From 9c858712dd8de7f72156c3cf780c6fc9e8c96bcc Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Fri, 6 Dec 2024 14:37:49 -0300 Subject: [PATCH] linux: Add mseal syscall support It as added on Linux 6.10 (8be7258aad44b5e25977a98db136f677fa6f4370) as way to block operations as unmaping, moving to another location, shrinking the size, expanding the size, or modifying to a pre-existent memory mapping. Although the systecall only work on 64 bit CPU, the entrypoint was added for all ABIs (since kernel might eventually implement it to additional ones and/or the abi can execute on a 64 bit kernel). Checked on x86_64-linux-gnu. --- NEWS | 4 +- manual/memory.texi | 69 +++++++++++++++ sysdeps/unix/sysv/linux/Makefile | 2 + sysdeps/unix/sysv/linux/Versions | 3 + sysdeps/unix/sysv/linux/aarch64/libc.abilist | 1 + sysdeps/unix/sysv/linux/alpha/libc.abilist | 1 + sysdeps/unix/sysv/linux/arc/libc.abilist | 1 + sysdeps/unix/sysv/linux/arm/be/libc.abilist | 1 + sysdeps/unix/sysv/linux/arm/le/libc.abilist | 1 + sysdeps/unix/sysv/linux/bits/mman-shared.h | 8 ++ sysdeps/unix/sysv/linux/csky/libc.abilist | 1 + sysdeps/unix/sysv/linux/hppa/libc.abilist | 1 + sysdeps/unix/sysv/linux/i386/libc.abilist | 1 + sysdeps/unix/sysv/linux/kernel-features.h | 8 ++ .../sysv/linux/loongarch/lp64/libc.abilist | 1 + .../sysv/linux/m68k/coldfire/libc.abilist | 1 + .../unix/sysv/linux/m68k/m680x0/libc.abilist | 1 + .../sysv/linux/microblaze/be/libc.abilist | 1 + .../sysv/linux/microblaze/le/libc.abilist | 1 + .../sysv/linux/mips/mips32/fpu/libc.abilist | 1 + .../sysv/linux/mips/mips64/n32/libc.abilist | 1 + .../sysv/linux/mips/mips64/n64/libc.abilist | 1 + sysdeps/unix/sysv/linux/or1k/libc.abilist | 1 + .../linux/powerpc/powerpc32/fpu/libc.abilist | 1 + .../powerpc/powerpc32/nofpu/libc.abilist | 1 + .../linux/powerpc/powerpc64/be/libc.abilist | 1 + .../linux/powerpc/powerpc64/le/libc.abilist | 1 + .../unix/sysv/linux/riscv/rv32/libc.abilist | 1 + .../unix/sysv/linux/riscv/rv64/libc.abilist | 1 + .../unix/sysv/linux/s390/s390-32/libc.abilist | 1 + .../unix/sysv/linux/s390/s390-64/libc.abilist | 1 + sysdeps/unix/sysv/linux/sh/be/libc.abilist | 1 + sysdeps/unix/sysv/linux/sh/le/libc.abilist | 1 + .../sysv/linux/sparc/sparc32/libc.abilist | 1 + .../sysv/linux/sparc/sparc64/libc.abilist | 1 + sysdeps/unix/sysv/linux/syscalls.list | 1 + sysdeps/unix/sysv/linux/tst-mseal-pkey.c | 84 +++++++++++++++++++ sysdeps/unix/sysv/linux/tst-mseal.c | 67 +++++++++++++++ .../unix/sysv/linux/x86_64/64/libc.abilist | 1 + .../unix/sysv/linux/x86_64/x32/libc.abilist | 1 + 40 files changed, 276 insertions(+), 1 deletion(-) create mode 100644 sysdeps/unix/sysv/linux/tst-mseal-pkey.c create mode 100644 sysdeps/unix/sysv/linux/tst-mseal.c diff --git a/NEWS b/NEWS index e2e40e141c..4732ec2522 100644 --- a/NEWS +++ b/NEWS @@ -9,7 +9,9 @@ Version 2.42 Major new features: - [Add new features here] +* On Linux, the mseal function has been added. It allows to seal memory + mappings to avoid further change during process execution such as protection + permissions, unmapping, moving to another location, or shrinking the size. Deprecated and removed features, and other changes affecting compatibility: diff --git a/manual/memory.texi b/manual/memory.texi index dc4621e2c5..f092ee4ce6 100644 --- a/manual/memory.texi +++ b/manual/memory.texi @@ -3072,6 +3072,75 @@ process memory, no matter how it was allocated. However, portable use of the function requires that it is only used with memory regions returned by @code{mmap} or @code{mmap64}. +@deftypefun int mseal (void *@var{address}, size_t @var{length}, unsigned long @var{flags}) +@standards{Linux, sys/mman.