diff options
| author | Lai Jiangshan <jiangshan.ljs@antgroup.com> | 2022-04-12 15:49:08 +0300 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-05-19 11:56:46 +0300 |
| commit | 47f33de4aafb2f5e43d480d590a939d0f1d566a9 (patch) | |
| tree | c6b66cbc91c6b6438bac5fb53b9f0ff98af1ad18 /arch/x86/include/asm/ptrace.h | |
| parent | c42b145181aafd59ed31ccd879493389e3ea5a08 (diff) | |
| download | linux-47f33de4aafb2f5e43d480d590a939d0f1d566a9.tar.xz | |
x86/sev: Mark the code returning to user space as syscall gap
When returning to user space, %rsp is user-controlled value.
If it is a SNP-guest and the hypervisor decides to mess with the
code-page for this path while a CPU is executing it, a potential #VC
could hit in the syscall return path and mislead the #VC handler.
So make ip_within_syscall_gap() return true in this case.
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20220412124909.10467-1-jiangshanlai@gmail.com
Diffstat (limited to 'arch/x86/include/asm/ptrace.h')
| -rw-r--r-- | arch/x86/include/asm/ptrace.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 4357e0f2cd5f..f4db78b09c8f 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -186,9 +186,13 @@ static __always_inline bool ip_within_syscall_gap(struct pt_regs *regs) bool ret = (regs->ip >= (unsigned long)entry_SYSCALL_64 && regs->ip < (unsigned long)entry_SYSCALL_64_safe_stack); + ret = ret || (regs->ip >= (unsigned long)entry_SYSRETQ_unsafe_stack && + regs->ip < (unsigned long)entry_SYSRETQ_end); #ifdef CONFIG_IA32_EMULATION ret = ret || (regs->ip >= (unsigned long)entry_SYSCALL_compat && regs->ip < (unsigned long)entry_SYSCALL_compat_safe_stack); + ret = ret || (regs->ip >= (unsigned long)entry_SYSRETL_compat_unsafe_stack && + regs->ip < (unsigned long)entry_SYSRETL_compat_end); #endif return ret; |