In commit 1be37d3b0414 ("can: m_can: fix periph RX path: use
rx-offload to ensure skbs are sent from softirq context") the RX path
for peripheral devices was switched to RX-offload.
Received CAN frames are pushed to RX-offload together with a
timestamp. RX-offload is designed to handle overflows of the timestamp
correctly, if 32 bit timestamps are provided.
The timestamps of m_can core are only 16 bits wide. So this patch
shifts them to full 32 bit before passing them to RX-offload.
Link: https://lore.kernel.org/all/20220612211410.4081390-1-mkl@pengutronix.de
Fixes: 1be37d3b0414 ("can: m_can: fix periph RX path: use rx-offload to ensure skbs are sent from softirq context")
Cc: <stable(a)vger.kernel.org> # 5.13
Cc: Torin Cooper-Bennun <torin(a)maxiluxsystems.com>
Reviewed-by: Chandrasekar Ramakrishnan <rcsekar(a)samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de>
---
drivers/net/can/m_can/m_can.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 03a22d493cf6..7931f9c71ef3 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -529,7 +529,7 @@ static int m_can_read_fifo(struct net_device *dev, u32 rxfs)
/* acknowledge rx fifo 0 */
m_can_write(cdev, M_CAN_RXF0A, fgi);
- timestamp = FIELD_GET(RX_BUF_RXTS_MASK, fifo_header.dlc);
+ timestamp = FIELD_GET(RX_BUF_RXTS_MASK, fifo_header.dlc) << 16;
m_can_receive_skb(cdev, skb, timestamp);
@@ -1030,7 +1030,7 @@ static int m_can_echo_tx_event(struct net_device *dev)
}
msg_mark = FIELD_GET(TX_EVENT_MM_MASK, txe);
- timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe);
+ timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe) << 16;
/* ack txe element */
m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK,
--
2.35.1
In commit df06fd678260 ("can: m_can: m_can_chip_config(): enable and
configure internal timestamps") the timestamping in the m_can core
should be enabled. In peripheral mode, the RX'ed CAN frames, TX
compete frames and error events are sorted by the timestamp.
The above mentioned commit however forgot to enable the timestamping.
Add the missing bits to enable the timestamp counter to the write of
the Timestamp Counter Configuration register.
Link: https://lore.kernel.org/all/20220612212708.4081756-1-mkl@pengutronix.de
Fixes: df06fd678260 ("can: m_can: m_can_chip_config(): enable and configure internal timestamps")
Cc: <stable(a)vger.kernel.org> # 5.13
Cc: Torin Cooper-Bennun <torin(a)maxiluxsystems.com>
Reviewed-by: Chandrasekar Ramakrishnan <rcsekar(a)samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de>
---
drivers/net/can/m_can/m_can.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 5d0c82d8b9a9..03a22d493cf6 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -1351,7 +1351,9 @@ static void m_can_chip_config(struct net_device *dev)
/* enable internal timestamp generation, with a prescalar of 16. The
* prescalar is applied to the nominal bit timing
*/
- m_can_write(cdev, M_CAN_TSCC, FIELD_PREP(TSCC_TCP_MASK, 0xf));
+ m_can_write(cdev, M_CAN_TSCC,
+ FIELD_PREP(TSCC_TCP_MASK, 0xf) |
+ FIELD_PREP(TSCC_TSS_MASK, TSCC_TSS_INTERNAL));
m_can_config_endisable(cdev, false);
--
2.35.1
From: Rhett Aultman <rhett.aultman(a)samsara.com>
The gs_usb driver appears to suffer from a malady common to many USB
CAN adapter drivers in that it performs usb_alloc_coherent() to
allocate a number of USB request blocks (URBs) for RX, and then later
relies on usb_kill_anchored_urbs() to free them, but this doesn't
actually free them. As a result, this may be leaking DMA memory that's
been used by the driver.
This commit is an adaptation of the techniques found in the esd_usb2
driver where a similar design pattern led to a memory leak. It
explicitly frees the RX URBs and their DMA memory via a call to
usb_free_coherent(). Since the RX URBs were allocated in the
gs_can_open(), we remove them in gs_can_close() rather than in the
disconnect function as was done in esd_usb2.
For more information, see the 928150fad41b ("can: esd_usb2: fix memory
leak").