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} + +A successful call to the @code {mseal} function protects the memory +range @var{address} of @var{length} bytes, previous allocated with +@code{mmap} or @code{mremap}, against further metadata changes such +as: + +@itemize @bullet +@item +Unmapping, moving to another location, extending or shrinking the size, +via @code{munmap} and @code{mremap}. + +@item +Moving or expanding a different VMA into the current location, via +@code{mremap}. + +@item +Modifying the memory range with @code{mmap} along with flag @code{MAP_FIXED}. + +@item +Change the protection flags with @code{mprotect} or @code{pkey_mprotect}. Also +for certain destructive @code{madvise} behaviours (@code{MADV_DONTNEED}, +@code{MADV_FREE}, @code{MADV_DONTNEED_LOCKED}, and @code{MADV_WIPEONFORK}), +@code{mseal} only blocks the operation if the protection key associate with +the memory denies write. + +@item +Destructive behaviors on anonymous memory, such as @code{madvice} with +@code{MADV_DONTNEED}. +@end itemize + +The @var{address} must be an allocated virtual memory done by @code{mmap} +or @code{mremap}, and it must be page aligned. The end address (@var{address} +plus @var{length}) must be within an allocated virtual memory range. There +should be no unallocated memory between the start and end of address range. + +The @var{flags} is currently ununsed. + +The @code{mseal} function returns @math{0} on sucess and @math{-1} on +failure. + +The following @code{errno} error conditions are defined for this +function: + +@table @code +@item EPERM +The system blocked the operation, and the given address range is unmodified +without a partial update. This error is also returned when @code{mseal} +is issued on a 32 bit CPUs (the sealing is currently supported only on +64-bit CPUs, although 32 bit binaries running on 64 bit kernel is +supported). + +@item ENOMEM +Either the @var{address} is not allocated, or the end address is not within the +allocation, or there is an unallocated memory between start and end address. + +@item ENOSYS +The kernel does not support the @code{mseal} syscall. + +@strong{NB:} The memory sealing changes the lifetime of a mapping, where the +sealing memory could not be unmapped until the process terminates or replaces +the process image through @code{execve} function. The sealed mappings are +inherited through @code{fork}. + +@end table +@end deftypefun + @subsection Memory Protection Keys @cindex memory protection key diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index 395d2d6593..ae46e0726d 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -213,6 +213,8 @@ tests += \ tst-misalign-clone \ tst-mlock2 \ tst-mount \ + tst-mseal \ + tst-mseal-pkey \ tst-ntp_adjtime \ tst-ntp_gettime \ tst-ntp_gettimex \ diff --git a/sysdeps/unix/sysv/linux/Versions b/sysdeps/unix/sysv/linux/Versions index 55d565545a..e5d226165e 100644 --- a/sysdeps/unix/sysv/linux/Versions +++ b/sysdeps/unix/sysv/linux/Versions @@ -332,6 +332,9 @@ libc { sched_getattr; sched_setattr; } + GLIBC_2.42 { + mseal; + } GLIBC_PRIVATE { # functions used in other libraries __syscall_rt_sigqueueinfo; diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist index 38db77e4f7..eab487fc76 100644 --- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist +++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist @@ -2750,3 +2750,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist index 637bfce9fb..d6d3464c46 100644 --- a/sysdeps/unix/sysv/linux/alpha/libc.abilist +++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist @@ -3097,6 +3097,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist index 4a305cf730..2c7aa2c939 100644 --- a/sysdeps/unix/sysv/linux/arc/libc.abilist +++ b/sysdeps/unix/sysv/linux/arc/libc.abilist @@ -2511,3 +2511,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist index 1d54f71b14..54fd3d3a83 100644 --- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist @@ -2803,6 +2803,7 @@ GLIBC_2.4 xprt_register F GLIBC_2.4 xprt_unregister F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist index ff7e8bc40b..4231ef1ffd 100644 --- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist @@ -2800,6 +2800,7 @@ GLIBC_2.4 xprt_register F GLIBC_2.4 xprt_unregister F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/bits/mman-shared.h b/sysdeps/unix/sysv/linux/bits/mman-shared.h index 31590979b9..b9892f62c2 100644 --- a/sysdeps/unix/sysv/linux/bits/mman-shared.h +++ b/sysdeps/unix/sysv/linux/bits/mman-shared.h @@ -81,6 +81,14 @@ int pkey_free (int __key) __THROW; range. */ int pkey_mprotect (void *__addr, size_t __len, int __prot, int __pkey) __THROW; +/* Seal the address range to avoid further modifications, such as remmap to + shrink or expand the VMA, change protection permission with mprotect, + unmap with munmap, destructive semantic such madvise with MADV_DONTNEED. + The address range must be valid VMA, withouth any gap (unallocated memory) + between start and end, and ADDR much be page aligned (LEN will be page + aligned implicitly). */ +int mseal (void *__addr, size_t __len, unsigned long flags) __THROW; + __END_DECLS #endif /* __USE_GNU */ diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist index c3ed65467d..53265587ca 100644 --- a/sysdeps/unix/sysv/linux/csky/libc.abilist +++ b/sysdeps/unix/sysv/linux/csky/libc.abilist @@ -2787,3 +2787,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist index 991475380c..2ad9eb1286 100644 --- a/sysdeps/unix/sysv/linux/hppa/libc.abilist +++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist @@ -2824,6 +2824,7 @@ GLIBC_2.4 unshare F GLIBC_2.41 cacheflush F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist index 4fedf775d4..f808d3f110 100644 --- a/sysdeps/unix/sysv/linux/i386/libc.abilist +++ b/sysdeps/unix/sysv/linux/i386/libc.abilist @@ -3007,6 +3007,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index 86b2d3ce51..a44824991f 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -257,4 +257,12 @@ # define __ASSUME_FCHMODAT2 0 #endif +/* The mseal system call was introduced across all architectures in Linux 6.10 + (although only supported on 64-bit CPUs). */ +#if __LINUX_KERNEL_VERSION >= 0x060A00 +# define __ASSUME_MSEAL 1 +#else +# define __ASSUME_MSEAL 0 +#endif + #endif /* kernel-features.h */ diff --git a/sysdeps/unix/sysv/linux/loongarch/lp64/libc.abilist b/sysdeps/unix/sysv/linux/loongarch/lp64/libc.abilist index 0024282289..db7a5896ff 100644 --- a/sysdeps/unix/sysv/linux/loongarch/lp64/libc.abilist +++ b/sysdeps/unix/sysv/linux/loongarch/lp64/libc.abilist @@ -2271,3 +2271,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist index 142595eb3e..91250faca5 100644 --- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist +++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist @@ -2783,6 +2783,7 @@ GLIBC_2.4 xprt_register F GLIBC_2.4 xprt_unregister F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist index 85e7746c10..f5f8c2d613 100644 --- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist +++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist @@ -2950,6 +2950,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist index 91dc1b8378..e505d338f4 100644 --- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist @@ -2836,3 +2836,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist index 3440e90f6f..c360b28fd1 100644 --- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist @@ -2833,3 +2833,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist index 5ee7b8c52f..fa09f9d9c9 100644 --- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist @@ -2911,6 +2911,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist index ae7474c0f0..1db4a115c8 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist @@ -2917,6 +2917,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist index cdf040dec2..770fa9b042 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist @@ -2819,6 +2819,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/or1k/libc.abilist b/sysdeps/unix/sysv/linux/or1k/libc.abilist index c356a11b1c..c41f91db28 100644 --- a/sysdeps/unix/sysv/linux/or1k/libc.abilist +++ b/sysdeps/unix/sysv/linux/or1k/libc.abilist @@ -2261,3 +2261,4 @@ GLIBC_2.40 setcontext F GLIBC_2.40 swapcontext F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist index 7937f94cf0..8eccaa5c92 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist @@ -3140,6 +3140,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist index d6e35f31d2..f827f65615 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist @@ -3185,6 +3185,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist index 2268d6890d..141186553d 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist @@ -2894,6 +2894,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist index 7f61b14bc8..7786c97072 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist @@ -2970,3 +2970,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist index 4187241f50..090a8a3cc3 100644 --- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist +++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist @@ -2514,3 +2514,4 @@ GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.40 __riscv_hwprobe F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist index 8935beccac..8f8daa10b2 100644 --- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist +++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist @@ -2714,3 +2714,4 @@ GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.40 __riscv_hwprobe F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist index e69dc7ccf6..68ad13d4d1 100644 --- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist +++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist @@ -3138,6 +3138,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist index 7d860001d8..b07e767d44 100644 --- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist +++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist @@ -2931,6 +2931,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist index fcb8161841..841da24118 100644 --- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist @@ -2830,6 +2830,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist index 3fd078d125..2a8cba719e 100644 --- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist @@ -2827,6 +2827,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist index 1ce1fe9da7..8f9031f344 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist @@ -3159,6 +3159,7 @@ GLIBC_2.4 wprintf F GLIBC_2.4 wscanf F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist index 07507b86f6..e5abc49fce 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist @@ -2795,6 +2795,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list index f1cfe8dc13..424bf43868 100644 --- a/sysdeps/unix/sysv/linux/syscalls.list +++ b/sysdeps/unix/sysv/linux/syscalls.list @@ -39,6 +39,7 @@ mlockall - mlockall i:i mlockall mount EXTRA mount i:sssUp __mount mount mount_setattr EXTRA mount_setattr i:isUpU mount_setattr move_mount EXTRA move_mount i:isisU move_mount +mseal EXTRA mseal i:bUU __mseal mseal munlock - munlock i:aU munlock munlockall - munlockall i: munlockall nfsservctl EXTRA nfsservctl i:ipp __compat_nfsservctl nfsservctl@GLIBC_2.0:GLIBC_2.28 diff --git a/sysdeps/unix/sysv/linux/tst-mseal-pkey.c b/sysdeps/unix/sysv/linux/tst-mseal-pkey.c new file mode 100644 index 0000000000..d194fbaaaf --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-mseal-pkey.c @@ -0,0 +1,84 @@ +/* Basic tests for mseal and pkey. + Copyright (C) 2025 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +static int +do_test (void) +{ + TEST_VERIFY_EXIT (mseal (MAP_FAILED, 0, 0) == -1); + if (errno == ENOSYS || errno == EPERM) + FAIL_UNSUPPORTED ("kernel does not support mseal"); + TEST_COMPARE (errno, EINVAL); + + int key = pkey_alloc (0, 0); + if (key < 0) + { + if (errno == ENOSYS) + FAIL_UNSUPPORTED + ("kernel