From: Marek Vasut <marex@nabladev.com> stable inclusion from stable-v6.6.140 commit 640a7631d31db87d5fa1b34cea44a99b6e78854b category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/15276 CVE: CVE-2026-46031 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 5c9fcac3c872224316714d0d8914d9af16c76a6d upstream. If the driver executes ks8851_irq() AND a TX packet has been sent, then the driver enables TX queue via netif_wake_queue() which schedules TX softirq to queue packets for this device. If CONFIG_PREEMPT_RT=y is set AND a packet has also been received by the MAC, then ks8851_rx_pkts() calls netdev_alloc_skb_ip_align() to allocate SKBs for the received packets. If netdev_alloc_skb_ip_align() is called with BH enabled, then local_bh_enable() at the end of netdev_alloc_skb_ip_align() will trigger the pending softirq processing, which may ultimately call the .xmit callback ks8851_start_xmit_par(). The ks8851_start_xmit_par() will try to lock struct ks8851_net_par .lock spinlock, which is already locked by ks8851_irq() from which ks8851_start_xmit_par() was called. This leads to a deadlock, which is reported by the kernel, including a trace listed below. If CONFIG_PREEMPT_RT is not set, then since commit 0913ec336a6c0 ("net: ks8851: Fix deadlock with the SPI chip variant") the deadlock can also be triggered without received packet in the RX FIFO. The pending softirqs will be processed on return from spin_unlock_bh(&ks->statelock) in ks8851_irq(), which triggers the deadlock as well. Fix the problem by disabling BH around critical sections, including the IRQ handler, thus preventing the net_tx_action() softirq from triggering during these critical sections. The net_tx_action() softirq is triggered once BH are re-enabled and at the end of the IRQ handler, once all the other IRQ handler actions have been completed. __schedule from schedule_rtlock+0x1c/0x34 schedule_rtlock from rtlock_slowlock_locked+0x548/0x904 rtlock_slowlock_locked from rt_spin_lock+0x60/0x9c rt_spin_lock from ks8851_start_xmit_par+0x74/0x1a8 ks8851_start_xmit_par from netdev_start_xmit+0x20/0x44 netdev_start_xmit from dev_hard_start_xmit+0xd0/0x188 dev_hard_start_xmit from sch_direct_xmit+0xb8/0x25c sch_direct_xmit from __qdisc_run+0x1f8/0x4ec __qdisc_run from qdisc_run+0x1c/0x28 qdisc_run from net_tx_action+0x1f0/0x268 net_tx_action from handle_softirqs+0x1a4/0x270 handle_softirqs from __local_bh_enable_ip+0xcc/0xe0 __local_bh_enable_ip from __alloc_skb+0xd8/0x128 __alloc_skb from __netdev_alloc_skb+0x3c/0x19c __netdev_alloc_skb from ks8851_irq+0x388/0x4d4 ks8851_irq from irq_thread_fn+0x24/0x64 irq_thread_fn from irq_thread+0x178/0x28c irq_thread from kthread+0x12c/0x138 kthread from ret_from_fork+0x14/0x28 Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Fixes: e0863634bf9f ("net: ks8851: Queue RX packets in IRQ handler instead of disabling BHs") Cc: stable@vger.kernel.org Signed-off-by: Marek Vasut <marex@nabladev.com> Link: https://patch.msgid.link/20260415231020.455298-1-marex@nabladev.