Link: https://lore.kernel.org/all/alpine.DEB.2.22.394.2206031547001.1630869@thela…
Fixes: d08e973a77d1 ("can: gs_usb: Added support for the GS_USB CAN devices")
Cc: stable(a)vger.kernel.org
Signed-off-by: Rhett Aultman <rhett.aultman(a)samsara.com>
Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de>
---
drivers/net/can/usb/gs_usb.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c
index b29ba9138866..d3a658b444b5 100644
--- a/drivers/net/can/usb/gs_usb.c
+++ b/drivers/net/can/usb/gs_usb.c
@@ -268,6 +268,8 @@ struct gs_can {
struct usb_anchor tx_submitted;
atomic_t active_tx_urbs;
+ void *rxbuf[GS_MAX_RX_URBS];
+ dma_addr_t rxbuf_dma[GS_MAX_RX_URBS];
};
/* usb interface struct */
@@ -742,6 +744,7 @@ static int gs_can_open(struct net_device *netdev)
for (i = 0; i < GS_MAX_RX_URBS; i++) {
struct urb *urb;
u8 *buf;
+ dma_addr_t buf_dma;
/* alloc rx urb */
urb = usb_alloc_urb(0, GFP_KERNEL);
@@ -752,7 +755,7 @@ static int gs_can_open(struct net_device *netdev)
buf = usb_alloc_coherent(dev->udev,
dev->parent->hf_size_rx,
GFP_KERNEL,
- &urb->transfer_dma);
+ &buf_dma);
if (!buf) {
netdev_err(netdev,
"No memory left for USB buffer\n");
@@ -760,6 +763,8 @@ static int gs_can_open(struct net_device *netdev)
return -ENOMEM;
}
+ urb->transfer_dma = buf_dma;
+
/* fill, anchor, and submit rx urb */
usb_fill_bulk_urb(urb,
dev->udev,
@@ -781,10 +786,17 @@ static int gs_can_open(struct net_device *netdev)
"usb_submit failed (err=%d)\n", rc);
usb_unanchor_urb(urb);
+ usb_free_coherent(dev->udev,
+ sizeof(struct gs_host_frame),
+ buf,
+ buf_dma);
usb_free_urb(urb);
break;
}
+ dev->rxbuf[i] = buf;
+ dev->rxbuf_dma[i] = buf_dma;
+
/* Drop reference,
* USB core will take care of freeing it
*/
@@ -842,13 +854,20 @@ static int gs_can_close(struct net_device *netdev)
int rc;
struct gs_can *dev = netdev_priv(netdev);
struct gs_usb *parent = dev->parent;
+ unsigned int i;
netif_stop_queue(netdev);
/* Stop polling */
parent->active_channels--;
- if (!parent->active_channels)
+ if (!parent->active_channels) {
usb_kill_anchored_urbs(&parent->rx_submitted);
+ for (i = 0; i < GS_MAX_RX_URBS; i++)
+ usb_free_coherent(dev->udev,
+ sizeof(struct gs_host_frame),
+ dev->rxbuf[i],
+ dev->rxbuf_dma[i]);
+ }
/* Stop sending URBs */
usb_kill_anchored_urbs(&dev->tx_submitted);
--
2.35.1
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From e4f74400308cb8abde5fdc9cad609c2aba32110c Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason(a)zx2c4.com>
Date: Sat, 11 Jun 2022 00:20:23 +0200
Subject: [PATCH] s390/archrandom: simplify back to earlier design and
initialize earlier
s390x appears to present two RNG interfaces:
- a "TRNG" that gathers entropy using some hardware function; and
- a "DRBG" that takes in a seed and expands it.
Previously, the TRNG was wired up to arch_get_random_{long,int}(), but
it was observed that this was being called really frequently, resulting
in high overhead. So it was changed to be wired up to arch_get_random_
seed_{long,int}(), which was a reasonable decision. Later on, the DRBG
was then wired up to arch_get_random_{long,int}(), with a complicated
buffer filling thread, to control overhead and rate.
Fortunately, none of the performance issues matter much now. The RNG
always attempts to use arch_get_random_seed_{long,int}() first, which
means a complicated implementation of arch_get_random_{long,int}() isn't
really valuable or useful to have around. And it's only used when
reseeding, which means it won't hit the high throughput complications
that were faced before.
So this commit returns to an earlier design of just calling the TRNG in
arch_get_random_seed_{long,int}(), and returning false in arch_get_
random_{long,int}().
Part of what makes the simplification possible is that the RNG now seeds
itself using the TRNG at bootup. But this only works if the TRNG is
detected early in boot, before random_init() is called. So this commit
also causes that check to happen in setup_arch().
Cc: stable(a)vger.kernel.org
Cc: Harald Freudenberger <freude(a)linux.ibm.com>
Cc: Ingo Franzki <ifranzki(a)linux.ibm.com>
Cc: Juergen Christ <jchrist(a)linux.ibm.com>
Cc: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason(a)zx2c4.com>
Link: https://lore.kernel.org/r/20220610222023.378448-1-Jason@zx2c4.com
Reviewed-by: Harald Freudenberger <freude(a)linux.ibm.com>
Acked-by: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
diff --git a/arch/s390/crypto/arch_random.c b/arch/s390/crypto/arch_random.c
index 56007c763902..1f2d40993c4d 100644
--- a/arch/s390/crypto/arch_random.c
+++ b/arch/s390/crypto/arch_random.c
@@ -4,232 +4,15 @@
*
* Copyright IBM Corp. 2017, 2020
* Author(s): Harald Freudenberger
- *
- * The s390_arch_random_generate() function may be called from random.c
- * in interrupt context. So this implementation does the best to be very
- * fast. There is a buffer of random data which is asynchronously checked
- * and filled by a workqueue thread.
- * If there are enough bytes in the buffer the s390_arch_random_generate()
- * just delivers these bytes. Otherwise false is returned until the
- * worker thread refills the buffer.
- * The worker fills the rng buffer by pulling fresh entropy from the
- * high quality (but slow) true hardware random generator. This entropy
- * is then spread over the buffer with an pseudo random generator PRNG.
- * As the arch_get_random_seed_long() fetches 8 bytes and the calling
- * function add_interrupt_randomness() counts this as 1 bit entropy the
- * distribution needs to make sure there is in fact 1 bit entropy contained
- * in 8 bytes of the buffer. The current values pull 32 byte entropy
- * and scatter this into a 2048 byte buffer. So 8 byte in the buffer
- * will contain 1 bit of entropy.
- * The worker thread is rescheduled based on the charge level of the
- * buffer but at least with 500 ms delay to avoid too much CPU consumption.
