| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Fri, 24 Jul 2015 07:19:20 -0700 From: tip-bot for Denys Vlasenko <tipbot@...or.com> To: linux-tip-commits@...r.kernel.org Cc: rostedt@...dmis.org, wad@...omium.org, mingo@...nel.org, torvalds@...ux-foundation.org, ast@...mgrid.com, sobkas@...il.com, luto@...capital.net, keescook@...omium.org, bp@...en8.de, oleg@...hat.com, fweisbec@...il.com, tglx@...utronix.de, linux-kernel@...r.kernel.org, hpa@...or.com, dvlasenk@...hat.com Subject: [tip:x86/urgent] x86/asm/entry/32: Revert ' Do not use R9 in SYSCALL32' commit Commit-ID: b1e194de6c8df2e5df8a8a1c1678cc2025439857 Gitweb: http://git.kernel.org/tip/b1e194de6c8df2e5df8a8a1c1678cc2025439857 Author: Denys Vlasenko <dvlasenk@...hat.com> AuthorDate: Fri, 24 Jul 2015 14:16:43 +0200 Committer: Thomas Gleixner <tglx@...utronix.de> CommitDate: Fri, 24 Jul 2015 16:16:55 +0200 x86/asm/entry/32: Revert 'Do not use R9 in SYSCALL32' commit This change reverts most of commit 53e9accf0f 'Do not use R9 in SYSCALL32'. I don't yet understand how, but code in that commit sometimes fails to preserve EBP. See https://bugzilla.kernel.org/show_bug.cgi?id=101061 "Problems while executing 32-bit code on AMD64" Reported-and-tested-by: Krzysztof A. Sobiecki <sobkas@...il.com> Signed-off-by: Denys Vlasenko <dvlasenk@...hat.com> Cc: Linus Torvalds <torvalds@...ux-foundation.org> Cc: Steven Rostedt <rostedt@...dmis.org> Cc: Borislav Petkov <bp@...en8.de> Cc: Andy Lutomirski <luto@...capital.net> Cc: Oleg Nesterov <oleg@...hat.com> Cc: Frederic Weisbecker <fweisbec@...il.com> Cc: Alexei Starovoitov <ast@...mgrid.com> Cc: Will Drewry <wad@...omium.org> Cc: Kees Cook <keescook@...omium.org> CC: x86@...nel.org Link: http://lkml.kernel.org/r/1437740203-11552-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Thomas Gleixner <tglx@...utronix.de> --- arch/x86/entry/entry_64_compat.S | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index bb187a6..5a18447 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -205,7 +205,6 @@ sysexit_from_sys_call: movl RDX(%rsp), %edx /* arg3 */ movl RSI(%rsp), %ecx /* arg4 */ movl RDI(%rsp), %r8d /* arg5 */ - movl %ebp, %r9d /* arg6 */ .endm .macro auditsys_exit exit @@ -236,6 +235,7 @@ sysexit_from_sys_call: sysenter_auditsys: auditsys_entry_common + movl %ebp, %r9d /* reload 6th syscall arg */ jmp sysenter_dispatch sysexit_audit: @@ -336,7 +336,7 @@ ENTRY(entry_SYSCALL_compat) * 32-bit zero extended: */ ASM_STAC -1: movl (%r8), %ebp +1: movl (%r8), %r9d _ASM_EXTABLE(1b, ia32_badarg) ASM_CLAC orl $TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS) @@ -346,7 +346,7 @@ ENTRY(entry_SYSCALL_compat) cstar_do_call: /* 32-bit syscall -> 64-bit C ABI argument conversion */ movl %edi, %r8d /* arg5 */ - movl %ebp, %r9d /* arg6 */ + /* r9 already loaded */ /* arg6 */ xchg %ecx, %esi /* rsi:arg2, rcx:arg4 */ movl %ebx, %edi /* arg1 */ movl %edx, %edx /* arg3 (zero extension) */ @@ -358,7 +358,6 @@ 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) @@ -392,7 +391,9 @@ sysretl_from_sys_call: #ifdef CONFIG_AUDITSYSCALL cstar_auditsys: + movl %r9d, R9(%rsp) /* register to be clobbered by call */ auditsys_entry_common + movl R9(%rsp), %r9d /* reload 6th syscall arg */ jmp cstar_dispatch sysretl_audit: @@ -404,14 +405,16 @@ cstar_tracesys: testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS) jz cstar_auditsys #endif + xchgl %r9d, %ebp SAVE_EXTRA_REGS xorl %eax, %eax /* Do not leak kernel information */ movq %rax, R11(%rsp) movq %rax, R10(%rsp) - movq %rax, R9(%rsp) + movq %r9, R9(%rsp) movq %rax, R8(%rsp) movq %rsp, %rdi /* &pt_regs -> arg1 */ call syscall_trace_enter + movl R9(%rsp), %r9d /* Reload arg registers from stack. (see sysenter_tracesys) */ movl RCX(%rsp), %ecx @@ -421,6 +424,7 @@ cstar_tracesys: movl %eax, %eax /* zero extension */ RESTORE_EXTRA_REGS + xchgl %ebp, %r9d jmp cstar_do_call END(entry_SYSCALL_compat) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists