From: Mark Brown <broonie@kernel.org> mainline inclusion from mainline-6.9 commit 4035c22ef7d43a6c00d6a6584c60e902b95b46af category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8904 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ---------------------------------------------------------------------- Add a new regset to expose FPMR via ptrace. It is not added to the FPSIMD registers since that structure is exposed elsewhere without any allowance for extension we don't add there. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-5-c568edc8ed7f@kernel... Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com> Signed-off-by: Hongye Lin <linhongye@h-partners.com> --- arch/arm64/kernel/ptrace.c | 42 ++++++++++++++++++++++++++++++++++++++ include/uapi/linux/elf.h | 1 + 2 files changed, 43 insertions(+) diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 6ddee2b5cf50..5543479f8c9c 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -696,6 +696,39 @@ static int tls_set(struct task_struct *target, const struct user_regset *regset, return ret; } +static int fpmr_get(struct task_struct *target, const struct user_regset *regset, + struct membuf to) +{ + if (!system_supports_fpmr()) + return -EINVAL; + + if (target == current) + fpsimd_preserve_current_state(); + + return membuf_store(&to, target->thread.uw.fpmr); +} + +static int fpmr_set(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + unsigned long fpmr; + + if (!system_supports_fpmr()) + return -EINVAL; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpmr, 0, count); + if (ret) + return ret; + + target->thread.uw.fpmr = fpmr; + + fpsimd_flush_task_state(target); + + return 0; +} + static int system_call_get(struct task_struct *target, const struct user_regset *regset, struct membuf to) @@ -1418,6 +1451,7 @@ enum aarch64_regset { REGSET_HW_BREAK, REGSET_HW_WATCH, #endif + REGSET_FPMR, REGSET_SYSTEM_CALL, #ifdef CONFIG_ARM64_SVE REGSET_SVE, @@ -1496,6 +1530,14 @@ static const struct user_regset aarch64_regsets[] = { .regset_get = system_call_get, .set = system_call_set, }, + [REGSET_FPMR] = { + .core_note_type = NT_ARM_FPMR, + .n = 1, + .size = sizeof(u64), + .align = sizeof(u64), + .regset_get = fpmr_get, + .set = fpmr_set, + }, #ifdef CONFIG_ARM64_SVE [REGSET_SVE] = { /* Scalable Vector Extension */ .core_note_type = NT_ARM_SVE, diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index 52a2ea81256e..5ae3c60826eb 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -440,6 +440,7 @@ typedef struct elf64_shdr { #define NT_ARM_SSVE 0x40b /* ARM Streaming SVE registers */ #define NT_ARM_ZA 0x40c /* ARM SME ZA registers */ #define NT_ARM_ZT 0x40d /* ARM SME ZT registers */ +#define NT_ARM_FPMR 0x40e /* ARM floating point mode register */ #define NT_ARC_V2 0x600 /* ARCv2 accumulator/extra registers */ #define NT_VMCOREDD 0x700 /* Vmcore Device Dump Note */ #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */ -- 2.33.0