[PATCH 5.16 0838/1017] uaccess: fix type mismatch warnings from access_ok()

Greg Kroah-Hartman
2022-04-05T10:27:42Z

From: Arnd Bergmann <arnd@arndb.de>

[ Upstream commit 23fc539e81295b14b50c6ccc5baeb4f3d59d822d ]

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 <lkp@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arc/kernel/process.c | 2 +-
arch/arm/kernel/swp_emulate.c | 2 +-
arch/arm/kernel/traps.c | 2 +-
arch/csky/kernel/perf_callchain.c | 2 +-
arch/csky/kernel/signal.c | 2 +-
arch/nios2/kernel/signal.c | 20 +++++++++++---------
arch/powerpc/lib/sstep.c | 4 ++--
arch/riscv/kernel/perf_callchain.c | 4 ++--
arch/sparc/kernel/signal_32.c | 2 +-
lib/test_lockup.c | 4 ++--
10 files changed, 23 insertions(+), 21 deletions(-)

diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index 8e90052f6f05..5f7f5aab361f 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -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;
diff --git a/arch/arm/kernel/swp_emulate.c b/arch/arm/kernel/swp_emulate.c
index 6166ba38bf99..b74bfcf94fb1 100644
--- a/arch/arm/kernel/swp_emulate.c
+++ b/arch/arm/kernel/swp_emulate.c
@@ -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;
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 90c887aa67a4..f74460d3bef5 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -575,7 +575,7 @@ 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);
diff --git a/arch/csky/kernel/perf_callchain.c b/arch/csky/kernel/perf_callchain.c
index 35318a635a5f..75e1f9df5f60 100644
--- a/arch/csky/kernel/perf_callchain.c
+++ b/arch/csky/kernel/perf_callchain.c
@@ -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)))
diff --git a/arch/csky/kernel/signal.c b/arch/csky/kernel/signal.c
index c7b763d2f526..8867ddf3e6c7 100644
--- a/arch/csky/kernel/signal.c
+++ b/arch/csky/kernel/signal.c
@@ -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));
diff --git a/arch/nios2/kernel/signal.c b/arch/nios2/kernel/signal.c
index 2009ae2d3c3b..386e46443b60 100644
--- a/arch/nios2/kernel/signal.c
+++ b/arch/nios2/kernel/signal.c
@@ -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 */
@@ -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;

@@ -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);
@@ -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;

@@ -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));
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index b042fcae3913..66d6f7003b18 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -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
diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c
index d82c291c1e4c..357f985041cb 100644
--- a/arch/riscv/kernel/perf_callchain.c
+++ b/arch/riscv/kernel/perf_callchain.c
@@ -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)))
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index ffab16369bea..74f80443b195 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -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;
diff --git a/lib/test_lockup.c b/lib/test_lockup.c
index 906b598740a7..6a0f329a794a 100644
--- a/lib/test_lockup.c
+++ b/lib/test_lockup.c
@@ -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);
--
2.34.1