- * So the max. amount of rng data delivered via arch_get_random_seed is
- * limited to 4k bytes per second.
*/
#include <linux/kernel.h>
#include <linux/atomic.h>
#include <linux/random.h>
-#include <linux/slab.h>
#include <linux/static_key.h>
-#include <linux/workqueue.h>
-#include <linux/moduleparam.h>
#include <asm/cpacf.h>
DEFINE_STATIC_KEY_FALSE(s390_arch_random_available);
atomic64_t s390_arch_random_counter = ATOMIC64_INIT(0);
EXPORT_SYMBOL(s390_arch_random_counter);
-
-#define ARCH_REFILL_TICKS (HZ/2)
-#define ARCH_PRNG_SEED_SIZE 32
-#define ARCH_RNG_BUF_SIZE 2048
-
-static DEFINE_SPINLOCK(arch_rng_lock);
-static u8 *arch_rng_buf;
-static unsigned int arch_rng_buf_idx;
-
-static void arch_rng_refill_buffer(struct work_struct *);
-static DECLARE_DELAYED_WORK(arch_rng_work, arch_rng_refill_buffer);
-
-bool s390_arch_random_generate(u8 *buf, unsigned int nbytes)
-{
- /* max hunk is ARCH_RNG_BUF_SIZE */
- if (nbytes > ARCH_RNG_BUF_SIZE)
- return false;
-
- /* lock rng buffer */
- if (!spin_trylock(&arch_rng_lock))
- return false;
-
- /* try to resolve the requested amount of bytes from the buffer */
- arch_rng_buf_idx -= nbytes;
- if (arch_rng_buf_idx < ARCH_RNG_BUF_SIZE) {
- memcpy(buf, arch_rng_buf + arch_rng_buf_idx, nbytes);
- atomic64_add(nbytes, &s390_arch_random_counter);
- spin_unlock(&arch_rng_lock);
- return true;
- }
-
- /* not enough bytes in rng buffer, refill is done asynchronously */
- spin_unlock(&arch_rng_lock);
-
- return false;
-}
-EXPORT_SYMBOL(s390_arch_random_generate);
-
-static void arch_rng_refill_buffer(struct work_struct *unused)
-{
- unsigned int delay = ARCH_REFILL_TICKS;
-
- spin_lock(&arch_rng_lock);
- if (arch_rng_buf_idx > ARCH_RNG_BUF_SIZE) {
- /* buffer is exhausted and needs refill */
- u8 seed[ARCH_PRNG_SEED_SIZE];
- u8 prng_wa[240];
- /* fetch ARCH_PRNG_SEED_SIZE bytes of entropy */
- cpacf_trng(NULL, 0, seed, sizeof(seed));
- /* blow this entropy up to ARCH_RNG_BUF_SIZE with PRNG */
- memset(prng_wa, 0, sizeof(prng_wa));
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_SEED,
- &prng_wa, NULL, 0, seed, sizeof(seed));
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_GEN,
- &prng_wa, arch_rng_buf, ARCH_RNG_BUF_SIZE, NULL, 0);
- arch_rng_buf_idx = ARCH_RNG_BUF_SIZE;
- }
- delay += (ARCH_REFILL_TICKS * arch_rng_buf_idx) / ARCH_RNG_BUF_SIZE;
- spin_unlock(&arch_rng_lock);
-
- /* kick next check */
- queue_delayed_work(system_long_wq, &arch_rng_work, delay);
-}
-
-/*
- * Here follows the implementation of s390_arch_get_random_long().
- *
- * The random longs to be pulled by arch_get_random_long() are
- * prepared in an 4K buffer which is filled from the NIST 800-90
- * compliant s390 drbg. By default the random long buffer is refilled
- * 256 times before the drbg itself needs a reseed. The reseed of the
- * drbg is done with 32 bytes fetched from the high quality (but slow)
- * trng which is assumed to deliver 100% entropy. So the 32 * 8 = 256
- * bits of entropy are spread over 256 * 4KB = 1MB serving 131072
- * arch_get_random_long() invocations before reseeded.
- *
- * How often the 4K random long buffer is refilled with the drbg
- * before the drbg is reseeded can be adjusted. There is a module
- * parameter 's390_arch_rnd_long_drbg_reseed' accessible via
- * /sys/module/arch_random/parameters/rndlong_drbg_reseed
- * or as kernel command line parameter
- * arch_random.rndlong_drbg_reseed=<value>
- * This parameter tells how often the drbg fills the 4K buffer before
- * it is re-seeded by fresh entropy from the trng.
- * A value of 16 results in reseeding the drbg at every 16 * 4 KB = 64
- * KB with 32 bytes of fresh entropy pulled from the trng. So a value
- * of 16 would result in 256 bits entropy per 64 KB.
- * A value of 256 results in 1MB of drbg output before a reseed of the
- * drbg is done. So this would spread the 256 bits of entropy among 1MB.
- * Setting this parameter to 0 forces the reseed to take place every
- * time the 4K buffer is depleted, so the entropy rises to 256 bits
- * entropy per 4K or 0.5 bit entropy per arch_get_random_long(). With
- * setting this parameter to negative values all this effort is
- * disabled, arch_get_random long() returns false and thus indicating
- * that the arch_get_random_long() feature is disabled at all.
