From e3e7a85730a4b17efa1e2ff4088443c4753be683 Mon Sep 17 00:00:00 2001 From: Yingjie Wang <1075151112@qq.com> Date: Wed, 28 Oct 2026 19:57:19 +0800 Subject: [PATCH] nvmet-tcp: validate the TLS handshake timeout tls_handshake_timeout is writable but stored as a signed int. Multiplying the value by MSEC_PER_SEC and HZ therefore uses signed arithmetic. With HZ=1000, setting it to 2147484 overflows both multiplications. If the handshake request is accepted and remains pending, the timer wheel treats the jiffies delay as already expired and queues the timeout work on its next advance, while the handshake agent was given about 24.9 days. Negative values such as -1 cause the same immediate kernel-side timeout. Store the parameter as an unsigned int and reject values that cannot be represented both by tls_handshake_args::ta_timeout_ms and by a safe jiffies delay. Take one snapshot so a concurrent parameter update cannot give the handshake agent and delayed work different timeouts. Document the accepted range for built-in use. Negative and oversized values now fail with -EINVAL. Keep zero valid, preserving the existing immediate-timeout behavior. Fixes: 675b453e0241 ("nvmet-tcp: enable TLS handshake upcall") Cc: stable@vger.kernel.org Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Signed-off-by: Yingjie Wang <1075151112@qq.com> Signed-off-by: Keith Busch --- .../admin-guide/kernel-parameters.txt | 5 ++++ drivers/nvme/target/tcp.c | 26 ++++++++++++++++--- 2 files changed, 27 insertions(+), 4 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 68647ff4bdd2..5bd8a24be6b6 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4801,6 +4801,11 @@ Kernel parameters Example: nvme.quirks=7710:2267:bogus_nid,^identify_cns-9900:7711:broken_msi + nvmet_tcp.tls_handshake_timeout= + [NVME] NVMe/TCP target TLS handshake timeout in seconds. + Valid values range from 0 to the smaller of + UINT_MAX / 1000 and MAX_JIFFY_OFFSET / HZ. Default: 10 + ohci1394_dma=early [HW,EARLY] enable debugging via the ohci1394 driver. See Documentation/core-api/debugging-via-ohci1394.rst for more info. diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index e59810175262..7937377436d3 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -6,6 +6,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include +#include #include #include #include @@ -76,8 +77,24 @@ MODULE_PARM_DESC(idle_poll_period_usecs, /* * TLS handshake timeout */ -static int tls_handshake_timeout = 10; -module_param(tls_handshake_timeout, int, 0644); +static unsigned int tls_handshake_timeout = 10; + +static int tls_handshake_timeout_set(const char *val, + const struct kernel_param *kp) +{ + return param_set_uint_minmax(val, kp, 0, + min_t(unsigned long, UINT_MAX / MSEC_PER_SEC, + MAX_JIFFY_OFFSET / HZ)); +} + +static const struct kernel_param_ops tls_handshake_timeout_ops = { + .set = tls_handshake_timeout_set, + .get = param_get_uint, +}; + +module_param_cb(tls_handshake_timeout, &tls_handshake_timeout_ops, + &tls_handshake_timeout, 0644); +__MODULE_PARM_TYPE(tls_handshake_timeout, "uint"); MODULE_PARM_DESC(tls_handshake_timeout, "nvme TLS handshake timeout in seconds (default 10)"); #endif @@ -1904,6 +1921,7 @@ static int nvmet_tcp_tls_handshake(struct nvmet_tcp_queue *queue) { int ret = -EOPNOTSUPP; struct tls_handshake_args args; + unsigned int timeout = READ_ONCE(tls_handshake_timeout); if (queue->state != NVMET_TCP_Q_TLS_HANDSHAKE) { pr_warn("cannot start TLS in state %d\n", queue->state); @@ -1917,7 +1935,7 @@ static int nvmet_tcp_tls_handshake(struct nvmet_tcp_queue *queue) args.ta_done = nvmet_tcp_tls_handshake_done; args.ta_data = queue; args.ta_keyring = key_serial(queue->port->nport->keyring); - args.ta_timeout_ms = tls_handshake_timeout * 1000; + args.ta_timeout_ms = timeout * MSEC_PER_SEC; ret = tls_server_hello_psk(&args, GFP_KERNEL); if (ret) { @@ -1925,7 +1943,7 @@ static int nvmet_tcp_tls_handshake(struct nvmet_tcp_queue *queue) pr_err("failed to start TLS, err=%d\n", ret); } else { queue_delayed_work(nvmet_wq, &queue->tls_handshake_tmo_work, - tls_handshake_timeout * HZ); + (unsigned long)timeout * HZ); } return ret; }