From 01bfa1fc30bd5715918c44a1b226d43c9491a0ae Mon Sep 17 00:00:00 2001 From: Luca Dariz Date: Sun, 3 Apr 2022 17:00:19 +0200 Subject: add separate port_size and mach_port_name_size definitions * cpu.sym: retrieve size of vm_offset_t and mach_port_name_t from gnumach headers at compile type. * global.{c,h}: add port size as a variable and initialize it to the port name size. * lexxer.l: apply port or port name size to the corresponding types, instead of using the word size. * parser.y: update port size if we're generating for kernel-space (server or client). Also re-initialize default port types to account for this change. * type.c: use port size instead of word size in default port types and runtime checks. There are many assumptions about mach_port_t: - on kernel side, its size is the same as a pointer. This allows to replace the port name with the address of the corresponding data structure during copyin in mach_msg() - in mig, this is also the "word size", which is derived from gnumach headers as the size of integer_t - its size is also the same as natural_t, so it's possible to model structures like mach_port_status_t as an array of integer_t in mig. This is convenient since arrays and structures can't have mixed types. - its size is always the same as the port name size This patch does not change the current behaviour on 32-bit kernels, but allows for some of these assumptions to be broken on 64-bit kernels. This is needed to have 32-bit port names on 64-bit kernels and be able to support a 32-bit userspace. It still leaves the choice for a 64-bit userspace, if all integer_t and natural_t are to be extended to 64 bit. However keeping 32-bit port names seems to be the right thing, based on previous discussions [1], even for a 64-bit kernel. The only assumption kept is that in kernel-space ports are always the size of a pointer, as they refer to a data structure and not to a specific port name. To ensure this is true for various user/kernel combinations, we dynamically change the port size if we're generating code for kernel-space server or clients, and keep the size of a port the same of a port name for user-space servers and clients. [1] https://lists.gnu.org/archive/html/bug-hurd/2012-04/msg00000.html Signed-off-by: Luca Dariz Message-Id: <20220403150020.120799-2-luca@orpolo.org> --- type.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'type.c') diff --git a/type.c b/type.c index eb88cf4..86137ae 100644 --- a/type.c +++ b/type.c @@ -848,7 +848,7 @@ init_type(void) itRequestPortType->itInNameStr = "MACH_MSG_TYPE_COPY_SEND"; itRequestPortType->itOutName = MACH_MSG_TYPE_PORT_SEND; itRequestPortType->itOutNameStr = "MACH_MSG_TYPE_PORT_SEND"; - itRequestPortType->itSize = word_size_in_bits; + itRequestPortType->itSize = port_size_in_bits; itCalculateSizeInfo(itRequestPortType); itCalculateNameInfo(itRequestPortType); @@ -858,7 +858,7 @@ init_type(void) itZeroReplyPortType->itInNameStr = "0"; itZeroReplyPortType->itOutName = 0; itZeroReplyPortType->itOutNameStr = "0"; - itZeroReplyPortType->itSize = word_size_in_bits; + itZeroReplyPortType->itSize = port_size_in_bits; itCalculateSizeInfo(itZeroReplyPortType); itCalculateNameInfo(itZeroReplyPortType); @@ -868,7 +868,7 @@ init_type(void) itRealReplyPortType->itInNameStr = "MACH_MSG_TYPE_MAKE_SEND_ONCE"; itRealReplyPortType->itOutName = MACH_MSG_TYPE_PORT_SEND_ONCE; itRealReplyPortType->itOutNameStr = "MACH_MSG_TYPE_PORT_SEND_ONCE"; - itRealReplyPortType->itSize = word_size_in_bits; + itRealReplyPortType->itSize = port_size_in_bits; itCalculateSizeInfo(itRealReplyPortType); itCalculateNameInfo(itRealReplyPortType); @@ -906,7 +906,7 @@ itCheckRequestPortType(identifier_t name, const ipc_type_t *it) (it->itOutName != MACH_MSG_TYPE_PORT_SEND_ONCE) && (it->itOutName != MACH_MSG_TYPE_POLYMORPHIC)) || (it->itNumber != 1) || - (it->itSize != word_size_in_bits) || + (it->itSize != port_size_in_bits) || !it->itInLine || it->itDeallocate != d_NO || !it->itStruct || @@ -927,7 +927,7 @@ itCheckReplyPortType(identifier_t name, const ipc_type_t *it) (it->itOutName != MACH_MSG_TYPE_POLYMORPHIC) && (it->itOutName != 0)) || (it->itNumber != 1) || - (it->itSize != word_size_in_bits) || + (it->itSize != port_size_in_bits) || !it->itInLine || it->itDeallocate != d_NO || !it->itStruct || -- cgit v1.2.3