2019-04-01 13:45:26

by Steven Rostedt

[permalink] [raw]
Subject: [PATCH 6/6 v3] syscalls: Remove start and number from syscall_set_arguments() args

From: "Steven Rostedt (VMware)" <[email protected]>

After removing the start and count arguments of syscall_get_arguments() it
seems reasonable to remove them from syscall_set_arguments(). Note, as of
today, there are no users of syscall_set_arguments(). But we are told that
there will be soon. But for now, at least make it consistent with
syscall_get_arguments().

Link: http://lkml.kernel.org/r/[email protected]

Cc: Oleg Nesterov <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Dominik Brodowski <[email protected]>
Cc: Dave Martin <[email protected]>
Cc: "Dmitry V. Levin" <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Steven Rostedt (VMware) <[email protected]>
---
arch/arm/include/asm/syscall.h | 22 ++-------
arch/arm64/include/asm/syscall.h | 22 ++-------
arch/c6x/include/asm/syscall.h | 38 +++------------
arch/csky/include/asm/syscall.h | 14 ++----
arch/ia64/include/asm/syscall.h | 10 ++--
arch/ia64/kernel/ptrace.c | 7 ++-
arch/microblaze/include/asm/syscall.h | 4 +-
arch/nds32/include/asm/syscall.h | 29 ++---------
arch/nios2/include/asm/syscall.h | 42 +++-------------
arch/openrisc/include/asm/syscall.h | 6 +--
arch/powerpc/include/asm/syscall.h | 7 +--
arch/riscv/include/asm/syscall.h | 13 ++---
arch/s390/include/asm/syscall.h | 11 ++---
arch/sh/include/asm/syscall_32.h | 21 +++-----
arch/sh/include/asm/syscall_64.h | 4 +-
arch/sparc/include/asm/syscall.h | 7 ++-
arch/um/include/asm/syscall-generic.h | 39 +++------------
arch/x86/include/asm/syscall.h | 69 +++++++--------------------
arch/xtensa/include/asm/syscall.h | 17 ++-----
include/asm-generic/syscall.h | 10 +---
20 files changed, 88 insertions(+), 304 deletions(-)

diff --git a/arch/arm/include/asm/syscall.h b/arch/arm/include/asm/syscall.h
index db969a2972ae..080ce70cab12 100644
--- a/arch/arm/include/asm/syscall.h
+++ b/arch/arm/include/asm/syscall.h
@@ -65,26 +65,12 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- if (n == 0)
- return;
-
- if (i + n > SYSCALL_MAX_ARGS) {
- pr_warn("%s called with max args %d, handling only %d\n",
- __func__, i + n, SYSCALL_MAX_ARGS);
- n = SYSCALL_MAX_ARGS - i;
- }
-
- if (i == 0) {
- regs->ARM_ORIG_r0 = args[0];
- args++;
- i++;
- n--;
- }
-
- memcpy(&regs->ARM_r0 + i, args, n * sizeof(args[0]));
+ regs->ARM_ORIG_r0 = args[0];
+ args++;
+
+ memcpy(&regs->ARM_r0 + 1, args, 5 * sizeof(args[0]));
}

static inline int syscall_get_arch(void)
diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h
index 55b2dab21023..a179df3674a1 100644
--- a/arch/arm64/include/asm/syscall.h
+++ b/arch/arm64/include/asm/syscall.h
@@ -75,26 +75,12 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- if (n == 0)
- return;
-
- if (i + n > SYSCALL_MAX_ARGS) {
- pr_warning("%s called with max args %d, handling only %d\n",
- __func__, i + n, SYSCALL_MAX_ARGS);
- n = SYSCALL_MAX_ARGS - i;
- }
-
- if (i == 0) {
- regs->orig_x0 = args[0];
- args++;
- i++;
- n--;
- }
-
- memcpy(&regs->regs[i], args, n * sizeof(args[0]));
+ regs->orig_x0 = args[0];
+ args++;
+
+ memcpy(&regs->regs[1], args, 5 * sizeof(args[0]));
}