- */
-
-static unsigned long rndlong_buf[512];
-static DEFINE_SPINLOCK(rndlong_lock);
-static int rndlong_buf_index;
-
-static int rndlong_drbg_reseed = 256;
-module_param_named(rndlong_drbg_reseed, rndlong_drbg_reseed, int, 0600);
-MODULE_PARM_DESC(rndlong_drbg_reseed, "s390 arch_get_random_long() drbg reseed");
-
-static inline void refill_rndlong_buf(void)
-{
- static u8 prng_ws[240];
- static int drbg_counter;
-
- if (--drbg_counter < 0) {
- /* need to re-seed the drbg */
- u8 seed[32];
-
- /* fetch seed from trng */
- cpacf_trng(NULL, 0, seed, sizeof(seed));
- /* seed drbg */
- memset(prng_ws, 0, sizeof(prng_ws));
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_SEED,
- &prng_ws, NULL, 0, seed, sizeof(seed));
- /* re-init counter for drbg */
- drbg_counter = rndlong_drbg_reseed;
- }
-
- /* fill the arch_get_random_long buffer from drbg */
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_GEN, &prng_ws,
- (u8 *) rndlong_buf, sizeof(rndlong_buf),
- NULL, 0);
-}
-
-bool s390_arch_get_random_long(unsigned long *v)
-{
- bool rc = false;
- unsigned long flags;
-
- /* arch_get_random_long() disabled ? */
- if (rndlong_drbg_reseed < 0)
- return false;
-
- /* try to lock the random long lock */
- if (!spin_trylock_irqsave(&rndlong_lock, flags))
- return false;
-
- if (--rndlong_buf_index >= 0) {
- /* deliver next long value from the buffer */
- *v = rndlong_buf[rndlong_buf_index];
- rc = true;
- goto out;
- }
-
- /* buffer is depleted and needs refill */
- if (in_interrupt()) {
- /* delay refill in interrupt context to next caller */
- rndlong_buf_index = 0;
- goto out;
- }
-
- /* refill random long buffer */
- refill_rndlong_buf();
- rndlong_buf_index = ARRAY_SIZE(rndlong_buf);
-
- /* and provide one random long */
- *v = rndlong_buf[--rndlong_buf_index];
- rc = true;
-
-out:
- spin_unlock_irqrestore(&rndlong_lock, flags);
- return rc;
-}
-EXPORT_SYMBOL(s390_arch_get_random_long);
-
-static int __init s390_arch_random_init(void)
-{
- /* all the needed PRNO subfunctions available ? */
- if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG) &&
- cpacf_query_func(CPACF_PRNO, CPACF_PRNO_SHA512_DRNG_GEN)) {
-
- /* alloc arch random working buffer */
- arch_rng_buf = kmalloc(ARCH_RNG_BUF_SIZE, GFP_KERNEL);
- if (!arch_rng_buf)
- return -ENOMEM;
-
- /* kick worker queue job to fill the random buffer */
- queue_delayed_work(system_long_wq,
- &arch_rng_work, ARCH_REFILL_TICKS);
-
- /* enable arch random to the outside world */
- static_branch_enable(&s390_arch_random_available);
- }
-
- return 0;
-}
-arch_initcall(s390_arch_random_init);
diff --git a/arch/s390/include/asm/archrandom.h b/arch/s390/include/asm/archrandom.h
index 5dc712fde3c7..2c6e1c6ecbe7 100644
--- a/arch/s390/include/asm/archrandom.h
+++ b/arch/s390/include/asm/archrandom.h
@@ -15,17 +15,13 @@
#include <linux/static_key.h>
#include <linux/atomic.h>
+#include <asm/cpacf.h>
DECLARE_STATIC_KEY_FALSE(s390_arch_random_available);
extern atomic64_t s390_arch_random_counter;
-bool s390_arch_get_random_long(unsigned long *v);
-bool s390_arch_random_generate(u8 *buf, unsigned int nbytes);
-
static inline bool __must_check arch_get_random_long(unsigned long *v)
{
- if (static_branch_likely(&s390_arch_random_available))
- return s390_arch_get_random_long(v);
return false;
}
@@ -37,7 +33,9 @@ static inline bool __must_check arch_get_random_int(unsigned int *v)
static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
{
if (static_branch_likely(&s390_arch_random_available)) {
- return s390_arch_random_generate((u8 *)v, sizeof(*v));
+ cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v));
+ atomic64_add(sizeof(*v), &s390_arch_random_counter);
+ return true;
}
return false;
}
@@ -45,7 +43,9 @@ static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
{
if (static_branch_likely(&s390_arch_random_available)) {
- return s390_arch_random_generate((u8 *)v, sizeof(*v));
+ cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v));
+ atomic64_add(sizeof(*v), &s390_arch_random_counter);
+ return true;
}
return false;
}
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 8d91eccc0963..0a37f5de2863 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -875,6 +875,11 @@ static void __init setup_randomness(void)
if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
memblock_free(vmms, PAGE_SIZE);
+
+#ifdef CONFIG_ARCH_RANDOM
+ if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
+ static_branch_enable(&s390_arch_random_available);
+#endif
}
/*
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From e4f74400308cb8abde5fdc9cad609c2aba32110c Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason(a)zx2c4.com>
Date: Sat, 11 Jun 2022 00:20:23 +0200
Subject: [PATCH] s390/archrandom: simplify back to earlier design and
initialize earlier
s390x appears to present two RNG interfaces:
- a "TRNG" that gathers entropy using some hardware function; and
- a "DRBG" that takes in a seed and expands it.