does not support memory protection keys"); + if (errno == EINVAL) + FAIL_UNSUPPORTED + ("CPU does not support memory protection keys: %m"); + if (errno == ENOSPC) + FAIL_UNSUPPORTED + ("no keys available or kernel does not support memory" + " protection keys"); + FAIL_EXIT1 ("pkey_alloc: %m"); + } + + long pagesize = xsysconf (_SC_PAGESIZE); + + void *page = xmmap (NULL, pagesize, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1); + + TEST_COMPARE (pkey_mprotect (page, pagesize, PROT_READ | PROT_WRITE, + key), 0); + + TEST_VERIFY_EXIT (mseal (page, pagesize, 0) == 0); + + /* For certain destructive madvise behaviours (MADV_DONTNEED, + MADV_FREE, MADV_DONTNEED_LOCKED, and MADV_WIPEONFORK), mseal + only blocks the operation if the PKRU denies write. */ + TEST_VERIFY_EXIT (pkey_set (key, 0) == 0); + TEST_COMPARE (madvise (page, pagesize, MADV_DONTNEED), 0); + + /* The other mapping operation change are always blocked, + regardless of PKRU state. */ + TEST_COMPARE (pkey_mprotect (page, pagesize, PROT_READ, key), -1); + TEST_COMPARE (errno, EPERM); + + TEST_COMPARE (mprotect (page, pagesize, PROT_READ), -1); + TEST_COMPARE (errno, EPERM); + + TEST_VERIFY_EXIT (pkey_set (key, PKEY_DISABLE_WRITE) == 0); + TEST_COMPARE (madvise (page, pagesize, MADV_DONTNEED), -1); + TEST_COMPARE (errno, EPERM); + + TEST_COMPARE (mprotect (page, pagesize, PROT_READ), -1); + TEST_COMPARE (errno, EPERM); + TEST_COMPARE (munmap (page, pagesize),-1); + TEST_COMPARE (errno, EPERM); + + return 0; +} + +#include diff --git a/sysdeps/unix/sysv/linux/tst-mseal.c b/sysdeps/unix/sysv/linux/tst-mseal.c new file mode 100644 index 0000000000..0aff1e9e4c --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-mseal.c @@ -0,0 +1,67 @@ +/* Basic tests for mseal. + Copyright (C) 2025 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +static int +do_test (void) +{ + TEST_VERIFY_EXIT (mseal (MAP_FAILED, 0, 0) == -1); + if (errno == ENOSYS || errno == EPERM) + FAIL_UNSUPPORTED ("kernel does not support mseal"); + TEST_COMPARE (errno, EINVAL); + + size_t pagesize = getpagesize (); + void *p = xmmap (NULL, 4 * pagesize, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE, -1); + xmunmap (p + 2 * pagesize, pagesize); + + /* Unaligned address. */ + TEST_VERIFY_EXIT (mseal (p + 1, pagesize, 0) == -1); + TEST_COMPARE (errno, EINVAL); + + /* Length too big. */ + TEST_VERIFY_EXIT (mseal (p, 3 * pagesize, 0) == -1); + TEST_COMPARE (errno, ENOMEM); + + TEST_VERIFY_EXIT (mseal (p, pagesize, 0) == 0); + /* Apply the same seal should be idempotent. */ + TEST_VERIFY_EXIT (mseal (p, pagesize, 0) == 0); + + TEST_VERIFY_EXIT (mprotect (p, pagesize, PROT_WRITE) == -1); + TEST_COMPARE (errno, EPERM); + + TEST_VERIFY_EXIT (munmap (p, pagesize) == -1); + TEST_COMPARE (errno, EPERM); + + TEST_VERIFY_EXIT (mremap (p, pagesize, 2 * pagesize, 0) == MAP_FAILED); + TEST_COMPARE (errno, EPERM); + + TEST_VERIFY_EXIT (madvise (p, pagesize, MADV_DONTNEED) == -1); + TEST_COMPARE (errno, EPERM); + + xmunmap (p + pagesize, pagesize); + xmunmap (p + 3 * pagesize, pagesize); + + return 0; +} + +#include diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist index 5acf49dbe8..5a22654095 100644 --- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist +++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist @@ -2746,6 +2746,7 @@ GLIBC_2.4 unlinkat F GLIBC_2.4 unshare F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F GLIBC_2.5 __readlinkat_chk F GLIBC_2.5 inet6_opt_append F GLIBC_2.5 inet6_opt_find F diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist index 02d1bb97dc..d627f4fcce 100644 --- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist +++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist @@ -2765,3 +2765,4 @@ GLIBC_2.39 stdc_trailing_zeros_ull F GLIBC_2.39 stdc_trailing_zeros_us F GLIBC_2.41 sched_getattr F GLIBC_2.41 sched_setattr F +GLIBC_2.42 mseal F