Commit-ID: eb47854415825a69b1c578e7487da571227ba25a Gitweb: http://git.kernel.org/tip/eb47854415825a69b1c578e7487da571227ba25a Author: Denys Vlasenko <[email protected]> AuthorDate: Sun, 7 Jun 2015 20:24:30 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Mon, 8 Jun 2015 23:43:37 +0200
x86/asm/entry/32: Reinstate clearing of pt_regs->r8..r11 on EFAULT path I broke this recently when I changed pt_regs->r8..r11 clearing logic in INT 80 code path. There is a branch from SYSENTER/SYSCALL code to INT 80 code: if we fail to retrieve arg6, we return EFAULT. Before this patch, in this case we don't clear pt_regs->r8..r11. This patch fixes this. The resulting code is smaller and simpler. While at it, remove incorrect comment about syscall dispatching CALL insn: it does not use RIP-relative addressing form (the comment was meant to be "TODO: make this rip-relative", and morphed since then, dropping "TODO"). Signed-off-by: Denys Vlasenko <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Kees Cook <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Drewry <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/entry/entry_64_compat.S | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 59840e3..5757dde 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -413,9 +413,7 @@ END(entry_SYSCALL_compat) ia32_badarg: ASM_CLAC - movq $-EFAULT, %rax - jmp ia32_sysret - + movq $-EFAULT, RAX(%rsp) ia32_ret_from_sys_call: xorl %eax, %eax /* Do not leak kernel information */ movq %rax, R11(%rsp) @@ -486,9 +484,7 @@ ia32_do_call: cmpq $(IA32_NR_syscalls-1), %rax ja 1f - call *ia32_sys_call_table(, %rax, 8) /* RIP relative */ - -ia32_sysret: + call *ia32_sys_call_table(, %rax, 8) movq %rax, RAX(%rsp) 1: jmp int_ret_from_sys_call -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