Previously, the TRNG was wired up to arch_get_random_{long,int}(), but
it was observed that this was being called really frequently, resulting
in high overhead. So it was changed to be wired up to arch_get_random_
seed_{long,int}(), which was a reasonable decision. Later on, the DRBG
was then wired up to arch_get_random_{long,int}(), with a complicated
buffer filling thread, to control overhead and rate.
Fortunately, none of the performance issues matter much now. The RNG
always attempts to use arch_get_random_seed_{long,int}() first, which
means a complicated implementation of arch_get_random_{long,int}() isn't
really valuable or useful to have around. And it's only used when
reseeding, which means it won't hit the high throughput complications
that were faced before.
So this commit returns to an earlier design of just calling the TRNG in
arch_get_random_seed_{long,int}(), and returning false in arch_get_
random_{long,int}().
Part of what makes the simplification possible is that the RNG now seeds
itself using the TRNG at bootup. But this only works if the TRNG is
detected early in boot, before random_init() is called. So this commit
also causes that check to happen in setup_arch().
Cc: stable(a)vger.kernel.org
Cc: Harald Freudenberger <freude(a)linux.ibm.com>
Cc: Ingo Franzki <ifranzki(a)linux.ibm.com>
Cc: Juergen Christ <jchrist(a)linux.ibm.com>
Cc: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason(a)zx2c4.com>
Link: https://lore.kernel.org/r/20220610222023.378448-1-Jason@zx2c4.com
Reviewed-by: Harald Freudenberger <freude(a)linux.ibm.com>
Acked-by: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
diff --git a/arch/s390/crypto/arch_random.c b/arch/s390/crypto/arch_random.c
index 56007c763902..1f2d40993c4d 100644
--- a/arch/s390/crypto/arch_random.c
+++ b/arch/s390/crypto/arch_random.c
@@ -4,232 +4,15 @@
*
* Copyright IBM Corp. 2017, 2020
* Author(s): Harald Freudenberger
- *
- * The s390_arch_random_generate() function may be called from random.c
- * in interrupt context. So this implementation does the best to be very
- * fast. There is a buffer of random data which is asynchronously checked
- * and filled by a workqueue thread.
- * If there are enough bytes in the buffer the s390_arch_random_generate()
- * just delivers these bytes. Otherwise false is returned until the
- * worker thread refills the buffer.
- * The worker fills the rng buffer by pulling fresh entropy from the
- * high quality (but slow) true hardware random generator. This entropy
- * is then spread over the buffer with an pseudo random generator PRNG.
- * As the arch_get_random_seed_long() fetches 8 bytes and the calling
- * function add_interrupt_randomness() counts this as 1 bit entropy the
- * distribution needs to make sure there is in fact 1 bit entropy contained
- * in 8 bytes of the buffer. The current values pull 32 byte entropy
- * and scatter this into a 2048 byte buffer. So 8 byte in the buffer
- * will contain 1 bit of entropy.
- * The worker thread is rescheduled based on the charge level of the
- * buffer but at least with 500 ms delay to avoid too much CPU consumption.
- * So the max. amount of rng data delivered via arch_get_random_seed is
- * limited to 4k bytes per second.
*/
#include <linux/kernel.h>
#include <linux/atomic.h>
#include <linux/random.h>
-#include <linux/slab.h>
#include <linux/static_key.h>
-#include <linux/workqueue.h>
-#include <linux/moduleparam.h>
#include <asm/cpacf.h>
DEFINE_STATIC_KEY_FALSE(s390_arch_random_available);
atomic64_t s390_arch_random_counter = ATOMIC64_INIT(0);
EXPORT_SYMBOL(s390_arch_random_counter);
-
-#define ARCH_REFILL_TICKS (HZ/2)
-#define ARCH_PRNG_SEED_SIZE 32
-#define ARCH_RNG_BUF_SIZE 2048
-
-static DEFINE_SPINLOCK(arch_rng_lock);
-static u8 *arch_rng_buf;
-static unsigned int arch_rng_buf_idx;
-
-static void arch_rng_refill_buffer(struct work_struct *);
-static DECLARE_DELAYED_WORK(arch_rng_work, arch_rng_refill_buffer);
-
-bool s390_arch_random_generate(u8 *buf, unsigned int nbytes)
-{
- /* max hunk is ARCH_RNG_BUF_SIZE */
- if (nbytes > ARCH_RNG_BUF_SIZE)
- return false;
-
- /* lock rng buffer */
- if (!spin_trylock(&arch_rng_lock))
- return false;
-
- /* try to resolve the requested amount of bytes from the buffer */
- arch_rng_buf_idx -= nbytes;
- if (arch_rng_buf_idx < ARCH_RNG_BUF_SIZE) {
- memcpy(buf, arch_rng_buf + arch_rng_buf_idx, nbytes);
- atomic64_add(nbytes, &s390_arch_random_counter);
- spin_unlock(&arch_rng_lock);
- return true;
- }
-
- /* not enough bytes in rng buffer, refill is done asynchronously */
- spin_unlock(&arch_rng_lock);
-
- return false;
-}
-EXPORT_SYMBOL(s390_arch_random_generate);
-
-static void arch_rng_refill_buffer(struct work_struct *unused)
-{
- unsigned int delay = ARCH_REFILL_TICKS;
-
- spin_lock(&arch_rng_lock);
- if (arch_rng_buf_idx > ARCH_RNG_BUF_SIZE) {
- /* buffer is exhausted and needs refill */
- u8 seed[ARCH_PRNG_SEED_SIZE];
- u8 prng_wa[240];
- /* fetch ARCH_PRNG_SEED_SIZE bytes of entropy */
- cpacf_trng(NULL, 0, seed, sizeof(seed));
- /* blow this entropy up to ARCH_RNG_BUF_SIZE with PRNG */
- memset(prng_wa, 0, sizeof(prng_wa));
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_SEED,
- &prng_wa, NULL, 0, seed, sizeof(seed));
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_GEN,
- &prng_wa, arch_rng_buf, ARCH_RNG_BUF_SIZE, NULL, 0);
- arch_rng_buf_idx = ARCH_RNG_BUF_SIZE;
- }
- delay += (ARCH_REFILL_TICKS * arch_rng_buf_idx) / ARCH_RNG_BUF_SIZE;
- spin_unlock(&arch_rng_lock);
-
- /* kick next check */
- queue_delayed_work(system_long_wq, &arch_rng_work, delay);
-}
-
-/*
- * Here follows the implementation of s390_arch_get_random_long().
