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-rw-r--r--patches/source/linux-2.6.33.4/kernel.CVE-2010-3301.a.diff97
1 files changed, 97 insertions, 0 deletions
diff --git a/patches/source/linux-2.6.33.4/kernel.CVE-2010-3301.a.diff b/patches/source/linux-2.6.33.4/kernel.CVE-2010-3301.a.diff
new file mode 100644
index 00000000..8506e331
--- /dev/null
+++ b/patches/source/linux-2.6.33.4/kernel.CVE-2010-3301.a.diff
@@ -0,0 +1,97 @@
+From 36d001c70d8a0144ac1d038f6876c484849a74de Mon Sep 17 00:00:00 2001
+From: H. Peter Anvin <hpa@linux.intel.com>
+Date: Tue, 14 Sep 2010 12:42:41 -0700
+Subject: [PATCH] x86-64, compat: Test %rax for the syscall number, not %eax
+
+On 64 bits, we always, by necessity, jump through the system call
+table via %rax. For 32-bit system calls, in theory the system call
+number is stored in %eax, and the code was testing %eax for a valid
+system call number. At one point we loaded the stored value back from
+the stack to enforce zero-extension, but that was removed in checkin
+d4d67150165df8bf1cc05e532f6efca96f907cab. An actual 32-bit process
+will not be able to introduce a non-zero-extended number, but it can
+happen via ptrace.
+
+Instead of re-introducing the zero-extension, test what we are
+actually going to use, i.e. %rax. This only adds a handful of REX
+prefixes to the code.
+
+Reported-by: Ben Hawkes <hawkes@sota.gen.nz>
+Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
+Cc: <stable@kernel.org>
+Cc: Roland McGrath <roland@redhat.com>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+---
+ arch/x86/ia32/ia32entry.S | 14 +++++++-------
+ 1 files changed, 7 insertions(+), 7 deletions(-)
+
+diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
+index b86feab..84e3a4e 100644
+--- a/arch/x86/ia32/ia32entry.S
++++ b/arch/x86/ia32/ia32entry.S
+@@ -153,7 +153,7 @@ ENTRY(ia32_sysenter_target)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10)
+ CFI_REMEMBER_STATE
+ jnz sysenter_tracesys
+- cmpl $(IA32_NR_syscalls-1),%eax
++ cmpq $(IA32_NR_syscalls-1),%rax
+ ja ia32_badsys
+ sysenter_do_call:
+ IA32_ARG_FIXUP
+@@ -195,7 +195,7 @@ sysexit_from_sys_call:
+ movl $AUDIT_ARCH_I386,%edi /* 1st arg: audit arch */
+ call audit_syscall_entry
+ movl RAX-ARGOFFSET(%rsp),%eax /* reload syscall number */
+- cmpl $(IA32_NR_syscalls-1),%eax
++ cmpq $(IA32_NR_syscalls-1),%rax
+ ja ia32_badsys
+ movl %ebx,%edi /* reload 1st syscall arg */
+ movl RCX-ARGOFFSET(%rsp),%esi /* reload 2nd syscall arg */
+@@ -248,7 +248,7 @@ sysenter_tracesys:
+ call syscall_trace_enter
+ LOAD_ARGS32 ARGOFFSET /* reload args from stack in case ptrace changed it */
+ RESTORE_REST
+- cmpl $(IA32_NR_syscalls-1),%eax
++ cmpq $(IA32_NR_syscalls-1),%rax
+ ja int_ret_from_sys_call /* sysenter_tracesys has set RAX(%rsp) */
+ jmp sysenter_do_call
+ CFI_ENDPROC
+@@ -314,7 +314,7 @@ ENTRY(ia32_cstar_target)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10)
+ CFI_REMEMBER_STATE
+ jnz cstar_tracesys
+- cmpl $IA32_NR_syscalls-1,%eax
++ cmpq $IA32_NR_syscalls-1,%rax
+ ja ia32_badsys
+ cstar_do_call:
+ IA32_ARG_FIXUP 1
+@@ -367,7 +367,7 @@ cstar_tracesys:
+ LOAD_ARGS32 ARGOFFSET, 1 /* reload args from stack in case ptrace changed it */
+ RESTORE_REST
+ xchgl %ebp,%r9d
+- cmpl $(IA32_NR_syscalls-1),%eax
++ cmpq $(IA32_NR_syscalls-1),%rax
+ ja int_ret_from_sys_call /* cstar_tracesys has set RAX(%rsp) */
+ jmp cstar_do_call
+ END(ia32_cstar_target)
+@@ -425,7 +425,7 @@ ENTRY(ia32_syscall)
+ orl $TS_COMPAT,TI_status(%r10)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10)
+ jnz ia32_tracesys
+- cmpl $(IA32_NR_syscalls-1),%eax
++ cmpq $(IA32_NR_syscalls-1),%rax
+ ja ia32_badsys
+ ia32_do_call:
+ IA32_ARG_FIXUP
+@@ -444,7 +444,7 @@ ia32_tracesys:
+ call syscall_trace_enter
+ LOAD_ARGS32 ARGOFFSET /* reload args from stack in case ptrace changed it */
+ RESTORE_REST
+- cmpl $(IA32_NR_syscalls-1),%eax
++ cmpq $(IA32_NR_syscalls-1),%rax
+ ja int_ret_from_sys_call /* ia32_tracesys has set RAX(%rsp) */
+ jmp ia32_do_call
+ END(ia32_syscall)
+--
+1.7.3
+