[PATCH 10/17] delta: Fix buffer overrun in delta_ipc_open

From: Andi Kleen
Date: Thu Mar 21 2019 - 18:00:43 EST


From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

delta_ipc_open is always called with a single constant string
as name, but it uses a longer memcpy to copy the string to
a different structure. The memcpy would read outside the bounds
of the string, potentially accessing unmapped memory.

Just use strcpy instead after clearing the area.

This fixes a build error with LTO, which can detect this.

Cc: hugues.fruchet@xxxxxx
Cc: mchehab@xxxxxxxxxxxxxxxx
Fixes: 91c83f395fbe [media] st-delta: rpmsg ipc support
Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
---
drivers/media/platform/sti/delta/delta-ipc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/sti/delta/delta-ipc.c b/drivers/media/platform/sti/delta/delta-ipc.c
index a4603d573c34..bd1bbbeedec3 100644
--- a/drivers/media/platform/sti/delta/delta-ipc.c
+++ b/drivers/media/platform/sti/delta/delta-ipc.c
@@ -175,8 +175,8 @@ int delta_ipc_open(struct delta_ctx *pctx, const char *name,
msg.ipc_buf_size = ipc_buf_size;
msg.ipc_buf_paddr = ctx->ipc_buf->paddr;

- memcpy(msg.name, name, sizeof(msg.name));
- msg.name[sizeof(msg.name) - 1] = 0;
+ memset(msg.name, 0, sizeof(msg.name));
+ strcpy(msg.name, name);

msg.param_size = param->size;
memcpy(ctx->ipc_buf->vaddr, param->data, msg.param_size);
--
2.20.1