/*
diff --git a/arch/c6x/include/asm/syscall.h b/arch/c6x/include/asm/syscall.h
index 06db3251926b..15ba8599858e 100644
--- a/arch/c6x/include/asm/syscall.h
+++ b/arch/c6x/include/asm/syscall.h
@@ -59,40 +59,14 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- switch (i) {
- case 0:
- if (!n--)
- break;
- regs->a4 = *args++;
- case 1:
- if (!n--)
- break;
- regs->b4 = *args++;
- case 2:
- if (!n--)
- break;
- regs->a6 = *args++;
- case 3:
- if (!n--)
- break;
- regs->b6 = *args++;
- case 4:
- if (!n--)
- break;
- regs->a8 = *args++;
- case 5:
- if (!n--)
- break;
- regs->a9 = *args++;
- case 6:
- if (!n)
- break;
- default:
- BUG();
- }
+ regs->a4 = *args++;
+ regs->b4 = *args++;
+ regs->a6 = *args++;
+ regs->b6 = *args++;
+ regs->a8 = *args++;
+ regs->a9 = *args;
}

#endif /* __ASM_C6X_SYSCALLS_H */
diff --git a/arch/csky/include/asm/syscall.h b/arch/csky/include/asm/syscall.h
index c691fe92edc6..bda0a446c63e 100644
--- a/arch/csky/include/asm/syscall.h
+++ b/arch/csky/include/asm/syscall.h
@@ -52,17 +52,11 @@ syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,

static inline void
syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
- unsigned int i, unsigned int n, const unsigned long *args)
+ const unsigned long *args)
{
- BUG_ON(i + n > 6);
- if (i == 0) {
- regs->orig_a0 = args[0];
- args++;
- n--;
- } else {
- i--;
- }
- memcpy(&regs->a1 + i, args, n * sizeof(regs->a1));
+ regs->orig_a0 = args[0];
+ args++;
+ memcpy(&regs->a1, args, 5 * sizeof(regs->a1));
}

static inline int
diff --git a/arch/ia64/include/asm/syscall.h b/arch/ia64/include/asm/syscall.h
index 8204c1ff70ce..0d9e7fab4a79 100644
--- a/arch/ia64/include/asm/syscall.h
+++ b/arch/ia64/include/asm/syscall.h
@@ -59,23 +59,19 @@ static inline void syscall_set_return_value(struct task_struct *task,
}

extern void ia64_syscall_get_set_arguments(struct task_struct *task,
- struct pt_regs *regs, unsigned int i, unsigned int n,
- unsigned long *args, int rw);
+ struct pt_regs *regs, unsigned long *args, int rw);
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned long *args)
{
- ia64_syscall_get_set_arguments(task, regs, 0, 6, args, 0);
+ ia64_syscall_get_set_arguments(task, regs, args, 0);
}

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
unsigned long *args)
{
- BUG_ON(i + n > 6);
-
- ia64_syscall_get_set_arguments(task, regs, i, n, args, 1);
+ ia64_syscall_get_set_arguments(task, regs, args, 1);
}

static inline int syscall_get_arch(void)
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c
index 6d50ede0ed69..bf9c24d9ce84 100644
--- a/arch/ia64/kernel/ptrace.c
+++ b/arch/ia64/kernel/ptrace.c
@@ -2179,12 +2179,11 @@ static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
}