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> --- drivers/net/ethernet/micrel/ks8851.h | 6 +- drivers/net/ethernet/micrel/ks8851_common.c | 64 +++++++++------------ drivers/net/ethernet/micrel/ks8851_par.c | 15 ++--- drivers/net/ethernet/micrel/ks8851_spi.c | 11 ++-- 4 files changed, 38 insertions(+), 58 deletions(-) diff --git a/drivers/net/ethernet/micrel/ks8851.h b/drivers/net/ethernet/micrel/ks8851.h index 31f75b4a67fd..b795a3a60571 100644 --- a/drivers/net/ethernet/micrel/ks8851.h +++ b/drivers/net/ethernet/micrel/ks8851.h @@ -406,14 +406,12 @@ struct ks8851_net { struct regulator *vdd_reg; struct regulator *vdd_io; struct gpio_desc *gpio; struct mii_bus *mii_bus; - void (*lock)(struct ks8851_net *ks, - unsigned long *flags); - void (*unlock)(struct ks8851_net *ks, - unsigned long *flags); + void (*lock)(struct ks8851_net *ks); + void (*unlock)(struct ks8851_net *ks); unsigned int (*rdreg16)(struct ks8851_net *ks, unsigned int reg); void (*wrreg16)(struct ks8851_net *ks, unsigned int reg, unsigned int val); void (*rdfifo)(struct ks8851_net *ks, u8 *buff, diff --git a/drivers/net/ethernet/micrel/ks8851_common.c b/drivers/net/ethernet/micrel/ks8851_common.c index 7fa1820db9cc..8e06656a06c1 100644 --- a/drivers/net/ethernet/micrel/ks8851_common.c +++ b/drivers/net/ethernet/micrel/ks8851_common.c @@ -26,29 +26,27 @@ #include "ks8851.h" /** * ks8851_lock - register access lock * @ks: The chip state - * @flags: Spinlock flags * * Claim chip register access lock */ -static void ks8851_lock(struct ks8851_net *ks, unsigned long *flags) +static void ks8851_lock(struct ks8851_net *ks) { - ks->lock(ks, flags); + ks->lock(ks); } /** * ks8851_unlock - register access unlock * @ks: The chip state - * @flags: Spinlock flags * * Release chip register access lock */ -static void ks8851_unlock(struct ks8851_net *ks, unsigned long *flags) +static void ks8851_unlock(struct ks8851_net *ks) { - ks->unlock(ks, flags); + ks->unlock(ks); } /** * ks8851_wrreg16 - write 16bit register value to chip * @ks: The chip state @@ -127,15 +125,14 @@ static void ks8851_set_powermode(struct ks8851_net *ks, unsigned pwrmode) * shutdown the RXQ process whilst setting this. */ static int ks8851_write_mac_addr(struct net_device *dev) { struct ks8851_net *ks = netdev_priv(dev); - unsigned long flags; u16 val; int i; - ks8851_lock(ks, &flags); + ks8851_lock(ks); /* * Wake up chip in case it was powered off when stopped; otherwise, * the first write to the MAC address does not take effect. */ @@ -147,11 +144,11 @@ static int ks8851_write_mac_addr(struct net_device *dev) } if (!netif_running(dev)) ks8851_set_powermode(ks, PMECR_PM_SOFTDOWN); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); return 0; } /** @@ -161,25 +158,24 @@ static int ks8851_write_mac_addr(struct net_device *dev) * Update our copy of the KS8851 MAC address from the registers of @dev. */ static void ks8851_read_mac_addr(struct net_device *dev) { struct ks8851_net *ks = netdev_priv(dev); - unsigned long flags; u8 addr[ETH_ALEN]; u16 reg; int i; - ks8851_lock(ks, &flags); + ks8851_lock(ks); for (i = 0; i < ETH_ALEN; i += 2) { reg = ks8851_rdreg16(ks, KS_MAR(i)); addr[i] = reg >> 8; addr[i + 1] = reg & 0xff; } eth_hw_addr_set(dev, addr); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); } /** * ks8851_init_mac - initialise the mac address * @ks: The device structure @@ -326,15 +322,14 @@ static void ks8851_rx_pkts(struct ks8851_net *ks, struct sk_buff_head *rxq) */ static irqreturn_t ks8851_irq(int irq, void *_ks) { struct ks8851_net *ks = _ks; struct sk_buff_head rxq; - unsigned long flags; unsigned int status; struct sk_buff *skb; - ks8851_lock(ks, &flags); + ks8851_lock(ks); status = ks8851_rdreg16(ks, KS_ISR); ks8851_wrreg16(ks, KS_ISR, status); netif_dbg(ks, intr, ks->netdev, @@ -387,11 +382,11 @@ static irqreturn_t ks8851_irq(int irq, void *_ks) ks8851_wrreg16(ks, KS_RXCR2, rxc->rxcr2); ks8851_wrreg16(ks, KS_RXCR1, rxc->rxcr1); } - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); if (status & IRQ_LCI) mii_check_link(&ks->mii); if (status & IRQ_RXI) @@ -419,11 +414,10 @@ static void ks8851_flush_tx_work(struct ks8851_net *ks) * 'ifconfig up' on the device. */ static int ks8851_net_open(struct net_device *dev) { struct ks8851_net *ks = netdev_priv(dev); - unsigned long flags; int ret; ret = request_threaded_irq(dev->irq, NULL, ks8851_irq, IRQF_TRIGGER_LOW | IRQF_ONESHOT, dev->name, ks); @@ -432,11 +426,11 @@ static int ks8851_net_open(struct net_device *dev) return ret; } /* lock the card, even if we may not actually be doing anything * else at the moment */ - ks8851_lock(ks, &flags); + ks8851_lock(ks); netif_dbg(ks, ifup, ks->netdev, "opening\n"); /* bring chip out of any power saving mode it was in */ ks8851_set_powermode(ks, PMECR_PM_NORMAL); @@ -485,11 +479,11 @@ static int ks8851_net_open(struct net_device *dev) ks->tx_space = ks8851_rdreg16(ks, KS_TXMIR); netif_start_queue(ks->netdev); netif_dbg(ks, ifup, ks->netdev, "network device up\n"); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); mii_check_link(&ks->mii); return 0; } /** @@ -501,36 +495,35 @@ static int ks8851_net_open(struct net_device *dev) * power state whilst it is not being used. */ static int ks8851_net_stop(struct net_device *dev) { struct ks8851_net *ks = netdev_priv(dev); - unsigned long flags; netif_info(ks, ifdown, dev, "shutting down\n"); netif_stop_queue(dev); - ks8851_lock(ks, &flags); + ks8851_lock(ks); /* turn off the IRQs and ack any outstanding */ ks8851_wrreg16(ks, KS_IER, 0x0000); ks8851_wrreg16(ks, KS_ISR, 0xffff); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); /* stop any outstanding work */ ks8851_flush_tx_work(ks); flush_work(&ks->rxctrl_work); - ks8851_lock(ks, &flags); + ks8851_lock(ks); /* shutdown RX process */ ks8851_wrreg16(ks, KS_RXCR1, 0x0000); /* shutdown TX process */ ks8851_wrreg16(ks, KS_TXCR, 0x0000); /* set powermode to soft power down to save power */ ks8851_set_powermode(ks, PMECR_PM_SOFTDOWN); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); /* ensure any queued tx buffers are dumped */ while (!skb_queue_empty(&ks->txq)) { struct sk_buff *txb = skb_dequeue(&ks->txq); @@ -580,18 +573,17 @@ static netdev_tx_t ks8851_start_xmit(struct sk_buff *skb, * complete. The interrupt handler then writes the new values into the chip. */ static void ks8851_rxctrl_work(struct work_struct *work) { struct ks8851_net *ks = container_of(work, struct ks8851_net, rxctrl_work); - unsigned long flags; - ks8851_lock(ks, &flags); + ks8851_lock(ks); /* need to shutdown RXQ before modifying filter parameters */ ks8851_wrreg16(ks, KS_RXCR1, 0x00); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); } static void ks8851_set_rx_mode(struct net_device *dev) { struct ks8851_net *ks = netdev_priv(dev); @@ -794,11 +786,10 @@ static void ks8851_eeprom_release(struct ks8851_net *ks) static int ks8851_set_eeprom(struct net_device *dev, struct ethtool_eeprom *ee, u8 *data) { struct ks8851_net *ks = netdev_priv(dev); int offset = ee->offset; - unsigned long flags; int len = ee->len; u16 tmp; /* currently only support byte writing */ if (len != 1) @@ -808,11 +799,11 @@ static int ks8851_set_eeprom(struct net_device *dev, return -EINVAL; if (!