This is a note to let you know that I've just added the patch titled
s390/ptrace: return -ENOSYS when invalid syscall is supplied
to the 5.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
s390-ptrace-return-enosys-when-invalid-syscall-is-su.patch
and it can be found in the queue-5.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5ce966679d209a2cb74f22cc898ad721e7bc9fe6
Author: Sven Schnelle <svens@xxxxxxxxxxxxx>
Date: Fri Mar 6 13:18:31 2020 +0100
s390/ptrace: return -ENOSYS when invalid syscall is supplied
[ Upstream commit cd29fa798001075a554b978df3a64e6656c25794 ]
The current code returns the syscall number which an invalid
syscall number is supplied and tracing is enabled. This makes
the strace testsuite fail.
Signed-off-by: Sven Schnelle <svens@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 9eee345568890..3f29646313e82 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -838,6 +838,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
{
unsigned long mask = -1UL;
+ long ret = -1;
if (is_compat_task())
mask = 0xffffffff;
@@ -854,8 +855,7 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
* debugger stored an invalid system call number. Skip
* the system call and the system call restart handling.
*/
- clear_pt_regs_flag(regs, PIF_SYSCALL);
- return -1;
+ goto skip;
}
#ifdef CONFIG_SECCOMP
@@ -871,7 +871,7 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
sd.arch = AUDIT_ARCH_S390X;
}
- sd.nr = regs->gprs[2] & 0xffff;
+ sd.nr = regs->int_code & 0xffff;
sd.args[0] = regs->orig_gpr2 & mask;
sd.args[1] = regs->gprs[3] & mask;
sd.args[2] = regs->gprs[4] & mask;
@@ -880,19 +880,26 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
sd.args[5] = regs->gprs[7] & mask;
if (__secure_computing(&sd) == -1)
- return -1;
+ goto skip;
}
#endif /* CONFIG_SECCOMP */
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
- trace_sys_enter(regs, regs->gprs[2]);
+ trace_sys_enter(regs, regs->int_code & 0xffff);
- audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
+ audit_syscall_entry(regs->int_code & 0xffff, regs->orig_gpr2 & mask,
regs->gprs[3] &mask, regs->gprs[4] &mask,
regs->gprs[5] &mask);
+ if ((signed long)regs->gprs[2] >= NR_syscalls) {
+ regs->gprs[2] = -ENOSYS;
+ ret = -ENOSYS;
+ }
return regs->gprs[2];
+skip:
+ clear_pt_regs_flag(regs, PIF_SYSCALL);
+ return ret;
}
asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
