syscall_get_nr() is defined to return -1 for a non-system call or a
ptrace/seccomp restart; not just any arbitrary number. See comment in
<asm-generic/syscall.h> for the official definition of this function.
Signed-off-by: H. Peter Anvin <[email protected]>
---
arch/x86/kernel/ptrace.c | 2 +-
arch/x86/kernel/signal.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 87a4143aa7d7..4c208ea3bd9f 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -911,7 +911,7 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 value)
* syscall with TS_COMPAT still set.
*/
regs->orig_ax = value;
- if (syscall_get_nr(child, regs) >= 0)
+ if (syscall_get_nr(child, regs) != -1)
child->thread_info.status |= TS_I386_REGS_POKED;
break;
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index a06cb107c0e8..e12779a2714d 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -713,7 +713,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs)
save_v86_state((struct kernel_vm86_regs *) regs, VM86_SIGNAL);
/* Are we from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
+ if (syscall_get_nr(current, regs) != -1) {
/* If so, check system call restarting.. */
switch (syscall_get_error(current, regs)) {
case -ERESTART_RESTARTBLOCK:
@@ -793,7 +793,7 @@ void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)
}
/* Did we come from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
+ if (syscall_get_nr(current, regs) != -1) {
/* Restart the system call - no handlers present */
switch (syscall_get_error(current, regs)) {
case -ERESTARTNOHAND:
--
2.31.1
The following commit has been merged into the x86/asm branch of tip:
Commit-ID: 9ddcb87b9218dec760e8d8a780bc8ad514c3d36a
Gitweb: https://git.kernel.org/tip/9ddcb87b9218dec760e8d8a780bc8ad514c3d36a
Author: H. Peter Anvin <[email protected]>
AuthorDate: Mon, 10 May 2021 11:53:15 -07:00
Committer: Ingo Molnar <[email protected]>
CommitterDate: Wed, 12 May 2021 10:49:15 +02:00
x86/regs: Syscall_get_nr() returns -1 for a non-system call
syscall_get_nr() is defined to return -1 for a non-system call or a
ptrace/seccomp restart; not just any arbitrary number. See comment in
<asm-generic/syscall.h> for the official definition of this function.
Signed-off-by: H. Peter Anvin <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
arch/x86/kernel/ptrace.c | 2 +-
arch/x86/kernel/signal.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 87a4143..4c208ea 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -911,7 +911,7 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 value)
* syscall with TS_COMPAT still set.
*/
regs->orig_ax = value;
- if (syscall_get_nr(child, regs) >= 0)
+ if (syscall_get_nr(child, regs) != -1)
child->thread_info.status |= TS_I386_REGS_POKED;
break;
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index a06cb10..e12779a 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -713,7 +713,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs)
save_v86_state((struct kernel_vm86_regs *) regs, VM86_SIGNAL);
/* Are we from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
+ if (syscall_get_nr(current, regs) != -1) {
/* If so, check system call restarting.. */
switch (syscall_get_error(current, regs)) {
case -ERESTART_RESTARTBLOCK:
@@ -793,7 +793,7 @@ void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)
}
/* Did we come from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
+ if (syscall_get_nr(current, regs) != -1) {
/* Restart the system call - no handlers present */
switch (syscall_get_error(current, regs)) {
case -ERESTARTNOHAND: