7d94143291
When PTRACE_SYSCALL was used and then PTRACE_DETACH is used, the TIF_SYSCALL_TRACE flag is left set on the formerly-traced task. This means that when a new tracer comes along and does PTRACE_ATTACH, it's possible he gets a syscall tracing stop even though he's never used PTRACE_SYSCALL. This happens if the task was in the middle of a system call when the second PTRACE_ATTACH was done. The symptom is an unexpected SIGTRAP when the tracer thinks that only SIGSTOP should have been provoked by his ptrace calls so far. A few machines already fixed this in ptrace_disable (i386, ia64, m68k). But all other machines do not, and still have this bug. On x86_64, this constitutes a regression in IA32 compatibility support. Since all machines now use TIF_SYSCALL_TRACE for this, I put the clearing of TIF_SYSCALL_TRACE in the generic ptrace_detach code rather than adding it to every other machine's ptrace_disable. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| cpufreq | ||
| acpi-ext.c | ||
| acpi-processor.c | ||
| acpi.c | ||
| asm-offsets.c | ||
| audit.c | ||
| brl_emu.c | ||
| crash_dump.c | ||
| crash.c | ||
| cyclone.c | ||
| efi_stub.S | ||
| efi.c | ||
| entry.h | ||
| entry.S | ||
| err_inject.c | ||
| esi_stub.S | ||
| esi.c | ||
| fsys.S | ||
| fsyscall_gtod_data.h | ||
| gate-data.S | ||
| gate.lds.S | ||
| gate.S | ||
| head.S | ||
| ia64_ksyms.c | ||
| init_task.c | ||
| iosapic.c | ||
| irq_ia64.c | ||
| irq_lsapic.c | ||
| irq.c | ||
| ivt.S | ||
| jprobes.S | ||
| kprobes.c | ||
| machine_kexec.c | ||
| machvec.c | ||
| Makefile | ||
| mca_asm.S | ||
| mca_drv_asm.S | ||
| mca_drv.c | ||
| mca_drv.h | ||
| mca.c | ||
| minstate.h | ||
| module.c | ||
| msi_ia64.c | ||
| numa.c | ||
| pal.S | ||
| palinfo.c | ||
| patch.c | ||
| perfmon_default_smpl.c | ||
| perfmon_generic.h | ||
| perfmon_itanium.h | ||
| perfmon_mckinley.h | ||
| perfmon_montecito.h | ||
| perfmon.c | ||
| process.c | ||
| ptrace.c | ||
| relocate_kernel.S | ||
| sal.c | ||
| salinfo.c | ||
| semaphore.c | ||
| setup.c | ||
| sigframe.h | ||
| signal.c | ||
| smp.c | ||
| smpboot.c | ||
| sys_ia64.c | ||
| time.c | ||
| topology.c | ||
| traps.c | ||
| unaligned.c | ||
| uncached.c | ||
| unwind_decoder.c | ||
| unwind_i.h | ||
| unwind.c | ||
| vmlinux.lds.S | ||