On Mon, Dec 16, 2024 at 4:26 PM James Carter <jwcart2@xxxxxxxxx> wrote: > > On Fri, Nov 29, 2024 at 6:05 AM Christian Göttsche > <cgoettsche@xxxxxxxxxxxxx> wrote: > > > > From: Steve Langasek <steve.langasek@xxxxxxxxxxxxx> > > > > Maintains the type signature of the existing matchpathcon_filespec_add() > > entry point on 32-bit archs but maps the API to a new > > matchpathcon_filespec_add64() entry point that takes a 64-bit ino_t argument > > instead. > > > > Software on 32-bit Linux ports which historically use a 32-bit time_t (thus > > affected by the y2038 problem) have, as a precondition of migrating to > > 64-bit time_t, that they also migrate to large filesystem support because > > glibc does not provide entry points for the cross-product of > > (LFS: yes, LFS: no) x (time_t: 32, time_t: 64). > > > > In order to support smooth migration of such operating systems from 32-bit > > time_t to 64-bit time_t, it is useful for libselinux to: > > > > - provide entry points on 32-bit systems for both LFS and non-LFS variants > > of the API (as glibc itself does) > > - use LFS internally for all filesystem calls (just in case) > > - map the API call to the correct implementation based on the build > > environment of the caller. > > > > Signed-off-by: Steve Langasek <steve.langasek@xxxxxxxxxxxxx> > > Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx> > > --- > > Originally posted https://lore.kernel.org/selinux/ZeQuOBwQ2eSbkUAS@xxxxxxxxxxxxxxx/1.2-0001-Always-build-for-LFS-mode-on-32-bit-archs.patch > > > > v2: > > - Adjusted version in libselinux.map > > - check for __BITS_PER_LONG availability in matchpathcon.c similar to > > selinux.h > > - add static asserts, it's better to fail hard at compile time instead > > of having a silent ABI break > > Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx> > > Acked-by: James Carter <jwcart2@xxxxxxxxx> > Merged. Thanks, Jim > > --- > > libselinux/Makefile | 6 ++++++ > > libselinux/include/selinux/selinux.h | 5 +++++ > > libselinux/src/Makefile | 2 ++ > > libselinux/src/libselinux.map | 5 +++++ > > libselinux/src/matchpathcon.c | 26 ++++++++++++++++++++++++++ > > libselinux/utils/Makefile | 2 ++ > > 6 files changed, 46 insertions(+) > > > > diff --git a/libselinux/Makefile b/libselinux/Makefile > > index 6d9e2736..a50b6491 100644 > > --- a/libselinux/Makefile > > +++ b/libselinux/Makefile > > @@ -34,6 +34,12 @@ PCRE_CFLAGS += $(shell $(PKG_CONFIG) --cflags $(PCRE_MODULE)) > > PCRE_LDLIBS := $(shell $(PKG_CONFIG) --libs $(PCRE_MODULE)) > > export PCRE_MODULE PCRE_CFLAGS PCRE_LDLIBS > > > > +USE_LFS ?= y > > +ifeq ($(USE_LFS),y) > > + LFS_CFLAGS := -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 > > +endif > > +export LFS_CFLAGS > > + > > OS := $(shell uname) > > export OS > > > > diff --git a/libselinux/include/selinux/selinux.h b/libselinux/include/selinux/selinux.h > > index 50419a7c..f3cf5a20 100644 > > --- a/libselinux/include/selinux/selinux.h > > +++ b/libselinux/include/selinux/selinux.h > > @@ -1,8 +1,10 @@ > > #ifndef _SELINUX_H_ > > #define _SELINUX_H_ > > > > +#include <stdint.h> > > #include <sys/types.h> > > #include <stdarg.h> > > +#include <asm/bitsperlong.h> > > > > #ifdef __cplusplus > > extern "C" { > > @@ -535,6 +537,9 @@ extern int matchpathcon_index(const char *path, > > with the same inode (e.g. due to multiple hard links). If so, then > > use the latter of the two specifications based on their order in