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uaccess: fix type mismatch warnings from access_ok()
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On some architectures, access_ok() does not do any argument type
checking, so replacing the definition with a generic one causes
a few warnings for harmless issues that were never caught before.

Fix the ones that I found either through my own test builds or
that were reported by the 0-day bot.

Reported-by: kernel test robot <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Acked-by: Dinh Nguyen <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
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arndb committed Feb 25, 2022
1 parent 52fe8d1 commit 23fc539
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Showing 10 changed files with 23 additions and 21 deletions.
2 changes: 1 addition & 1 deletion arch/arc/kernel/process.c
Original file line number Diff line number Diff line change
Expand Up @@ -43,7 +43,7 @@ SYSCALL_DEFINE0(arc_gettls)
return task_thread_info(current)->thr_ptr;
}

SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
SYSCALL_DEFINE3(arc_usr_cmpxchg, int __user *, uaddr, int, expected, int, new)
{
struct pt_regs *regs = current_pt_regs();
u32 uval;
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2 changes: 1 addition & 1 deletion arch/arm/kernel/swp_emulate.c
Original file line number Diff line number Diff line change
Expand Up @@ -195,7 +195,7 @@ static int swp_handler(struct pt_regs *regs, unsigned int instr)
destreg, EXTRACT_REG_NUM(instr, RT2_OFFSET), data);

/* Check access in reasonable access range for both SWP and SWPB */
if (!access_ok((address & ~3), 4)) {
if (!access_ok((void __user *)(address & ~3), 4)) {
pr_debug("SWP{B} emulation: access to %p not allowed!\n",
(void *)address);
res = -EFAULT;
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2 changes: 1 addition & 1 deletion arch/arm/kernel/traps.c
Original file line number Diff line number Diff line change
Expand Up @@ -576,7 +576,7 @@ do_cache_op(unsigned long start, unsigned long end, int flags)
if (end < start || flags)
return -EINVAL;

if (!access_ok(start, end - start))
if (!access_ok((void __user *)start, end - start))
return -EFAULT;

return __do_cache_op(start, end);
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2 changes: 1 addition & 1 deletion arch/csky/kernel/perf_callchain.c
Original file line number Diff line number Diff line change
Expand Up @@ -49,7 +49,7 @@ static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry,
{
struct stackframe buftail;
unsigned long lr = 0;
unsigned long *user_frame_tail = (unsigned long *)fp;
unsigned long __user *user_frame_tail = (unsigned long __user *)fp;

/* Check accessibility of one struct frame_tail beyond */
if (!access_ok(user_frame_tail, sizeof(buftail)))
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2 changes: 1 addition & 1 deletion arch/csky/kernel/signal.c
Original file line number Diff line number Diff line change
Expand Up @@ -136,7 +136,7 @@ static inline void __user *get_sigframe(struct ksignal *ksig,
static int
setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
{
struct rt_sigframe *frame;
struct rt_sigframe __user *frame;
int err = 0;

frame = get_sigframe(ksig, regs, sizeof(*frame));
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20 changes: 11 additions & 9 deletions arch/nios2/kernel/signal.c
Original file line number Diff line number Diff line change
Expand Up @@ -36,10 +36,10 @@ struct rt_sigframe {

static inline int rt_restore_ucontext(struct pt_regs *regs,
struct switch_stack *sw,
struct ucontext *uc, int *pr2)
struct ucontext __user *uc, int *pr2)
{
int temp;
unsigned long *gregs = uc->uc_mcontext.gregs;
unsigned long __user *gregs = uc->uc_mcontext.gregs;
int err;

/* Always make any pending restarted system calls return -EINTR */
Expand Down Expand Up @@ -102,10 +102,11 @@ asmlinkage int do_rt_sigreturn(struct switch_stack *sw)
{
struct pt_regs *regs = (struct pt_regs *)(sw + 1);
/* Verify, can we follow the stack back */
struct rt_sigframe *frame = (struct rt_sigframe *) regs->sp;
struct rt_sigframe __user *frame;
sigset_t set;
int rval;

frame = (struct rt_sigframe __user *) regs->sp;
if (!access_ok(frame, sizeof(*frame)))
goto badframe;