void ia64_syscall_get_set_arguments(struct task_struct *task,
- struct pt_regs *regs, unsigned int i, unsigned int n,
- unsigned long *args, int rw)
+ struct pt_regs *regs, unsigned long *args, int rw)
{
struct syscall_get_set_args data = {
- .i = i,
- .n = n,
+ .i = 0,
+ .n = 6,
.args = args,
.regs = regs,
.rw = rw,
diff --git a/arch/microblaze/include/asm/syscall.h b/arch/microblaze/include/asm/syscall.h
index 4b23e44e5c3c..833d3a53dab3 100644
--- a/arch/microblaze/include/asm/syscall.h
+++ b/arch/microblaze/include/asm/syscall.h
@@ -93,9 +93,11 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
+ unsigned int i = 0;
+ unsigned int n = 6;
+
while (n--)
microblaze_set_syscall_arg(regs, i++, *args++);
}
diff --git a/arch/nds32/include/asm/syscall.h b/arch/nds32/include/asm/syscall.h
index 89a6ec8731d8..671ebd357496 100644
--- a/arch/nds32/include/asm/syscall.h
+++ b/arch/nds32/include/asm/syscall.h
@@ -129,39 +129,20 @@ void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
* syscall_set_arguments - change system call parameter value
* @task: task of interest, must be in system call entry tracing
* @regs: task_pt_regs() of @task
- * @i: argument index [0,5]
- * @n: number of arguments; n+i must be [1,6].
* @args: array of argument values to store
*
- * Changes @n arguments to the system call starting with the @i'th argument.
- * Argument @i gets value @args[0], and so on.
- * An arch inline version is probably optimal when @i and @n are constants.
+ * Changes 6 arguments to the system call. The first argument gets value
+ * @args[0], and so on.
*
* It's only valid to call this when @task is stopped for tracing on
* entry to a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
- * It's invalid to call this with @i + @n > 6; we only support system calls
- * taking up to 6 arguments.
*/
void syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- if (n == 0)
- return;
-
- if (i + n > SYSCALL_MAX_ARGS) {
- pr_warn("%s called with max args %d, handling only %d\n",
- __func__, i + n, SYSCALL_MAX_ARGS);
- n = SYSCALL_MAX_ARGS - i;
- }
-
- if (i == 0) {
- regs->orig_r0 = args[0];
- args++;
- i++;
- n--;
- }
+ regs->orig_r0 = args[0];
+ args++;

- memcpy(&regs->uregs[0] + i, args, n * sizeof(args[0]));
+ memcpy(&regs->uregs[0] + 1, args, 5 * sizeof(args[0]));
}
#endif /* _ASM_NDS32_SYSCALL_H */
diff --git a/arch/nios2/include/asm/syscall.h b/arch/nios2/include/asm/syscall.h
index 792bd449d839..d7624ed06efb 100644
--- a/arch/nios2/include/asm/syscall.h
+++ b/arch/nios2/include/asm/syscall.h
@@ -69,42 +69,14 @@ static inline void syscall_get_arguments(struct task_struct *task,
}

static inline void syscall_set_arguments(struct task_struct *task,
- struct pt_regs *regs, unsigned int i, unsigned int n,
- const unsigned long *args)
+ struct pt_regs *regs, const unsigned long *args)
{
- BUG_ON(i + n > 6);
-
- switch (i) {
- case 0:
- if (!n--)
- break;
- regs->r4 = *args++;
- case 1:
- if (!n--)
- break;
- regs->r5 = *args++;
- case 2:
- if (!n--)
- break;
- regs->r6 = *args++;
- case 3:
- if (!n--)
- break;
- regs->r7 = *args++;
- case 4:
- if (!n--)
- break;
- regs->r8 = *args++;
- case 5:
- if (!n--)
- break;
- regs->r9 = *args++;
- case 6:
- if (!n)
- break;
- default:
- BUG();
- }
+ regs->r4 = *args++;
+ regs->r5 = *args++;
+ regs->r6 = *args++;
+ regs->r7 = *args++;
+ regs->r8 = *args++;
+ regs->r9 = *args;
}