- *
- * The random longs to be pulled by arch_get_random_long() are
- * prepared in an 4K buffer which is filled from the NIST 800-90
- * compliant s390 drbg. By default the random long buffer is refilled
- * 256 times before the drbg itself needs a reseed. The reseed of the
- * drbg is done with 32 bytes fetched from the high quality (but slow)
- * trng which is assumed to deliver 100% entropy. So the 32 * 8 = 256
- * bits of entropy are spread over 256 * 4KB = 1MB serving 131072
- * arch_get_random_long() invocations before reseeded.
- *
- * How often the 4K random long buffer is refilled with the drbg
- * before the drbg is reseeded can be adjusted. There is a module
- * parameter 's390_arch_rnd_long_drbg_reseed' accessible via
- * /sys/module/arch_random/parameters/rndlong_drbg_reseed
- * or as kernel command line parameter
- * arch_random.rndlong_drbg_reseed=<value>
- * This parameter tells how often the drbg fills the 4K buffer before
- * it is re-seeded by fresh entropy from the trng.
- * A value of 16 results in reseeding the drbg at every 16 * 4 KB = 64
- * KB with 32 bytes of fresh entropy pulled from the trng. So a value
- * of 16 would result in 256 bits entropy per 64 KB.
- * A value of 256 results in 1MB of drbg output before a reseed of the
- * drbg is done. So this would spread the 256 bits of entropy among 1MB.
- * Setting this parameter to 0 forces the reseed to take place every
- * time the 4K buffer is depleted, so the entropy rises to 256 bits
- * entropy per 4K or 0.5 bit entropy per arch_get_random_long(). With
- * setting this parameter to negative values all this effort is
- * disabled, arch_get_random long() returns false and thus indicating
- * that the arch_get_random_long() feature is disabled at all.
- */
-
-static unsigned long rndlong_buf[512];
-static DEFINE_SPINLOCK(rndlong_lock);
-static int rndlong_buf_index;
-
-static int rndlong_drbg_reseed = 256;
-module_param_named(rndlong_drbg_reseed, rndlong_drbg_reseed, int, 0600);
-MODULE_PARM_DESC(rndlong_drbg_reseed, "s390 arch_get_random_long() drbg reseed");
-
-static inline void refill_rndlong_buf(void)
-{
- static u8 prng_ws[240];
- static int drbg_counter;
-
- if (--drbg_counter < 0) {
- /* need to re-seed the drbg */
- u8 seed[32];
-
- /* fetch seed from trng */
- cpacf_trng(NULL, 0, seed, sizeof(seed));
- /* seed drbg */
- memset(prng_ws, 0, sizeof(prng_ws));
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_SEED,
- &prng_ws, NULL, 0, seed, sizeof(seed));
- /* re-init counter for drbg */
- drbg_counter = rndlong_drbg_reseed;
- }
-
- /* fill the arch_get_random_long buffer from drbg */
- cpacf_prno(CPACF_PRNO_SHA512_DRNG_GEN, &prng_ws,
- (u8 *) rndlong_buf, sizeof(rndlong_buf),
- NULL, 0);
-}
-
-bool s390_arch_get_random_long(unsigned long *v)
-{
- bool rc = false;
- unsigned long flags;
-
- /* arch_get_random_long() disabled ? */
- if (rndlong_drbg_reseed < 0)
- return false;
-
- /* try to lock the random long lock */
- if (!spin_trylock_irqsave(&rndlong_lock, flags))
- return false;
-
- if (--rndlong_buf_index >= 0) {
- /* deliver next long value from the buffer */
- *v = rndlong_buf[rndlong_buf_index];
- rc = true;
- goto out;
- }
-
- /* buffer is depleted and needs refill */
- if (in_interrupt()) {
- /* delay refill in interrupt context to next caller */
- rndlong_buf_index = 0;
- goto out;
- }
-
- /* refill random long buffer */
- refill_rndlong_buf();
- rndlong_buf_index = ARRAY_SIZE(rndlong_buf);
-
- /* and provide one random long */
- *v = rndlong_buf[--rndlong_buf_index];
- rc = true;
-
-out:
- spin_unlock_irqrestore(&rndlong_lock, flags);
- return rc;
-}
-EXPORT_SYMBOL(s390_arch_get_random_long);
-
-static int __init s390_arch_random_init(void)
-{
- /* all the needed PRNO subfunctions available ? */
- if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG) &&
- cpacf_query_func(CPACF_PRNO, CPACF_PRNO_SHA512_DRNG_GEN)) {
-
- /* alloc arch random working buffer */
- arch_rng_buf = kmalloc(ARCH_RNG_BUF_SIZE, GFP_KERNEL);
- if (!arch_rng_buf)
- return -ENOMEM;
-
- /* kick worker queue job to fill the random buffer */
- queue_delayed_work(system_long_wq,
- &arch_rng_work, ARCH_REFILL_TICKS);
-
- /* enable arch random to the outside world */
- static_branch_enable(&s390_arch_random_available);
- }
-
- return 0;
-}
-arch_initcall(s390_arch_random_init);
diff --git a/arch/s390/include/asm/archrandom.h b/arch/s390/include/asm/archrandom.h
index 5dc712fde3c7..2c6e1c6ecbe7 100644
--- a/arch/s390/include/asm/archrandom.h
+++ b/arch/s390/include/asm/archrandom.h
@@ -15,17 +15,13 @@
#include <linux/static_key.h>
#include <linux/atomic.h>
+#include <asm/cpacf.h>
DECLARE_STATIC_KEY_FALSE(s390_arch_random_available);
extern atomic64_t s390_arch_random_counter;
-bool s390_arch_get_random_long(unsigned long *v);
