Re: [PATCH] net: bnx2x: fix variable dereferenced before check
flat view
From: Johan Hovold <johan@kernel.org>
Date: 2021-11-18 08:53:00
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[ Adding Dan. ] On Sun, Nov 14, 2021 at 01:36:36AM +0300, Pavel Skripkin wrote:
Smatch says: bnx2x_init_ops.h:640 bnx2x_ilt_client_mem_op() warn: variable dereferenced before check 'ilt' (see line 638) Move ilt_cli variable initialization _after_ ilt validation, because it's unsafe to deref the pointer before validation check.
It seems smatch is confused here. There is no dereference happening until after the check, we're just determining the address when initialising ilt_cli. I know this has been applied, and the change itself is fine, but the patch description is wrong and the Fixes tag is unwarranted.
quoted hunk ↗ jump to hunk
Fixes: 523224a3b3cd ("bnx2x, cnic, bnx2i: use new FW/HSI") Signed-off-by: Pavel Skripkin <redacted> --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_init_ops.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_init_ops.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_init_ops.h index 1835d2e451c0..fc7fce642666 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_init_ops.h +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_init_ops.h@@ -635,11 +635,13 @@ static int bnx2x_ilt_client_mem_op(struct bnx2x *bp, int cli_num, { int i, rc; struct bnx2x_ilt *ilt = BP_ILT(bp); - struct ilt_client_info *ilt_cli = &ilt->clients[cli_num]; + struct ilt_client_info *ilt_cli; if (!ilt || !ilt->lines) return -1; + ilt_cli = &ilt->clients[cli_num]; + if (ilt_cli->flags & (ILT_CLIENT_SKIP_INIT | ILT_CLIENT_SKIP_MEM)) return 0;
Johan