#endif
diff --git a/arch/openrisc/include/asm/syscall.h b/arch/openrisc/include/asm/syscall.h
index 72607860cd55..b4ff07c1baed 100644
--- a/arch/openrisc/include/asm/syscall.h
+++ b/arch/openrisc/include/asm/syscall.h
@@ -63,11 +63,9 @@ syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,

static inline void
syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
- unsigned int i, unsigned int n, const unsigned long *args)
+ const unsigned long *args)
{
- BUG_ON(i + n > 6);
-
- memcpy(&regs->gpr[3 + i], args, n * sizeof(args[0]));
+ memcpy(&regs->gpr[3], args, 6 * sizeof(args[0]));
}

static inline int syscall_get_arch(void)
diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h
index 5c9b9dc82b7e..1243045bad2d 100644
--- a/arch/powerpc/include/asm/syscall.h
+++ b/arch/powerpc/include/asm/syscall.h
@@ -86,15 +86,12 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- BUG_ON(i + n > 6);
- memcpy(&regs->gpr[3 + i], args, n * sizeof(args[0]));
+ memcpy(&regs->gpr[3], args, 6 * sizeof(args[0]));

/* Also copy the first argument into orig_gpr3 */
- if (i == 0 && n > 0)
- regs->orig_gpr3 = args[0];
+ regs->orig_gpr3 = args[0];
}

static inline int syscall_get_arch(void)
diff --git a/arch/riscv/include/asm/syscall.h b/arch/riscv/include/asm/syscall.h
index 6adca1804be1..a3d5273ded7c 100644
--- a/arch/riscv/include/asm/syscall.h
+++ b/arch/riscv/include/asm/syscall.h
@@ -81,18 +81,11 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- BUG_ON(i + n > 6);
- if (i == 0) {
- regs->orig_a0 = args[0];
- args++;
- n--;
- } else {
- i--;
- }
- memcpy(&regs->a1 + i, args, n * sizeof(regs->a1));
+ regs->orig_a0 = args[0];
+ args++;
+ memcpy(&regs->a1, args, 5 * sizeof(regs->a1));
}

static inline int syscall_get_arch(void)
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index ee0b1f6aa36d..59c3e91f2cdb 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -74,15 +74,14 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- BUG_ON(i + n > 6);
+ unsigned int n = 6;
+
while (n-- > 0)
- if (i + n > 0)
- regs->gprs[2 + i + n] = args[n];
- if (i == 0)
- regs->orig_gpr2 = args[0];
+ if (n > 0)
+ regs->gprs[2 + n] = args[n];
+ regs->orig_gpr2 = args[0];
}

static inline int syscall_get_arch(void)
diff --git a/arch/sh/include/asm/syscall_32.h b/arch/sh/include/asm/syscall_32.h
index 2bf1199a0595..8c9d7e5e5dcc 100644
--- a/arch/sh/include/asm/syscall_32.h
+++ b/arch/sh/include/asm/syscall_32.h
@@ -62,23 +62,14 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- /* Same note as above applies */
- BUG_ON(i);
-
- switch (n) {
- case 6: regs->regs[1] = args[5];
- case 5: regs->regs[0] = args[4];
- case 4: regs->regs[7] = args[3];
- case 3: regs->regs[6] = args[2];
- case 2: regs->regs[5] = args[1];
- case 1: regs->regs[4] = args[0];
- break;
- default:
- BUG();
- }
+ regs->regs[1] = args[5];
+ regs->regs[0] = args[4];
+ regs->regs[7] = args[3];
+ regs->regs[6] = args[2];
+ regs->regs[5] = args[1];
+ regs->regs[4] = args[0];
}

static inline int syscall_get_arch(void)
diff --git a/arch/sh/include/asm/syscall_64.h b/arch/sh/include/asm/syscall_64.h
index 4e8f6460c703..22fad97da066 100644
--- a/arch/sh/include/asm/syscall_64.h
+++ b/arch/sh/include/asm/syscall_64.h
@@ -54,11 +54,9 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- BUG_ON(i + n > 6);
- memcpy(&regs->regs[2 + i], args, n * sizeof(args[0]));
+ memcpy(&regs->regs[2], args, 6 * sizeof(args[0]));
}

static inline int syscall_get_arch(void)
diff --git a/arch/sparc/include/asm/syscall.h b/arch/sparc/include/asm/syscall.h
index 872dfee852d6..4d075434e816 100644
--- a/arch/sparc/include/asm/syscall.h
+++ b/arch/sparc/include/asm/syscall.h
@@ -119,13 +119,12 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
- unsigned int j;
+ unsigned int i;

- for (j = 0; j < n; j++)
- regs->u_regs[UREG_I0 + i + j] = args[j];
+ for (i = 0; i < 6; i++)
+ regs->u_regs[UREG_I0 + i] = args[i];
}

static inline int syscall_get_arch(void)
diff --git a/arch/um/include/asm/syscall-generic.h b/arch/um/include/asm/syscall-generic.h
index 25d00acd1322..98e50c50c12e 100644
--- a/arch/um/include/asm/syscall-generic.h
+++ b/arch/um/include/asm/syscall-generic.h
@@ -67,43 +67,16 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
struct uml_pt_regs *r = &regs->regs;

- switch (i) {
- case 0:
- if (!n--)
- break;
- UPT_SYSCALL_ARG1(r) = *args++;
- case 1:
- if (!n--)
- break;
- UPT_SYSCALL_ARG2(r) = *args++;
- case 2:
- if (!n--)
- break;
- UPT_SYSCALL_ARG3(r) = *args++;
- case 3:
- if (!n--)
- break;
- UPT_SYSCALL_ARG4(r) = *args++;
- case 4:
- if (!n--)
- break;
- UPT_SYSCALL_ARG5(r) = *args++;
- case 5:
- if (!n--)
- break;
- UPT_SYSCALL_ARG6(r) = *args++;
- case 6:
- if (!n--)
- break;
- default:
- BUG();
- break;
- }
+ UPT_SYSCALL_ARG1(r) = *args++;
+ UPT_SYSCALL_ARG2(r) = *args++;
+ UPT_SYSCALL_ARG3(r) = *args++;
+ UPT_SYSCALL_ARG4(r) = *args++;
+ UPT_SYSCALL_ARG5(r) = *args++;
+ UPT_SYSCALL_ARG6(r) = *args;
}

/* See arch/x86/um/asm/syscall.h for syscall_get_arch() definition. */
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
index 8dbb5c379450..4c305471ec33 100644
--- a/arch/x86/include/asm/syscall.h
+++ b/arch/x86/include/asm/syscall.h
@@ -138,63 +138,26 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
# ifdef CONFIG_IA32_EMULATION
- if (task->thread_info.status & TS_COMPAT)
- switch (i) {
- case 0:
- if (!n--) break;
- regs->bx = *args++;
- case 1:
- if (!n--) break;
- regs->cx = *args++;
- case 2:
- if (!n--) break;
- regs->dx = *args++;
- case 3:
- if (!n--) break;
- regs->si = *args++;
- case 4:
- if (!n--) break;
- regs->di = *args++;
- case 5:
- if (!n--) break;
- regs->bp = *args++;
- case 6:
- if (!n--) break;
- default:
- BUG();
- break;
- }
- else
+ if (task->thread_info.status & TS_COMPAT) {
+ regs->bx = *args++;
+ regs->cx = *args++;
+ regs->dx = *args++;
+ regs->si = *args++;
+ regs->di = *args++;
+ regs->bp = *args;
+ } else
# endif
- switch (i) {
- case 0:
- if (!n--) break;
- regs->di = *args++;
- case 1:
- if (!n--) break;
- regs->si = *args++;
- case 2:
- if (!n--) break;
- regs->dx = *args++;
- case 3:
- if (!n--) break;
- regs->r10 = *args++;
- case 4:
- if (!n--) break;
- regs->r8 = *args++;
- case 5:
- if (!n--) break;
- regs->r9 = *args++;
- case 6:
- if (!n--) break;
- default:
- BUG();
- break;
- }
+ {
+ regs->di = *args++;
+ regs->si = *args++;
+ regs->dx = *args++;
+ regs->r10 = *args++;
+ regs->r8 = *args++;
+ regs->r9 = *args;
+ }
}

static inline int syscall_get_arch(void)
diff --git a/arch/xtensa/include/asm/syscall.h b/arch/xtensa/include/asm/syscall.h
index 1504ce9a233a..91dc06d58060 100644
--- a/arch/xtensa/include/asm/syscall.h
+++ b/arch/xtensa/include/asm/syscall.h
@@ -70,24 +70,13 @@ static inline void syscall_get_arguments(struct task_struct *task,

