Commit-ID: aee4b013a71666f11ffeac11ab45bb7c6e0e394d Gitweb: http://git.kernel.org/tip/aee4b013a71666f11ffeac11ab45bb7c6e0e394d Author: Denys Vlasenko <[email protected]> AuthorDate: Tue, 9 Jun 2015 20:54:07 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 10 Jun 2015 08:42:12 +0200
x86/asm/entry/32: Fix fallout from the R9 trick removal in the SYSCALL code I put %ebp restoration code too late. Under strace, it is not reached and %ebp is not restored upon return to userspace. This is the fix. Run-tested. 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 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 2093ce6..2c44180 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -344,6 +344,7 @@ cstar_dispatch: call *ia32_sys_call_table(, %rax, 8) movq %rax, RAX(%rsp) 1: + movl RCX(%rsp), %ebp DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF testl $_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS) @@ -351,7 +352,6 @@ cstar_dispatch: sysretl_from_sys_call: andl $~TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS) - movl RCX(%rsp), %ebp RESTORE_RSI_RDI_RDX movl RIP(%rsp), %ecx movl EFLAGS(%rsp), %r11d -- 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/