-bool s390_arch_random_generate(u8 *buf, unsigned int nbytes);
-
static inline bool __must_check arch_get_random_long(unsigned long *v)
{
- if (static_branch_likely(&s390_arch_random_available))
- return s390_arch_get_random_long(v);
return false;
}
@@ -37,7 +33,9 @@ static inline bool __must_check arch_get_random_int(unsigned int *v)
static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
{
if (static_branch_likely(&s390_arch_random_available)) {
- return s390_arch_random_generate((u8 *)v, sizeof(*v));
+ cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v));
+ atomic64_add(sizeof(*v), &s390_arch_random_counter);
+ return true;
}
return false;
}
@@ -45,7 +43,9 @@ static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
{
if (static_branch_likely(&s390_arch_random_available)) {
- return s390_arch_random_generate((u8 *)v, sizeof(*v));
+ cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v));
+ atomic64_add(sizeof(*v), &s390_arch_random_counter);
+ return true;
}
return false;
}
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 8d91eccc0963..0a37f5de2863 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -875,6 +875,11 @@ static void __init setup_randomness(void)
if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
memblock_free(vmms, PAGE_SIZE);
+
+#ifdef CONFIG_ARCH_RANDOM
+ if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
+ static_branch_enable(&s390_arch_random_available);
+#endif
}
/*
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f3eac426657d985b97c92fa5f7ae1d43f04721f3 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason(a)zx2c4.com>
Date: Tue, 21 Jun 2022 16:08:49 +0200
Subject: [PATCH] powerpc/powernv: wire up rng during setup_arch
The platform's RNG must be available before random_init() in order to be
useful for initial seeding, which in turn means that it needs to be
called from setup_arch(), rather than from an init call.
Complicating things, however, is that POWER8 systems need some per-cpu
state and kmalloc, which isn't available at this stage. So we split
things up into an early phase and a later opportunistic phase. This
commit also removes some noisy log messages that don't add much.
Fixes: a4da0d50b2a0 ("powerpc: Implement arch_get_random_long/int() for powernv")
Cc: stable(a)vger.kernel.org # v3.13+
Signed-off-by: Jason A. Donenfeld <Jason(a)zx2c4.com>
Reviewed-by: Christophe Leroy <christophe.leroy(a)csgroup.eu>
[mpe: Add of_node_put(), use pnv naming, minor change log editing]
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
Link: https://lore.kernel.org/r/20220621140849.127227-1-Jason@zx2c4.com
diff --git a/arch/powerpc/platforms/powernv/powernv.h b/arch/powerpc/platforms/powernv/powernv.h
index e297bf4abfcb..866efdc103fd 100644
--- a/arch/powerpc/platforms/powernv/powernv.h
+++ b/arch/powerpc/platforms/powernv/powernv.h
@@ -42,4 +42,6 @@ ssize_t memcons_copy(struct memcons *mc, char *to, loff_t pos, size_t count);
u32 __init memcons_get_size(struct memcons *mc);
struct memcons *__init memcons_init(struct device_node *node, const char *mc_prop_name);
+void pnv_rng_init(void);
+
#endif /* _POWERNV_H */
diff --git a/arch/powerpc/platforms/powernv/rng.c b/arch/powerpc/platforms/powernv/rng.c
index e3d44b36ae98..463c78c52cc5 100644
--- a/arch/powerpc/platforms/powernv/rng.c
+++ b/arch/powerpc/platforms/powernv/rng.c
@@ -17,6 +17,7 @@
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/smp.h>
+#include "powernv.h"
#define DARN_ERR 0xFFFFFFFFFFFFFFFFul
@@ -28,7 +29,6 @@ struct powernv_rng {
static DEFINE_PER_CPU(struct powernv_rng *, powernv_rng);
-
int powernv_hwrng_present(void)
{
struct powernv_rng *rng;
@@ -98,9 +98,6 @@ static int __init initialise_darn(void)
return 0;
}
}
-
- pr_warn("Unable to use DARN for get_random_seed()\n");
-
return -EIO;
}
@@ -163,32 +160,55 @@ static __init int rng_create(struct device_node *dn)
rng_init_per_cpu(rng, dn);
- pr_info_once("Registering arch random hook.\n");
-
ppc_md.get_random_seed = powernv_get_random_long;
return 0;
}
-static __init int rng_init(void)
+static int __init pnv_get_random_long_early(unsigned long *v)
{
struct device_node *dn;
- int rc;
+
+ if (!slab_is_available())
+ return 0;
+
+ if (cmpxchg(&ppc_md.get_random_seed, pnv_get_random_long_early,
+ NULL) != pnv_get_random_long_early)
+ return 0;
for_each_compatible_node(dn, NULL, "ibm,power-rng") {
- rc = rng_create(dn);
- if (rc) {
- pr_err("Failed creating rng for %pOF (%d).\n",
- dn, rc);
+ if (rng_create(dn))
continue;
- }
-
/* Create devices for hwrng driver */
of_platform_device_create(dn, NULL, NULL);
}
- initialise_darn();
+ if (!ppc_md.get_random_seed)
+ return 0;
+ return ppc_md.get_random_seed(v);
+}
+
+void __init pnv_rng_init(void)
+{
+ struct device_node *dn;
+ /* Prefer darn over the rest. */
+ if (!initialise_darn())
+ return;
