linux: fix handling of out-of-bounds syscall attempts
Due to an off by one the code would read an entry past the table, as
opposed to the last entry which contains the nosys handler.
This fixes my fault.
MFC r289058 (by cem@):
Fix missing semi-colon from r289055.
MFC r289768 (by jhb@):
Merge r289055 to amd64/linux32:
linux: fix handling of out-of-bounds syscall attempts
Due to an off by one the code would read an entry past the table, as
opposed to the last entry which contains the nosys handler.
When I merged the lemul branch I missied kib@'s r282708 commit.
This is not the final fix as I need properly cleanup thread resources
before other threads suicide.
Rework signal code to allow using it by other modules, like linprocfs:
1. Linux sigset always 64 bit on all platforms. In order to move Linux
sigset code to the linux_common module define it as 64 bit int. Move
Linux sigset manipulation routines to the MI path.
2. Move Linux signal number definitions to the MI path. In general, they
are the same on all platforms except for a few signals.
3. Map Linux RT signals to the FreeBSD RT signals and hide signal conversion
tables to avoid conversion errors.
4. Emulate Linux SIGPWR signal via FreeBSD SIGRTMIN signal which is outside
of allowed on Linux signal numbers.
PR: 197216
According to Linux man sigaltstack(3) shall return EINVAL if the ss
argument is not a null pointer, and the ss_flags member pointed to by ss
contains flags other than SS_DISABLE. However, in fact, Linux also
allows SS_ONSTACK flag which is simply ignored.
For buggy apps (at least mono) ignore other than SS_DISABLE
flags as a Linux do.
While here move MI part of sigaltstack code to the appropriate place.
Implement epoll family system calls. This is a tiny wrapper
around kqueue() to implement epoll subset of functionality.
The kqueue user data are 32bit on i386 which is not enough for
epoll user data, so we keep user data in the proc emuldata.
Initial patch developed by rdivacky@ in 2007, then extended
by Yuri Victorovich @ r255672 and finished by me
in collaboration with mjg@ and jillies@.
Being exported through vdso the note.Linux section used by glibc
to determine the kernel version (this saves one uname call).
Temporarily disable the export of a note.Linux section until I figured
out how to change the kernel version in the note.Linux on the fly.
Change linux faccessat syscall definition to match actual linux one.
The AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented
within the glibc wrapper function for faccessat(). If either of these
flags are specified, then the wrapper function employs fstatat() to
determine access permissions.
Refund the proc emuldata struct for future use. For now move flags from
thread emuldata to proc emuldata as it was originally intended.
As we can have both 64 & 32 bit Linuxulator running any eventhandler
can be called twice for us. To prevent this move eventhandlers code
from linux_emul.c to the linux_common.ko module.
Introduce a new module linux_common.ko which is intended for the
following primary purposes:
1. Remove the dependency of linsysfs and linprocfs modules from linux.ko,
which will be architecture specific on amd64.
2. Incorporate into linux_common.ko general code for platforms on which
we'll support two Linuxulator modules (for both instruction set - 32 & 64 bit).
3. Move malloc(9) declaration to linux_common.ko, to enable getting memory
usage statistics properly.
Currently linux_common.ko incorporates a code from linux_mib.c and linux_util.c
and linprocfs, linsysfs and linux kernel modules depend on linux_common.ko.
Temporarily remove dtrace garbage from linux_mib.c and linux_util.c
Implement vdso - virtual dynamic shared object. Through vdso Linux
exposes functions from kernel with proper DWARF CFI information so that
it becomes easier to unwind through them.
Using vdso is a mandatory for a thread cancelation && cleanup
on a modern glibc.