xtensa: fix KASAN report for show_stack

commit 1d3b7a788c upstream.

show_stack dumps raw stack contents which may trigger an unnecessary
KASAN report. Fix it by copying stack contents to a temporary buffer
with __memcpy and then printing that buffer instead of passing stack
pointer directly to the print_hex_dump.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Max Filippov 2023-03-16 23:00:21 -07:00 committed by Greg Kroah-Hartman
parent 8ada1b5c8b
commit 08bfd05987

View file

@ -503,7 +503,7 @@ static size_t kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
{
size_t len;
size_t len, off = 0;
if (!sp)
sp = stack_pointer(task);
@ -512,9 +512,17 @@ void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
kstack_depth_to_print * STACK_DUMP_ENTRY_SIZE);
printk("%sStack:\n", loglvl);
print_hex_dump(loglvl, " ", DUMP_PREFIX_NONE,
STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE,
sp, len, false);
while (off < len) {
u8 line[STACK_DUMP_LINE_SIZE];
size_t line_len = len - off > STACK_DUMP_LINE_SIZE ?
STACK_DUMP_LINE_SIZE : len - off;
__memcpy(line, (u8 *)sp + off, line_len);
print_hex_dump(loglvl, " ", DUMP_PREFIX_NONE,
STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE,
line, line_len, false);
off += STACK_DUMP_LINE_SIZE;
}
show_trace(task, sp, loglvl);
}