+
+ dn = of_find_compatible_node(NULL, NULL, "ibm,power-rng");
+ if (dn)
+ ppc_md.get_random_seed = pnv_get_random_long_early;
+
+ of_node_put(dn);
+}
+
+static int __init pnv_rng_late_init(void)
+{
+ unsigned long v;
+ /* In case it wasn't called during init for some other reason. */
+ if (ppc_md.get_random_seed == pnv_get_random_long_early)
+ pnv_get_random_long_early(&v);
return 0;
}
-machine_subsys_initcall(powernv, rng_init);
+machine_subsys_initcall(powernv, pnv_rng_late_init);
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 824c3ad7a0fa..dac545aa0308 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -203,6 +203,8 @@ static void __init pnv_setup_arch(void)
pnv_check_guarded_cores();
/* XXX PMCS */
+
+ pnv_rng_init();
}
static void __init pnv_init(void)
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fd37c2ecb21f7aee04ccca5f561469f07d00063c Mon Sep 17 00:00:00 2001
From: Mat Martineau <mathew.j.martineau(a)linux.intel.com>
Date: Mon, 27 Jun 2022 18:02:43 -0700
Subject: [PATCH] selftests: mptcp: Initialize variables to quiet gcc 12
warnings
In a few MPTCP selftest tools, gcc 12 complains that the 'sock' variable
might be used uninitialized. This is a false positive because the only
code path that could lead to uninitialized access is where getaddrinfo()
fails, but the local xgetaddrinfo() wrapper exits if such a failure
occurs.
Initialize the 'sock' variable anyway to allow the tools to build with
gcc 12.
Fixes: 048d19d444be ("mptcp: add basic kselftest for mptcp")
Acked-by: Paolo Abeni <pabeni(a)redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau(a)linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.c b/tools/testing/selftests/net/mptcp/mptcp_connect.c
index 8628aa61b763..e2ea6c126c99 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.c
@@ -265,7 +265,7 @@ static void sock_test_tcpulp(int sock, int proto, unsigned int line)
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
- int sock;
+ int sock = -1;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
diff --git a/tools/testing/selftests/net/mptcp/mptcp_inq.c b/tools/testing/selftests/net/mptcp/mptcp_inq.c
index 29f75e2a1116..8672d898f8cd 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_inq.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_inq.c
@@ -88,7 +88,7 @@ static void xgetaddrinfo(const char *node, const char *service,
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
- int sock;
+ int sock = -1;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
index ac9a4d9c1764..ae61f39556ca 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
@@ -136,7 +136,7 @@ static void xgetaddrinfo(const char *node, const char *service,
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
- int sock;
+ int sock = -1;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fd37c2ecb21f7aee04ccca5f561469f07d00063c Mon Sep 17 00:00:00 2001
From: Mat Martineau <mathew.j.martineau(a)linux.intel.com>
Date: Mon, 27 Jun 2022 18:02:43 -0700
Subject: [PATCH] selftests: mptcp: Initialize variables to quiet gcc 12
warnings
In a few MPTCP selftest tools, gcc 12 complains that the 'sock' variable
might be used uninitialized. This is a false positive because the only
code path that could lead to uninitialized access is where getaddrinfo()
fails, but the local xgetaddrinfo() wrapper exits if such a failure
occurs.
Initialize the 'sock' variable anyway to allow the tools to build with
gcc 12.
Fixes: 048d19d444be ("mptcp: add basic kselftest for mptcp")
Acked-by: Paolo Abeni <pabeni(a)redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau(a)linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.c b/tools/testing/selftests/net/mptcp/mptcp_connect.c
index 8628aa61b763..e2ea6c126c99 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.c
@@ -265,7 +265,7 @@ static void sock_test_tcpulp(int sock, int proto, unsigned int line)
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
- int sock;
+ int sock = -1;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
diff --git a/tools/testing/selftests/net/mptcp/mptcp_inq.c b/tools/testing/selftests/net/mptcp/mptcp_inq.c
index 29f75e2a1116..8672d898f8cd 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_inq.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_inq.c
@@ -88,7 +88,7 @@ static void xgetaddrinfo(const char *node, const char *service,
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
- int sock;
+ int sock = -1;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
index ac9a4d9c1764..ae61f39556ca 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
@@ -136,7 +136,7 @@ static void xgetaddrinfo(const char *node, const char *service,
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
- int sock;
+ int sock = -1;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,