set, if (regs->depc > 64) panic ("Double exception sys_sigreturn\n"); - if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) { + if (!access_ok(frame, sizeof(*frame))) { return -EFAULT; } diff --git a/arch/xtensa/kernel/stacktrace.c b/arch/xtensa/kernel/stacktrace.c index 0df4080fa20f..174c11f13bba 100644 --- a/arch/xtensa/kernel/stacktrace.c +++ b/arch/xtensa/kernel/stacktrace.c @@ -91,7 +91,7 @@ void xtensa_backtrace_user(struct pt_regs *regs, unsigned int depth, pc = MAKE_PC_FROM_RA(a0, pc); /* Check if the region is OK to access. */ - if (!access_ok(VERIFY_READ, &SPILL_SLOT(a1, 0), 8)) + if (!access_ok(&SPILL_SLOT(a1, 0), 8)) return; /* Copy a1, a0 from user space stack frame. */ if (__get_user(a0, &SPILL_SLOT(a1, 0)) || -- cgit v1.2.3-59-g8ed1b