[PATCH 21/23] maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault

Christoph Hellwig
2020-05-21T15:24:42Z

Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/powerpc/kernel/process.c | 3 ++-
arch/powerpc/kvm/book3s_64_mmu_radix.c | 4 ++--
arch/powerpc/mm/fault.c | 2 +-
arch/powerpc/oprofile/backtrace.c | 6 ++++--
arch/powerpc/perf/callchain_32.c | 2 +-
arch/powerpc/perf/callchain_64.c | 2 +-
arch/powerpc/perf/core-book3s.c | 3 ++-
arch/powerpc/sysdev/fsl_pci.c | 4 ++--
include/linux/uaccess.h | 4 ++--
kernel/trace/bpf_trace.c | 4 ++--
kernel/trace/trace_kprobe.c | 2 +-
mm/maccess.c | 10 +++++-----
12 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 9c21288f86455..d5d6136b13480 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1294,7 +1294,8 @@ void show_user_instructions(struct pt_regs *regs)
for (i = 0; i < 8 && n; i++, n--, pc += sizeof(int)) {
int instr;

- if (probe_user_read(&instr, (void __user *)pc, sizeof(instr))) {
+ if (copy_from_user_nofault(&instr, (void __user *)pc,
+ sizeof(instr))) {
seq_buf_printf(&s, "XXXXXXXX ");
continue;
}
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index aa12cd4078b32..9d25f2eb5a33a 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -64,9 +64,9 @@ unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid,
isync();

if (is_load)
- ret = probe_user_read(to, (const void __user *)from, n);
+ ret = copy_from_user_nofault(to, (const void __user *)from, n);
else
- ret = probe_user_write((void __user *)to, from, n);
+ ret = copy_to_user_nofault((void __user *)to, from, n);

/* switch the pid first to avoid running host with unallocated pid */
if (quadrant == 1 && pid != old_pid)
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 84af6c8eecf71..231664fe9d126 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -280,7 +280,7 @@ static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address,
access_ok(nip, sizeof(*nip))) {
unsigned int inst;

- if (!probe_user_read(&inst, nip, sizeof(inst)))
+ if (!copy_from_user_nofault(&inst, nip, sizeof(inst)))
return !store_updates_sp(inst);
*must_retry = true;
}
diff --git a/arch/powerpc/oprofile/backtrace.c b/arch/powerpc/oprofile/backtrace.c
index 6f347fa29f41e..9db7ada79d10d 100644
--- a/arch/powerpc/oprofile/backtrace.c
+++ b/arch/powerpc/oprofile/backtrace.c
@@ -33,7 +33,8 @@ static unsigned int user_getsp32(unsigned int sp, int is_first)
* which means that we've done all that we can do from
* interrupt context.
*/
- if (probe_user_read(stack_frame, (void __user *)p, sizeof(stack_frame)))
+ if (copy_from_user_nofault(stack_frame, (void __user *)p,
+ sizeof(stack_frame)))
return 0;

if (!is_first)
@@ -51,7 +52,8 @@ static unsigned long user_getsp64(unsigned long sp, int is_first)
{
unsigned long stack_frame[3];

- if (probe_user_read(stack_frame, (void __user *)sp, sizeof(stack_frame)))
+ if (copy_from_user_nofault(stack_frame, (void __user *)sp,
+ sizeof(stack_frame)))
return 0;

if (!is_first)
diff --git a/arch/powerpc/perf/callchain_32.c b/arch/powerpc/perf/callchain_32.c
index 8aa9510031415..2e21849f82b18 100644
--- a/arch/powerpc/perf/callchain_32.c
+++ b/arch/powerpc/perf/callchain_32.c
@@ -45,7 +45,7 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
((unsigned long)ptr & 3))
return -EFAULT;

- rc = probe_user_read(ret, ptr, sizeof(*ret));
+ rc = copy_from_user_nofault(ret, ptr, sizeof(*ret));

if (IS_ENABLED(CONFIG_PPC64) && rc)
return read_user_stack_slow(ptr, ret, 4);
diff --git a/arch/powerpc/perf/callchain_64.c b/arch/powerpc/perf/callchain_64.c
index df1ffd8b20f21..7b0121694ebb7 100644
--- a/arch/powerpc/perf/callchain_64.c
+++ b/arch/powerpc/perf/callchain_64.c
@@ -71,7 +71,7 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
((unsigned long)ptr & 7))
return -EFAULT;

