diff mbox series

fix stack missing after sp is updated

Message ID 20210104105451.6408-1-wangshuo47@huawei.com
State Committed
Commit cd6274089f7a7603cdaf2a24cef575fa61d3772e
Headers
Series fix stack missing after sp is updated |

Commit Message

Shuo Wang Jan. 4, 2021, 10:54 a.m. UTC 
  After sp is updated, the CFA offset should be set before next instruction.
Tested in glibc-2.28
Before fixing:
Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
149		stp	x1,  x2, [sp, #-32]!
Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
150		stp	x3,  x4, [sp, #16]
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
157		mrs	x4, tpidr_el0
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78

After fixing:
Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
149		stp	x1,  x2, [sp, #-32]!
Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf567aac in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
(gdb) ni
151		stp	x3,  x4, [sp, #16]
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:151
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf567aac in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
(gdb) ni
157		mrs	x4, tpidr_el0
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf567aac in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78

Signed-off-by: liqingqing <liqingqing3@huawei.com>
Signed-off-by: Shuo Wang <wangshuo47@huawei.com>
---
 sysdeps/aarch64/dl-tlsdesc.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Szabolcs Nagy Jan. 4, 2021, 12:34 p.m. UTC | #1 
The 01/04/2021 18:54, Shuo Wang wrote:
> After sp is updated, the CFA offset should be set before next instruction.
> Tested in glibc-2.28
> Before fixing:
> Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
> 149		stp	x1,  x2, [sp, #-32]!
> Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
> (gdb) bt
> #0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
> #1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
>     at /home/test/test_function.c:30
> #2  0x0000000000400c08 in initaaa () at thread.c:58
> #3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
> #4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
> #5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
> (gdb) ni
> _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
> 150		stp	x3,  x4, [sp, #16]
> (gdb) bt
> #0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
> #1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
>     at /home/test/test_function.c:30
> #2  0x0000000000000000 in ?? ()
> Backtrace stopped: previous frame identical to this frame (corrupt stack?)
> (gdb) ni
> _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
> 157		mrs	x4, tpidr_el0
> (gdb) bt
> #0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
> #1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
>     at /home/test/test_function.c:30
> #2  0x0000000000400c08 in initaaa () at thread.c:58
> #3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
> #4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
> #5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
> 
> After fixing:
> Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
> 149		stp	x1,  x2, [sp, #-32]!
> Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
> (gdb) bt
> #0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
> #1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
>     at /home/test/test_function.c:30
> #2  0x0000000000400c08 in initaaa () at thread.c:58
> #3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
> #4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
> #5  0x0000ffffbf567aac in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
> (gdb) ni
> 151		stp	x3,  x4, [sp, #16]
> (gdb) bt
> #0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:151
> #1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
>     at /home/test/test_function.c:30
> #2  0x0000000000400c08 in initaaa () at thread.c:58
> #3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
> #4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
> #5  0x0000ffffbf567aac in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
> (gdb) ni
> 157		mrs	x4, tpidr_el0
> (gdb) bt
> #0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
> #1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
>     at /home/test/test_function.c:30
> #2  0x0000000000400c08 in initaaa () at thread.c:58
> #3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
> #4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
> #5  0x0000ffffbf567aac in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
> 
> Signed-off-by: liqingqing <liqingqing3@huawei.com>
> Signed-off-by: Shuo Wang <wangshuo47@huawei.com>

please add 'aarch64: ' prefix to the subject.

i think it's enough to have the before the fix gdb
session in the commit message.

with those changes this is ok to commit.
(if you don't have commit rights then send
an updated patch and i'll commit it for you)

> ---
>  sysdeps/aarch64/dl-tlsdesc.S | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sysdeps/aarch64/dl-tlsdesc.S b/sysdeps/aarch64/dl-tlsdesc.S
> index 0046d29f9b..425e45a50f 100644
> --- a/sysdeps/aarch64/dl-tlsdesc.S
> +++ b/sysdeps/aarch64/dl-tlsdesc.S
> @@ -150,8 +150,8 @@ _dl_tlsdesc_dynamic:
>  	/* Save just enough registers to support fast path, if we fall
>  	   into slow path we will save additional registers.  */
>  	stp	x1,  x2, [sp, #-32]!
> -	stp	x3,  x4, [sp, #16]
>  	cfi_adjust_cfa_offset (32)
> +	stp	x3,  x4, [sp, #16]
>  	cfi_rel_offset (x1, 0)
>  	cfi_rel_offset (x2, 8)
>  	cfi_rel_offset (x3, 16)
> -- 
> 2.23.0
>
diff mbox series

Patch

diff --git a/sysdeps/aarch64/dl-tlsdesc.S b/sysdeps/aarch64/dl-tlsdesc.S
index 0046d29f9b..425e45a50f 100644
--- a/sysdeps/aarch64/dl-tlsdesc.S
+++ b/sysdeps/aarch64/dl-tlsdesc.S
@@ -150,8 +150,8 @@  _dl_tlsdesc_dynamic:
 	/* Save just enough registers to support fast path, if we fall
 	   into slow path we will save additional registers.  */
 	stp	x1,  x2, [sp, #-32]!
-	stp	x3,  x4, [sp, #16]
 	cfi_adjust_cfa_offset (32)
+	stp	x3,  x4, [sp, #16]
 	cfi_rel_offset (x1, 0)
 	cfi_rel_offset (x2, 8)
 	cfi_rel_offset (x3, 16)