bianbu-linux-6.6/arch/x86
Kees Cook 2de5fd836b x86/syscall: Avoid memcpy() for ia32 syscall_get_arguments()
[ Upstream commit d19d638b1e6cf746263ef60b7d0dee0204d8216a ]

Modern (fortified) memcpy() prefers to avoid writing (or reading) beyond
the end of the addressed destination (or source) struct member:

In function ‘fortify_memcpy_chk’,
    inlined from ‘syscall_get_arguments’ at ./arch/x86/include/asm/syscall.h:85:2,
    inlined from ‘populate_seccomp_data’ at kernel/seccomp.c:258:2,
    inlined from ‘__seccomp_filter’ at kernel/seccomp.c:1231:3:
./include/linux/fortify-string.h:580:25: error: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Werror=attribute-warning]
  580 |                         __read_overflow2_field(q_size_field, size);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

As already done for x86_64 and compat mode, do not use memcpy() to
extract syscall arguments from struct pt_regs but rather just perform
direct assignments. Binary output differences are negligible, and actually
ends up using less stack space:

-       sub    $0x84,%esp
+       sub    $0x6c,%esp

and less text size:

   text    data     bss     dec     hex filename
  10794     252       0   11046    2b26 gcc-32b/kernel/seccomp.o.stock
  10714     252       0   10966    2ad6 gcc-32b/kernel/seccomp.o.after

Closes: https://lore.kernel.org/lkml/9b69fb14-df89-4677-9c82-056ea9e706f5@gmail.com/
Reported-by: Mirsad Todorovac <mtodorovac69@gmail.com>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Mirsad Todorovac <mtodorovac69@gmail.com>
Link: https://lore.kernel.org/all/20240708202202.work.477-kees%40kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-10 11:57:30 +02:00
..
boot x86/boot: Don't add the EFI stub to targets, again 2024-06-21 14:38:37 +02:00
coco x86/tdx: Fix "in-kernel MMIO" check 2024-10-04 16:30:05 +02:00
configs - The first, cleanup part of the microcode loader reorg tglx has been 2023-08-28 15:55:20 -07:00
crypto crypto: x86/sha256 - Add parentheses around macros' single arguments 2024-10-10 11:57:21 +02:00
entry x86/bhi: Avoid warning in #DB handler due to BHI mitigation 2024-07-18 13:21:27 +02:00
events perf/x86/intel/pt: Fix sampling synchronization 2024-10-04 16:29:52 +02:00
hyperv x86/hyperv: fix kexec crash due to VP assist page corruption 2024-09-18 19:24:07 +02:00
ia32
include x86/syscall: Avoid memcpy() for ia32 syscall_get_arguments() 2024-10-10 11:57:30 +02:00
kernel x86/kexec: Add EFI config table identity mapping for kexec kernel 2024-10-10 11:57:30 +02:00
kvm KVM: x86: Move x2APIC ICR helper above kvm_apic_write_nodecode() 2024-10-04 16:29:47 +02:00
lib x86/kmsan: Fix hook for unaligned accesses 2024-09-12 11:11:29 +02:00
math-emu x86/fpu: Include asm/fpu/regset.h 2023-05-18 11:56:18 -07:00
mm x86/mm: Use IPIs to synchronize LAM enablement 2024-10-04 16:29:04 +02:00
net Revert "bpf: Take return from set_memory_rox() into account with bpf_jit_binary_lock_ro()" 2024-07-09 11:44:29 +02:00
pci x86/PCI: Check pcie_find_root_port() return for NULL 2024-10-04 16:29:29 +02:00
platform x86/platform/iosf_mbi: Convert PCIBIOS_* return codes to errnos 2024-08-03 08:53:21 +02:00
power mm/treewide: replace pud_large() with pud_leaf() 2024-04-10 16:35:46 +02:00
purgatory x86/purgatory: Switch to the position-independent small code model 2024-06-12 11:11:43 +02:00
ras
realmode x86/realmode: Make stack lock work in trampoline_compat() 2023-05-30 14:11:47 +02:00
tools x86/boot: Ignore relocations in .notes sections in walk_relocs() too 2024-06-12 11:11:36 +02:00
um um: Fix the -Wmissing-prototypes warning for get_thread_reg 2024-06-12 11:12:42 +02:00
video Merge drm/drm-next into drm-misc-next 2023-07-24 15:44:47 +02:00
virt/vmx/tdx
xen xen: allow mapping ACPI data using a different physical address 2024-10-04 16:29:43 +02:00
.gitignore
Kbuild
Kconfig cpu: Ignore "mitigations" kernel parameter if CPU_MITIGATIONS=n 2024-06-12 11:11:24 +02:00
Kconfig.assembler x86/kconfig: Add as-instr64 macro to properly evaluate AS_WRUSS 2024-08-03 08:53:21 +02:00
Kconfig.cpu x86/Kconfig: Transmeta Crusoe is CPU family 5, not 6 2024-02-23 09:25:10 +01:00
Kconfig.debug x86/kconfig: Select ARCH_WANT_FRAME_POINTERS again when UNWINDER_FRAME_POINTER=y 2024-06-12 11:12:46 +02:00
Makefile kbuild: unify vdso_install rules 2024-06-12 11:12:32 +02:00
Makefile.postlink x86/build: Avoid relocation information in final vmlinux 2023-06-14 19:54:40 +02:00
Makefile.um um: Only disable SSE on clang to work around old GCC bugs 2023-04-04 09:57:05 +02:00
Makefile_32.cpu