the > > file contexts configuration. Return the used specification index. */ > > +#if defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64 && __BITS_PER_LONG < 64 > > +#define matchpathcon_filespec_add matchpathcon_filespec_add64 > > +#endif > > extern int matchpathcon_filespec_add(ino_t ino, int specind, const char *file); > > > > /* Destroy any inode associations that have been added, e.g. to restart > > diff --git a/libselinux/src/Makefile b/libselinux/src/Makefile > > index 41cfbdca..9909eb40 100644 > > --- a/libselinux/src/Makefile > > +++ b/libselinux/src/Makefile > > @@ -89,6 +89,8 @@ CFLAGS ?= -O -Wall -W -Wundef -Wformat-y2k -Wformat-security -Winit-self -Wmissi > > -Werror -Wno-aggregate-return \ > > $(EXTRA_CFLAGS) > > > > +override CFLAGS += $(LFS_CFLAGS) > > + > > LD_SONAME_FLAGS=-soname,$(LIBSO),--version-script=libselinux.map,-z,defs,-z,relro > > > > ifeq ($(OS), Darwin) > > diff --git a/libselinux/src/libselinux.map b/libselinux/src/libselinux.map > > index 5e00f45b..02f5b761 100644 > > --- a/libselinux/src/libselinux.map > > +++ b/libselinux/src/libselinux.map > > @@ -252,3 +252,8 @@ LIBSELINUX_3.5 { > > getpidprevcon; > > getpidprevcon_raw; > > } LIBSELINUX_3.4; > > + > > +LIBSELINUX_3.8 { > > + global: > > + matchpathcon_filespec_add64; > > +} LIBSELINUX_3.5; > > diff --git a/libselinux/src/matchpathcon.c b/libselinux/src/matchpathcon.c > > index 967520e4..15f9353d 100644 > > --- a/libselinux/src/matchpathcon.c > > +++ b/libselinux/src/matchpathcon.c > > @@ -1,3 +1,4 @@ > > +#include <assert.h> > > #include <sys/stat.h> > > #include <string.h> > > #include <errno.h> > > @@ -261,6 +262,31 @@ int matchpathcon_filespec_add(ino_t ino, int specind, const char *file) > > return -1; > > } > > > > +#if defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64 && __BITS_PER_LONG < 64 > > +/* alias defined in the public header but we undefine it here */ > > +#undef matchpathcon_filespec_add > > + > > +/* ABI backwards-compatible shim for non-LFS 32-bit systems */ > > + > > +static_assert(sizeof(unsigned long) == sizeof(__ino_t), "inode size mismatch"); > > +static_assert(sizeof(unsigned long) == sizeof(uint32_t), "inode size mismatch"); > > +static_assert(sizeof(ino_t) == sizeof(ino64_t), "inode size mismatch"); > > +static_assert(sizeof(ino64_t) == sizeof(uint64_t), "inode size mismatch"); > > + > > +extern int matchpathcon_filespec_add(unsigned long ino, int specind, > > + const char *file); > > + > > +int matchpathcon_filespec_add(unsigned long ino, int specind, > > + const char *file) > > +{ > > + return matchpathcon_filespec_add64(ino, specind, file); > > +} > > +#else > > + > > +static_assert(sizeof(unsigned long) == sizeof(ino_t), "inode size mismatch"); > > + > > +#endif > > + > > /* > > * Evaluate the association hash table distribution. > > */ > > diff --git a/libselinux/utils/Makefile b/libselinux/utils/Makefile > > index f3cedc11..0d7095b1 100644 > > --- a/libselinux/utils/Makefile > > +++ b/libselinux/utils/Makefile > > @@ -36,6 +36,8 @@ CFLAGS ?= -O -Wall -W -Wundef -Wformat-y2k -Wformat-security -Winit-self -Wmissi > > -Werror -Wno-aggregate-return -Wno-redundant-decls -Wstrict-overflow=5 \ > > $(EXTRA_CFLAGS) > > > > +override CFLAGS += $(LFS_CFLAGS) > > + > > ifeq ($(OS), Darwin) > > override CFLAGS += -I/opt/local/include -I../../libsepol/include > > override LDFLAGS += -L../../libsepol/src -undefined dynamic_lookup > > -- > > 2.45.2 > > > >