Expand All @@ -124,10 +125,10 @@ asmlinkage int do_rt_sigreturn(struct switch_stack *sw)
return 0;
}

static inline int rt_setup_ucontext(struct ucontext *uc, struct pt_regs *regs)
static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
{
struct switch_stack *sw = (struct switch_stack *)regs - 1;
unsigned long *gregs = uc->uc_mcontext.gregs;
unsigned long __user *gregs = uc->uc_mcontext.gregs;
int err = 0;

err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
Expand Down Expand Up @@ -162,8 +163,9 @@ static inline int rt_setup_ucontext(struct ucontext *uc, struct pt_regs *regs)
return err;
}

static inline void *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
size_t frame_size)
static inline void __user *get_sigframe(struct ksignal *ksig,
struct pt_regs *regs,
size_t frame_size)
{
unsigned long usp;

Expand All @@ -174,13 +176,13 @@ static inline void *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
usp = sigsp(usp, ksig);

/* Verify, is it 32 or 64 bit aligned */
return (void *)((usp - frame_size) & -8UL);
return (void __user *)((usp - frame_size) & -8UL);
}

static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
struct pt_regs *regs)
{
struct rt_sigframe *frame;
struct rt_sigframe __user *frame;
int err = 0;

frame = get_sigframe(ksig, regs, sizeof(*frame));
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4 changes: 2 additions & 2 deletions arch/powerpc/lib/sstep.c
Original file line number Diff line number Diff line change
Expand Up @@ -112,9 +112,9 @@ static nokprobe_inline long address_ok(struct pt_regs *regs,
{
if (!user_mode(regs))
return 1;
if (__access_ok(ea, nb))
if (access_ok((void __user *)ea, nb))
return 1;
if (__access_ok(ea, 1))
if (access_ok((void __user *)ea, 1))
/* Access overlaps the end of the user region */
regs->dar = TASK_SIZE_MAX - 1;
else
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4 changes: 2 additions & 2 deletions arch/riscv/kernel/perf_callchain.c
Original file line number Diff line number Diff line change
Expand Up @@ -15,8 +15,8 @@ static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry,
{
struct stackframe buftail;
unsigned long ra = 0;
unsigned long *user_frame_tail =
(unsigned long *)(fp - sizeof(struct stackframe));
unsigned long __user *user_frame_tail =
(unsigned long __user *)(fp - sizeof(struct stackframe));

/* Check accessibility of one struct frame_tail beyond */
if (!access_ok(user_frame_tail, sizeof(buftail)))
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2 changes: 1 addition & 1 deletion arch/sparc/kernel/signal_32.c
Original file line number Diff line number Diff line change
Expand Up @@ -65,7 +65,7 @@ struct rt_signal_frame {
*/
static inline bool invalid_frame_pointer(void __user *fp, int fplen)
{
if ((((unsigned long) fp) & 15) || !__access_ok((unsigned long)fp, fplen))
if ((((unsigned long) fp) & 15) || !access_ok(fp, fplen))
return true;

return false;
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4 changes: 2 additions & 2 deletions lib/test_lockup.c
Original file line number Diff line number Diff line change
Expand Up @@ -417,8 +417,8 @@ static bool test_kernel_ptr(unsigned long addr, int size)
return false;

/* should be at least readable kernel address */
if (access_ok(ptr, 1) ||
access_ok(ptr + size - 1, 1) ||
if (access_ok((void __user *)ptr, 1) ||
access_ok((void __user *)ptr + size - 1, 1) ||
get_kernel_nofault(buf, ptr) ||
get_kernel_nofault(buf, ptr + size - 1)) {
pr_err("invalid kernel ptr: %#lx\n", addr);
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