6.1-stable review patch. If anyone has any objections, please let me know.
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From: Maurizio Lombardi mlombard@redhat.com
[ Upstream commit efa56305908ba20de2104f1b8508c6a7401833be ]
If the host sends an H2CData command with an invalid DATAL, the kernel may crash in nvmet_tcp_build_pdu_iovec().
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 lr : nvmet_tcp_io_work+0x6ac/0x718 [nvmet_tcp] Call trace: process_one_work+0x174/0x3c8 worker_thread+0x2d0/0x3e8 kthread+0x104/0x110
Fix the bug by raising a fatal error if DATAL isn't coherent with the packet size. Also, the PDU length should never exceed the MAXH2CDATA parameter which has been communicated to the host in nvmet_tcp_handle_icreq().
Fixes: 872d26a391da ("nvmet-tcp: add NVMe over TCP target driver") Signed-off-by: Maurizio Lombardi mlombard@redhat.com Reviewed-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/target/tcp.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index 355d80323b83..7310f65af849 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -18,6 +18,7 @@ #include "nvmet.h"
#define NVMET_TCP_DEF_INLINE_DATA_SIZE (4 * PAGE_SIZE) +#define NVMET_TCP_MAXH2CDATA 0x400000 /* 16M arbitrary limit */
/* Define the socket priority to use for connections were it is desirable * that the NIC consider performing optimized packet processing or filtering. @@ -861,7 +862,7 @@ static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) icresp->hdr.pdo = 0; icresp->hdr.plen = cpu_to_le32(icresp->hdr.hlen); icresp->pfv = cpu_to_le16(NVME_TCP_PFV_1_0); - icresp->maxdata = cpu_to_le32(0x400000); /* 16M arbitrary limit */ + icresp->maxdata = cpu_to_le32(NVMET_TCP_MAXH2CDATA); icresp->cpda = 0; if (queue->hdr_digest) icresp->digest |= NVME_TCP_HDR_DIGEST_ENABLE; @@ -914,6 +915,7 @@ static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) { struct nvme_tcp_data_pdu *data = &queue->pdu.data; struct nvmet_tcp_cmd *cmd; + unsigned int plen;
if (likely(queue->nr_cmds)) { if (unlikely(data->ttag >= queue->nr_cmds)) { @@ -937,7 +939,16 @@ static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) return -EPROTO; }
+ plen = le32_to_cpu(data->hdr.plen); cmd->pdu_len = le32_to_cpu(data->data_length); + if (unlikely(cmd->pdu_len != (plen - sizeof(*data)) || + cmd->pdu_len == 0 || + cmd->pdu_len > NVMET_TCP_MAXH2CDATA)) { + pr_err("H2CData PDU len %u is invalid\n", cmd->pdu_len); + /* FIXME: use proper transport errors */ + nvmet_tcp_fatal_error(queue); + return -EPROTO; + } cmd->pdu_recv = 0; nvmet_tcp_build_pdu_iovec(cmd); queue->cmd = cmd;