From: Dan Carpenter <dan.carpenter@oracle.com> stable inclusion from stable-5.10.50 commit f93737061067f95af5e8058793e8bcac95473588 bugzilla: 174522 https://gitee.com/openeuler/kernel/issues/I4DNFY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 4a36e160856db8a8ddd6a3d2e5db5a850ab87f82 ] There needs to be a check to verify that we don't read beyond the end of "buf". This function is called from do_rx(). The "buf" is the USB transfer_buffer and "len" is "urb->actual_length". Fixes: 61e121047645 ("staging: gdm7240: adding LTE USB driver") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/YMcnl4zCwGWGDVMG@mwanda Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/staging/gdm724x/gdm_lte.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/staging/gdm724x/gdm_lte.c b/drivers/staging/gdm724x/gdm_lte.c index 571f47d39484..a41af7aa74ec 100644 --- a/drivers/staging/gdm724x/gdm_lte.c +++ b/drivers/staging/gdm724x/gdm_lte.c @@ -677,6 +677,7 @@ static void gdm_lte_multi_sdu_pkt(struct phy_dev *phy_dev, char *buf, int len) struct sdu *sdu = NULL; u8 endian = phy_dev->get_endian(phy_dev->priv_dev); u8 *data = (u8 *)multi_sdu->data; + int copied; u16 i = 0; u16 num_packet; u16 hci_len; @@ -688,6 +689,12 @@ static void gdm_lte_multi_sdu_pkt(struct phy_dev *phy_dev, char *buf, int len) num_packet = gdm_dev16_to_cpu(endian, multi_sdu->num_packet); for (i = 0; i < num_packet; i++) { + copied = data - multi_sdu->data; + if (len < copied + sizeof(*sdu)) { + pr_err("rx prevent buffer overflow"); + return; + } + sdu = (struct sdu *)data; cmd_evt = gdm_dev16_to_cpu(endian, sdu->cmd_evt); @@ -698,7 +705,8 @@ static void gdm_lte_multi_sdu_pkt(struct phy_dev *phy_dev, char *buf, int len) pr_err("rx sdu wrong hci %04x\n", cmd_evt); return; } - if (hci_len < 12) { + if (hci_len < 12 || + len < copied + sizeof(*sdu) + (hci_len - 12)) { pr_err("rx sdu invalid len %d\n", hci_len); return; } -- 2.20.1