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args)
{
static const unsigned int reg[] = XTENSA_SYSCALL_ARGUMENT_REGS;
- unsigned int j;
-
- if (n == 0)
- return;
-
- if (WARN_ON_ONCE(i + n > SYSCALL_MAX_ARGS)) {
- if (i < SYSCALL_MAX_ARGS)
- n = SYSCALL_MAX_ARGS - i;
- else
- return;
- }
+ unsigned int i;

- for (j = 0; j < n; ++j)
- regs->areg[reg[i + j]] = args[j];
+ for (i = 0; i < 6; ++i)
+ regs->areg[reg[i]] = args[i];
}

asmlinkage long xtensa_rt_sigreturn(struct pt_regs*);
diff --git a/include/asm-generic/syscall.h b/include/asm-generic/syscall.h
index 269e9412ef42..b88239e9efe4 100644
--- a/include/asm-generic/syscall.h
+++ b/include/asm-generic/syscall.h
@@ -120,21 +120,15 @@ void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
* syscall_set_arguments - change system call parameter value
* @task: task of interest, must be in system call entry tracing
* @regs: task_pt_regs() of @task
- * @i: argument index [0,5]
- * @n: number of arguments; n+i must be [1,6].
* @args: array of argument values to store
*
- * Changes @n arguments to the system call starting with the @i'th argument.
- * Argument @i gets value @args[0], and so on.
- * An arch inline version is probably optimal when @i and @n are constants.
+ * Changes 6 arguments to the system call.
+ * The first argument gets value @args[0], and so on.
*
* It's only valid to call this when @task is stopped for tracing on
* entry to a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
- * It's invalid to call this with @i + @n > 6; we only support system calls
- * taking up to 6 arguments.
*/
void syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
- unsigned int i, unsigned int n,
const unsigned long *args);

/**
--
2.20.1



2019-04-04 07:54:53

by Thomas Gleixner

[permalink] [raw]
Subject: Re: [PATCH 6/6 v3] syscalls: Remove start and number from syscall_set_arguments() args

On Mon, 1 Apr 2019, Steven Rostedt wrote:

> From: "Steven Rostedt (VMware)" <[email protected]>
>
> After removing the start and count arguments of syscall_get_arguments() it
> seems reasonable to remove them from syscall_set_arguments(). Note, as of
> today, there are no users of syscall_set_arguments(). But we are told that
> there will be soon. But for now, at least make it consistent with
> syscall_get_arguments().
>
> Link: http://lkml.kernel.org/r/[email protected]

For x86:

Reviewed-by: Thomas Gleixner <[email protected]>

2019-04-04 18:56:35

by Max Filippov

[permalink] [raw]
Subject: Re: [PATCH 6/6 v3] syscalls: Remove start and number from syscall_set_arguments() args

On Mon, Apr 1, 2019 at 6:45 AM Steven Rostedt <[email protected]> wrote:
>
> From: "Steven Rostedt (VMware)" <[email protected]>
>
> After removing the start and count arguments of syscall_get_arguments() it
> seems reasonable to remove them from syscall_set_arguments(). Note, as of
> today, there are no users of syscall_set_arguments(). But we are told that
> there will be soon. But for now, at least make it consistent with
> syscall_get_arguments().

[...]

