From 73e800ecb67bf24c0508c63350c1dc509f00b1ce Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 16 Feb 2020 14:56:36 -0500 Subject: x86_64: csum_..._copy_..._user(): switch to unsafe_..._user() We already have stac/clac pair around the calls of csum_partial_copy_generic(). Stretch that area back, so that it covers the preceding loop (and convert the loop body from __{get,put}_user() to unsafe_{get,put}_user()). That brings the beginning of the areas to the earlier access_ok(), which allows to convert them into user_access_{begin,end}() ones. Signed-off-by: Al Viro --- arch/x86/lib/csum-wrappers_64.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) (limited to 'arch') diff --git a/arch/x86/lib/csum-wrappers_64.c b/arch/x86/lib/csum-wrappers_64.c index 875c2f5968a0..7028d1dc5c6b 100644 --- a/arch/x86/lib/csum-wrappers_64.c +++ b/arch/x86/lib/csum-wrappers_64.c @@ -27,7 +27,7 @@ csum_partial_copy_from_user(const void __user *src, void *dst, might_sleep(); *errp = 0; - if (!likely(access_ok(src, len))) + if (!user_access_begin(src, len)) goto out_err; /* @@ -42,8 +42,7 @@ csum_partial_copy_from_user(const void __user *src, void *dst, while (((unsigned long)src & 6) && len >= 2) { __u16 val16; - if (__get_user(val16, (const __u16 __user *)src)) - goto out_err; + unsafe_get_user(val16, (const __u16 __user *)src, out); *(__u16 *)dst = val16; isum = (__force __wsum)add32_with_carry( @@ -53,15 +52,16 @@ csum_partial_copy_from_user(const void __user *src, void *dst, len -= 2; } } - stac(); isum = csum_partial_copy_generic((__force const void *)src, dst, len, isum, errp, NULL); - clac(); + user_access_end(); if (unlikely(*errp)) goto out_err; return isum; +out: + user_access_end(); out_err: *errp = -EFAULT; memset(dst, 0, len); @@ -89,7 +89,7 @@ csum_and_copy_to_user(const void *src, void __user *dst, might_sleep(); - if (unlikely(!access_ok(dst, len))) { + if (!user_access_begin(dst, len)) { *errp = -EFAULT; return 0; } @@ -100,9 +100,7 @@ csum_and_copy_to_user(const void *src, void __user *dst, isum = (__force __wsum)add32_with_carry( (__force unsigned)isum, val16); - *errp = __put_user(val16, (__u16 __user *)dst); - if (*errp) - return isum; + unsafe_put_user(val16, (__u16 __user *)dst, out); src += 2; dst += 2; len -= 2; @@ -110,11 +108,14 @@ csum_and_copy_to_user(const void *src, void __user *dst, } *errp = 0; - stac(); ret = csum_partial_copy_generic(src, (void __force *)dst, len, isum, NULL, errp); - clac(); + user_access_end(); return ret; +out: + user_access_end(); + *errp = -EFAULT; + return isum; } EXPORT_SYMBOL(csum_and_copy_to_user); -- cgit v1.2.3-59-g8ed1b