linux

iv/linux

History

Sven Schnelle 3ec18fc783 parisc/entry: fix trace test in syscall exit path

commit 8779e05ba8aa ("parisc: Fix ptrace check on syscall return")
fixed testing of TI_FLAGS. This uncovered a bug in the test mask.
syscall_restore_rfi is only used when the kernel needs to exit to
usespace with single or block stepping and the recovery counter
enabled. The test however used _TIF_SYSCALL_TRACE_MASK, which
includes a lot of bits that shouldn't be tested here.

Fix this by using TIF_SINGLESTEP and TIF_BLOCKSTEP directly.

I encountered this bug by enabling syscall tracepoints. Both in qemu and
on real hardware. As soon as i enabled the tracepoint (sys_exit_read,
but i guess it doesn't really matter which one), i got random page
faults in userspace almost immediately.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>

2021-11-13 22:10:56 +01:00

boot

parisc: decompressor: clean up Makefile

2021-11-01 07:36:01 +01:00

configs

parisc: Update defconfigs

2021-11-01 07:36:02 +01:00

include

parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page

2021-11-13 22:10:56 +01:00

kernel

parisc/entry: fix trace test in syscall exit path