> arch/xtensa/include/asm/syscall.h | 17 ++-----

For xtensa changes:
Acked-by: Max Filippov <[email protected]>

--
Thanks.
-- Max

2019-04-04 20:21:04

by Dmitry V. Levin

[permalink] [raw]
Subject: Re: [PATCH 6/6 v3] syscalls: Remove start and number from syscall_set_arguments() args

On Mon, Apr 01, 2019 at 09:41:10AM -0400, Steven Rostedt wrote:
> From: "Steven Rostedt (VMware)" <[email protected]>
>
> After removing the start and count arguments of syscall_get_arguments() it
> seems reasonable to remove them from syscall_set_arguments(). Note, as of
> today, there are no users of syscall_set_arguments(). But we are told that
> there will be soon. But for now, at least make it consistent with
> syscall_get_arguments().
>
> Link: http://lkml.kernel.org/r/[email protected]

FWIW, you can add
Reviewed-by: Dmitry V. Levin <[email protected]>

There are two places listed below where I'd prefer to see more readable
equivalents, but feel free to leave it to respective arch maintainers.

> diff --git a/arch/nds32/include/asm/syscall.h b/arch/nds32/include/asm/syscall.h
> index 89a6ec8731d8..671ebd357496 100644
> --- a/arch/nds32/include/asm/syscall.h
> +++ b/arch/nds32/include/asm/syscall.h
> @@ -129,39 +129,20 @@ void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> * syscall_set_arguments - change system call parameter value
> * @task: task of interest, must be in system call entry tracing
> * @regs: task_pt_regs() of @task
> - * @i: argument index [0,5]
> - * @n: number of arguments; n+i must be [1,6].
> * @args: array of argument values to store
> *
> - * Changes @n arguments to the system call starting with the @i'th argument.
> - * Argument @i gets value @args[0], and so on.
> - * An arch inline version is probably optimal when @i and @n are constants.
> + * Changes 6 arguments to the system call. The first argument gets value
> + * @args[0], and so on.
> *
> * It's only valid to call this when @task is stopped for tracing on
> * entry to a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT.
> - * It's invalid to call this with @i + @n > 6; we only support system calls
> - * taking up to 6 arguments.
> */
> void syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
> - unsigned int i, unsigned int n,
> const unsigned long *args)
> {
> - if (n == 0)
> - return;
> -
> - if (i + n > SYSCALL_MAX_ARGS) {
> - pr_warn("%s called with max args %d, handling only %d\n",
> - __func__, i + n, SYSCALL_MAX_ARGS);
> - n = SYSCALL_MAX_ARGS - i;
> - }
> -
> - if (i == 0) {
> - regs->orig_r0 = args[0];
> - args++;
> - i++;
> - n--;
> - }
> + regs->orig_r0 = args[0];
> + args++;
>
> - memcpy(&regs->uregs[0] + i, args, n * sizeof(args[0]));
> + memcpy(&regs->uregs[0] + 1, args, 5 * sizeof(args[0]));
> }

A shorter and slightly more readable equivalent of the last memcpy is

memcpy(&regs->uregs[1], args, 5 * sizeof(args[0]));

> diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
> index ee0b1f6aa36d..59c3e91f2cdb 100644
> --- a/arch/s390/include/asm/syscall.h
> +++ b/arch/s390/include/asm/syscall.h
> @@ -74,15 +74,14 @@ static inline void syscall_get_arguments(struct task_struct *task,
>
> static inline void syscall_set_arguments(struct task_struct *task,
> struct pt_regs *regs,
> - unsigned int i, unsigned int n,
> const unsigned long *args)
> {
> - BUG_ON(i + n > 6);
> + unsigned int n = 6;
> +
> while (n-- > 0)
> - if (i + n > 0)
> - regs->gprs[2 + i + n] = args[n];
> - if (i == 0)
> - regs->orig_gpr2 = args[0];
> + if (n > 0)
> + regs->gprs[2 + n] = args[n];
> + regs->orig_gpr2 = args[0];
> }

A shorter and slightly more readable equivalent of the loop is

while (--n > 0)
regs->gprs[2 + n] = args[n];


--
ldv


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