strace/SOURCES/0166-tee-rewrite-num_params...

53 lines
1.8 KiB
Diff

From 3a68f90c2a5a208b475cc2014f85ae04541ec5b6 Mon Sep 17 00:00:00 2001
From: Eugene Syromyatnikov <evgsyr@gmail.com>
Date: Fri, 20 Aug 2021 21:31:01 +0200
Subject: [PATCH 150/150] tee: rewrite num_params access in tee_fetch_buf_data
Pointer to num_params field of the fetched structure is passed in a
separate function argument which provokes covscan complaints about
uninitialised accesses and also tingles my aliasing rules senses.
Rewrite to access it via the arg_struct argument which is fetched
earlier in the function flow.
* src/tee.c (TEE_FETCH_BUF_DATA): Change &arg_.num_params
to offsetof(typeof(arg_), num_params).
(tee_fetch_buf_data): Accept offset of the num_params field instead
of pointer to it; reconstruct the num_params pointer using it.
---
src/tee.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/src/tee.c b/src/tee.c
index f9eda52..d7e9b15 100644
--- a/src/tee.c
+++ b/src/tee.c
@@ -33,7 +33,7 @@ struct tee_ioctl_shm_register_fd_data {
#define TEE_FETCH_BUF_DATA(buf_, arg_, params_) \
tee_fetch_buf_data(tcp, arg, &buf_, sizeof(arg_), \
- &arg_, &arg_.num_params, \
+ &arg_, offsetof(typeof(arg_), num_params), \
params_)
/* session id is printed as 0x%x in libteec */
@@ -56,7 +56,7 @@ tee_fetch_buf_data(struct tcb *const tcp,
struct tee_ioctl_buf_data *buf,
size_t arg_size,
void *arg_struct,
- unsigned *num_params,
+ size_t num_params_offs,
uint64_t *params)
{
if (umove_or_printaddr(tcp, arg, buf))
@@ -69,6 +69,7 @@ tee_fetch_buf_data(struct tcb *const tcp,
tee_print_buf(buf);
return RVAL_IOCTL_DECODED;
}
+ uint32_t *num_params = (uint32_t *) (arg_struct + num_params_offs);
if (entering(tcp) &&
(arg_size + TEE_IOCTL_PARAM_SIZE(*num_params) != buf->buf_len)) {
/*
--
2.1.4