- if (!probe_user_read(ret, ptr, sizeof(*ret)))
+ if (!copy_from_user_nofault(ret, ptr, sizeof(*ret)))
return 0;

return read_user_stack_slow(ptr, ret, 8);
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index 50bc9f0eb6be3..f8072d1e5d172 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -426,7 +426,8 @@ static __u64 power_pmu_bhrb_to(u64 addr)
}

/* Userspace: need copy instruction here then translate it */
- if (probe_user_read(&instr, (unsigned int __user *)addr, sizeof(instr)))
+ if (copy_from_user_nofault(&instr, (unsigned int __user *)addr,
+ sizeof(instr)))
return 0;

target = branch_target(&instr);
diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index 4a8874bc10574..73fa37ca40ef9 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -1066,8 +1066,8 @@ int fsl_pci_mcheck_exception(struct pt_regs *regs)

if (is_in_pci_mem_space(addr)) {
if (user_mode(regs))
- ret = probe_user_read(&inst, (void __user *)regs->nip,
- sizeof(inst));
+ ret = copy_from_user_nofault(&inst,
+ (void __user *)regs->nip, sizeof(inst));
else
ret = probe_kernel_address((void *)regs->nip, inst);

diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 329e8479798de..5214d2f1f2cef 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -306,8 +306,8 @@ bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size);
long copy_from_kernel_nofault(void *dst, const void *src, size_t size);
long notrace copy_to_kernel_nofault(void *dst, const void *src, size_t size);

-extern long probe_user_read(void *dst, const void __user *src, size_t size);
-extern long notrace probe_user_write(void __user *dst, const void *src,
+long copy_from_user_nofault(void *dst, const void __user *src, size_t size);
+long notrace copy_to_user_nofault(void __user *dst, const void *src,
size_t size);

long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr,
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 59fec6e226db7..580ceefe23059 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -141,7 +141,7 @@ bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
{
int ret;

- ret = probe_user_read(dst, unsafe_ptr, size);
+ ret = copy_from_user_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
memset(dst, 0, size);
return ret;
@@ -326,7 +326,7 @@ BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
if (unlikely(!nmi_uaccess_okay()))
return -EPERM;

- return probe_user_write(unsafe_ptr, src, size);
+ return copy_to_user_nofault(unsafe_ptr, src, size);
}

static const struct bpf_func_proto bpf_probe_write_user_proto = {
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 430e64c4117ee..af4dd69bcc398 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1290,7 +1290,7 @@ probe_mem_read_user(void *dest, void *src, size_t size)
{
const void __user *uaddr = (__force const void __user *)src;

- return probe_user_read(dest, uaddr, size);
+ return copy_from_user_nofault(dest, uaddr, size);
}

static nokprobe_inline int
diff --git a/mm/maccess.c b/mm/maccess.c
index 43ed419f38401..349b6cb14426c 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c
@@ -192,7 +192,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
#endif /* HAVE_GET_KERNEL_NOFAULT */

/**
- * probe_user_read(): safely attempt to read from a user-space location
+ * copy_from_user_nofault(): safely attempt to read from a user-space location
* @dst: pointer to the buffer that shall take the data
* @src: address to read from. This must be a user address.
* @size: size of the data chunk
@@ -200,7 +200,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
* Safely read from user address @src to the buffer at @dst. If a kernel fault
* happens, handle that and return -EFAULT.
*/
-long probe_user_read(void *dst, const void __user *src, size_t size)
+long copy_from_user_nofault(void *dst, const void __user *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
@@ -217,10 +217,10 @@ long probe_user_read(void *dst, const void __user *src, size_t size)
return -EFAULT;
return 0;
}
-EXPORT_SYMBOL_GPL(probe_user_read);
+EXPORT_SYMBOL_GPL(copy_from_user_nofault);

/**
- * probe_user_write(): safely attempt to write to a user-space location
+ * copy_to_user_nofault(): safely attempt to write to a user-space location
* @dst: address to write to
* @src: pointer to the data that shall be written
* @size: size of the data chunk
@@ -228,7 +228,7 @@ EXPORT_SYMBOL_GPL(probe_user_read);
* Safely write to address @dst from the buffer at @src. If a kernel fault
* happens, handle that and return -EFAULT.
*/
-long probe_user_write(void __user *dst, const void *src, size_t size)
+long copy_to_user_nofault(void __user *dst, const void *src, size_t size)
{
long ret = -EFAULT;
mm_segment_t old_fs = get_fs();
--
2.26.2