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Merge tag 'uaccess_for_upstream' of git://git.kernel.org/pub/scm/linu…
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…x/kernel/git/mst/vhost into asm-generic

Merge "uaccess: fix sparse warning on get/put_user for bitwise types" from Michael S. Tsirkin:

At the moment, if p and x are both tagged as bitwise types,
some of get_user(x, p), put_user(x, p), __get_user(x, p), __put_user(x, p)
might produce a sparse warning on many architectures.
This is a false positive: *p on these architectures is loaded into long
(typically using asm), then cast back to typeof(*p).

When typeof(*p) is a bitwise type (which is uncommon), such a cast needs
__force, otherwise sparse produces a warning.

Some architectures already have the __force tag, add it
where it's missing.

I verified that adding these __force casts does not supress any useful warnings.

Specifically, vhost wants to read/write bitwise types in userspace memory
using get_user/put_user.
At the moment this triggers sparse errors, since the value is passed through an
integer.

For example:
    __le32 __user *p;
    __u32 x;

both
    put_user(x, p);
and
    get_user(x, p);
should be safe, but produce warnings on some architectures.

While there, I noticed that a bunch of architectures violated
coding style rules within uaccess macros.
Included patches to fix them up.

Signed-off-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

* tag 'uaccess_for_upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (37 commits)
  sparc32: nocheck uaccess coding style tweaks
  sparc64: nocheck uaccess coding style tweaks
  xtensa: macro whitespace fixes
  sh: macro whitespace fixes
  parisc: macro whitespace fixes
  m68k: macro whitespace fixes
  m32r: macro whitespace fixes
  frv: macro whitespace fixes
  cris: macro whitespace fixes
  avr32: macro whitespace fixes
  arm64: macro whitespace fixes
  arm: macro whitespace fixes
  alpha: macro whitespace fixes
  blackfin: macro whitespace fixes
  sparc64: uaccess_64 macro whitespace fixes
  sparc32: uaccess_32 macro whitespace fixes
  avr32: whitespace fix
  sh: fix put_user sparse errors
  metag: fix put_user sparse errors
  ia64: fix put_user sparse errors
  ...
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@arndb
arndb committed Jan 14, 2015
2 parents eaa27f3 + 0795cb1 commit 643165c
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Showing 21 changed files with 700 additions and 614 deletions.
86 changes: 43 additions & 43 deletions arch/alpha/include/asm/uaccess.h
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Original file line number Diff line number Diff line change
Expand Up @@ -27,7 +27,7 @@
#define get_ds() (KERNEL_DS)
#define set_fs(x) (current_thread_info()->addr_limit = (x))

#define segment_eq(a,b) ((a).seg == (b).seg)
#define segment_eq(a, b) ((a).seg == (b).seg)

/*
* Is a address valid? This does a straightforward calculation rather
Expand All @@ -39,13 +39,13 @@
* - AND "addr+size" doesn't have any high-bits set
* - OR we are in kernel mode.
*/
#define __access_ok(addr,size,segment) \
#define __access_ok(addr, size, segment) \
(((segment).seg & (addr | size | (addr+size))) == 0)

#define access_ok(type,addr,size) \
#define access_ok(type, addr, size) \
({ \
__chk_user_ptr(addr); \
__access_ok(((unsigned long)(addr)),(size),get_fs()); \
__access_ok(((unsigned long)(addr)), (size), get_fs()); \
})

/*
Expand All @@ -60,20 +60,20 @@
* (a) re-use the arguments for side effects (sizeof/typeof is ok)
* (b) require any knowledge of processes at this stage
*/
#define put_user(x,ptr) \
__put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)),get_fs())
#define get_user(x,ptr) \
__get_user_check((x),(ptr),sizeof(*(ptr)),get_fs())
#define put_user(x, ptr) \
__put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), get_fs())
#define get_user(x, ptr) \
__get_user_check((x), (ptr), sizeof(*(ptr)), get_fs())

/*
* The "__xxx" versions do not do address space checking, useful when
* doing multiple accesses to the same area (the programmer has to do the
* checks by hand with "access_ok()")
*/
#define __put_user(x,ptr) \
__put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
#define __get_user(x,ptr) \
__get_user_nocheck((x),(ptr),sizeof(*(ptr)))
#define __put_user(x, ptr) \
__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
#define __get_user(x, ptr) \
__get_user_nocheck((x), (ptr), sizeof(*(ptr)))

