On Wed, May 03, 2017 at 02:48:28PM +0200, Andrey Konovalov wrote:
> Hi,
>
> I've got the following error report while fuzzing the kernel with syzkaller.
>
> On commit 89c9fea3c8034cdb2fd745f551cde0b507fd6893 (4.11.0+).
>
> A reproducer and .config are attached.
>
> The reproducer open SCTP sockets and sends data to it in a loop.
> I'm not sure whether this is an issue with SCTP or with something else.
>
> WARNING: kernel stack regs at ffff8800686869f8 in a.out:4933 has bad
> 'bp' value c3fc855a10167ec0
Hi Andrey,
Can you test this patch?
diff --git a/arch/x86/lib/csum-copy_64.S b/arch/x86/lib/csum-copy_64.S
index 7e48807..45a53df 100644
--- a/arch/x86/lib/csum-copy_64.S
+++ b/arch/x86/lib/csum-copy_64.S
@@ -55,7 +55,7 @@ ENTRY(csum_partial_copy_generic)
movq %r12, 3*8(%rsp)
movq %r14, 4*8(%rsp)
movq %r13, 5*8(%rsp)
- movq %rbp, 6*8(%rsp)
+ movq %r15, 6*8(%rsp)
movq %r8, (%rsp)
movq %r9, 1*8(%rsp)
@@ -74,7 +74,7 @@ ENTRY(csum_partial_copy_generic)
/* main loop. clear in 64 byte blocks */
/* r9: zero, r8: temp2, rbx: temp1, rax: sum, rcx: saved length */
/* r11: temp3, rdx: temp4, r12 loopcnt */
- /* r10: temp5, rbp: temp6, r14 temp7, r13 temp8 */
+ /* r10: temp5, r15: temp6, r14 temp7, r13 temp8 */
.p2align 4
.Lloop:
source
@@ -89,7 +89,7 @@ ENTRY(csum_partial_copy_generic)
source
movq 32(%rdi), %r10
source
- movq 40(%rdi), %rbp
+ movq 40(%rdi), %r15
source
movq 48(%rdi), %r14
source
@@ -103,7 +103,7 @@ ENTRY(csum_partial_copy_generic)
adcq %r11, %rax
adcq %rdx, %rax
adcq %r10, %rax
- adcq %rbp, %rax
+ adcq %r15, %rax
adcq %r14, %rax
adcq %r13, %rax
@@ -121,7 +121,7 @@ ENTRY(csum_partial_copy_generic)
dest
movq %r10, 32(%rsi)
dest
- movq %rbp, 40(%rsi)
+ movq %r15, 40(%rsi)
dest
movq %r14, 48(%rsi)
dest
@@ -203,7 +203,7 @@ ENTRY(csum_partial_copy_generic)
movq 3*8(%rsp), %r12
movq 4*8(%rsp), %r14
movq 5*8(%rsp), %r13
- movq 6*8(%rsp), %rbp
+ movq 6*8(%rsp), %r15
addq $7*8, %rsp
ret