/*
* The "lda %1, 2b-1b(%0)" bits are magic to get the assembler to
Expand All @@ -84,7 +84,7 @@

extern void __get_user_unknown(void);

#define __get_user_nocheck(x,ptr,size) \
#define __get_user_nocheck(x, ptr, size) \
({ \
long __gu_err = 0; \
unsigned long __gu_val; \
Expand All @@ -96,16 +96,16 @@ extern void __get_user_unknown(void);
case 8: __get_user_64(ptr); break; \
default: __get_user_unknown(); break; \
} \
(x) = (__typeof__(*(ptr))) __gu_val; \
(x) = (__force __typeof__(*(ptr))) __gu_val; \
__gu_err; \
})

#define __get_user_check(x,ptr,size,segment) \
#define __get_user_check(x, ptr, size, segment) \
({ \
long __gu_err = -EFAULT; \
unsigned long __gu_val = 0; \
const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
if (__access_ok((unsigned long)__gu_addr,size,segment)) { \
if (__access_ok((unsigned long)__gu_addr, size, segment)) { \
__gu_err = 0; \
switch (size) { \
case 1: __get_user_8(__gu_addr); break; \
Expand All @@ -115,7 +115,7 @@ extern void __get_user_unknown(void);
default: __get_user_unknown(); break; \
} \
} \
(x) = (__typeof__(*(ptr))) __gu_val; \
(x) = (__force __typeof__(*(ptr))) __gu_val; \
__gu_err; \
})

Expand Down Expand Up @@ -201,31 +201,31 @@ struct __large_struct { unsigned long buf[100]; };

extern void __put_user_unknown(void);

#define __put_user_nocheck(x,ptr,size) \
#define __put_user_nocheck(x, ptr, size) \
({ \
long __pu_err = 0; \
__chk_user_ptr(ptr); \
switch (size) { \
case 1: __put_user_8(x,ptr); break; \
case 2: __put_user_16(x,ptr); break; \
case 4: __put_user_32(x,ptr); break; \
case 8: __put_user_64(x,ptr); break; \
case 1: __put_user_8(x, ptr); break; \
case 2: __put_user_16(x, ptr); break; \
case 4: __put_user_32(x, ptr); break; \
case 8: __put_user_64(x, ptr); break; \
default: __put_user_unknown(); break; \
} \
__pu_err; \
})

#define __put_user_check(x,ptr,size,segment) \
#define __put_user_check(x, ptr, size, segment) \
({ \
long __pu_err = -EFAULT; \
__typeof__(*(ptr)) __user *__pu_addr = (ptr); \
if (__access_ok((unsigned long)__pu_addr,size,segment)) { \
if (__access_ok((unsigned long)__pu_addr, size, segment)) { \
__pu_err = 0; \
switch (size) { \
case 1: __put_user_8(x,__pu_addr); break; \
case 2: __put_user_16(x,__pu_addr); break; \
case 4: __put_user_32(x,__pu_addr); break; \
case 8: __put_user_64(x,__pu_addr); break; \
case 1: __put_user_8(x, __pu_addr); break; \
case 2: __put_user_16(x, __pu_addr); break; \
case 4: __put_user_32(x, __pu_addr); break; \
case 8: __put_user_64(x, __pu_addr); break; \
default: __put_user_unknown(); break; \
} \
} \
Expand All @@ -237,7 +237,7 @@ extern void __put_user_unknown(void);
* instead of writing: this is because they do not write to
* any memory gcc knows about, so there are no aliasing issues
*/
#define __put_user_64(x,addr) \
#define __put_user_64(x, addr) \
__asm__ __volatile__("1: stq %r2,%1\n" \
"2:\n" \
".section __ex_table,\"a\"\n" \
Expand All @@ -247,7 +247,7 @@ __asm__ __volatile__("1: stq %r2,%1\n" \
: "=r"(__pu_err) \
: "m" (__m(addr)), "rJ" (x), "0"(__pu_err))

#define __put_user_32(x,addr) \
#define __put_user_32(x, addr) \
__asm__ __volatile__("1: stl %r2,%1\n" \
"2:\n" \
".section __ex_table,\"a\"\n" \
Expand All @@ -260,7 +260,7 @@ __asm__ __volatile__("1: stl %r2,%1\n" \
#ifdef __alpha_bwx__
/* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */

#define __put_user_16(x,addr) \
#define __put_user_16(x, addr) \
__asm__ __volatile__("1: stw %r2,%1\n" \
"2:\n" \
".section __ex_table,\"a\"\n" \
Expand All @@ -270,7 +270,7 @@ __asm__ __volatile__("1: stw %r2,%1\n" \
: "=r"(__pu_err) \
: "m"(__m(addr)), "rJ"(x), "0"(__pu_err))

#define __put_user_8(x,addr) \
#define __put_user_8(x, addr) \
__asm__ __volatile__("1: stb %r2,%1\n" \
"2:\n" \
".section __ex_table,\"a\"\n" \
Expand All @@ -283,7 +283,7 @@ __asm__ __volatile__("1: stb %r2,%1\n" \
/* Unfortunately, we can't get an unaligned access trap for the sub-word
write, so we have to do a general unaligned operation. */

#define __put_user_16(x,addr) \
#define __put_user_16(x, addr) \
{ \
long __pu_tmp1, __pu_tmp2, __pu_tmp3, __pu_tmp4; \
__asm__ __volatile__( \
Expand All @@ -308,13 +308,13 @@ __asm__ __volatile__("1: stb %r2,%1\n" \
" .long 4b - .\n" \
" lda $31, 5b-4b(%0)\n" \
".previous" \
: "=r"(__pu_err), "=&r"(__pu_tmp1), \
"=&r"(__pu_tmp2), "=&r"(__pu_tmp3), \
: "=r"(__pu_err), "=&r"(__pu_tmp1), \
"=&r"(__pu_tmp2), "=&r"(__pu_tmp3), \
"=&r"(__pu_tmp4) \
: "r"(addr), "r"((unsigned long)(x)), "0"(__pu_err)); \
}

#define __put_user_8(x,addr) \
#define __put_user_8(x, addr) \
{ \
long __pu_tmp1, __pu_tmp2; \
__asm__ __volatile__( \
Expand All @@ -330,7 +330,7 @@ __asm__ __volatile__("1: stb %r2,%1\n" \
" .long 2b - .\n" \
" lda $31, 3b-2b(%0)\n" \
".previous" \
: "=r"(__pu_err), \
: "=r"(__pu_err), \
"=&r"(__pu_tmp1), "=&r"(__pu_tmp2) \
: "r"((unsigned long)(x)), "r"(addr), "0"(__pu_err)); \
}
Expand Down Expand Up @@ -366,7 +366,7 @@ __copy_tofrom_user_nocheck(void *to, const void *from, long len)
: "=r" (__cu_len), "=r" (__cu_from), "=r" (__cu_to)
: __module_address(__copy_user)
"0" (__cu_len), "1" (__cu_from), "2" (__cu_to)
: "$1","$2","$3","$4","$5","$28","memory");
: "$1", "$2", "$3", "$4", "$5", "$28", "memory");

return __cu_len;
}
Expand All @@ -379,15 +379,15 @@ __copy_tofrom_user(void *to, const void *from, long len, const void __user *vali
return len;
}

#define __copy_to_user(to,from,n) \
#define __copy_to_user(to, from, n) \
({ \
__chk_user_ptr(to); \
__copy_tofrom_user_nocheck((__force void *)(to),(from),(n)); \
__copy_tofrom_user_nocheck((__force void *)(to), (from), (n)); \
})
#define __copy_from_user(to,from,n) \
#define __copy_from_user(to, from, n) \
({ \
__chk_user_ptr(from); \
__copy_tofrom_user_nocheck((to),(__force void *)(from),(n)); \
__copy_tofrom_user_nocheck((to), (__force void *)(from), (n)); \
})

#define __copy_to_user_inatomic __copy_to_user
Expand Down Expand Up @@ -418,7 +418,7 @@ __clear_user(void __user *to, long len)
: "=r"(__cl_len), "=r"(__cl_to)
: __module_address(__do_clear_user)
"0"(__cl_len), "1"(__cl_to)
: "$1","$2","$3","$4","$5","$28","memory");
: "$1", "$2", "$3", "$4", "$5", "$28", "memory");
return __cl_len;
}

Expand Down
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