(ks->rc_ccr & CCR_EEPROM)) return -ENOENT; - ks8851_lock(ks, &flags); + ks8851_lock(ks); ks8851_eeprom_claim(ks); eeprom_93cx6_wren(&ks->eeprom, true); @@ -831,39 +822,38 @@ static int ks8851_set_eeprom(struct net_device *dev, eeprom_93cx6_write(&ks->eeprom, offset/2, tmp); eeprom_93cx6_wren(&ks->eeprom, false); ks8851_eeprom_release(ks); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); return 0; } static int ks8851_get_eeprom(struct net_device *dev, struct ethtool_eeprom *ee, u8 *data) { struct ks8851_net *ks = netdev_priv(dev); int offset = ee->offset; - unsigned long flags; int len = ee->len; /* must be 2 byte aligned */ if (len & 1 || offset & 1) return -EINVAL; if (!(ks->rc_ccr & CCR_EEPROM)) return -ENOENT; - ks8851_lock(ks, &flags); + ks8851_lock(ks); ks8851_eeprom_claim(ks); ee->magic = KS_EEPROM_MAGIC; eeprom_93cx6_multiread(&ks->eeprom, offset/2, (__le16 *)data, len/2); ks8851_eeprom_release(ks); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); return 0; } static int ks8851_get_eeprom_len(struct net_device *dev) @@ -918,21 +908,20 @@ static int ks8851_phy_reg(int reg) } static int ks8851_phy_read_common(struct net_device *dev, int phy_addr, int reg) { struct ks8851_net *ks = netdev_priv(dev); - unsigned long flags; int result; int ksreg; ksreg = ks8851_phy_reg(reg); if (ksreg < 0) return ksreg; - ks8851_lock(ks, &flags); + ks8851_lock(ks); result = ks8851_rdreg16(ks, ksreg); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); return result; } /** @@ -963,18 +952,17 @@ static int ks8851_phy_read(struct net_device *dev, int phy_addr, int reg) static void ks8851_phy_write(struct net_device *dev, int phy, int reg, int value) { struct ks8851_net *ks = netdev_priv(dev); - unsigned long flags; int ksreg; ksreg = ks8851_phy_reg(reg); if (ksreg >= 0) { - ks8851_lock(ks, &flags); + ks8851_lock(ks); ks8851_wrreg16(ks, ksreg, value); - ks8851_unlock(ks, &flags); + ks8851_unlock(ks); } } static int ks8851_mdio_read(struct mii_bus *bus, int phy_id, int reg) { diff --git a/drivers/net/ethernet/micrel/ks8851_par.c b/drivers/net/ethernet/micrel/ks8851_par.c index 96fb0ffcedb9..7f16ee5a91e2 100644 --- a/drivers/net/ethernet/micrel/ks8851_par.c +++ b/drivers/net/ethernet/micrel/ks8851_par.c @@ -53,33 +53,31 @@ struct ks8851_net_par { #define to_ks8851_par(ks) container_of((ks), struct ks8851_net_par, ks8851) /** * ks8851_lock_par - register access lock * @ks: The chip state - * @flags: Spinlock flags * * Claim chip register access lock */ -static void ks8851_lock_par(struct ks8851_net *ks, unsigned long *flags) +static void ks8851_lock_par(struct ks8851_net *ks) { struct ks8851_net_par *ksp = to_ks8851_par(ks); - spin_lock_irqsave(&ksp->lock, *flags); + spin_lock_bh(&ksp->lock); } /** * ks8851_unlock_par - register access unlock * @ks: The chip state - * @flags: Spinlock flags * * Release chip register access lock */ -static void ks8851_unlock_par(struct ks8851_net *ks, unsigned long *flags) +static void ks8851_unlock_par(struct ks8851_net *ks) { struct ks8851_net_par *ksp = to_ks8851_par(ks); - spin_unlock_irqrestore(&ksp->lock, *flags); + spin_unlock_bh(&ksp->lock); } /** * ks_check_endian - Check whether endianness of the bus is correct * @ks : The chip information @@ -231,19 +229,18 @@ static unsigned int ks8851_rdreg16_par_txqcr(struct ks8851_net *ks) static netdev_tx_t ks8851_start_xmit_par(struct sk_buff *skb, struct net_device *dev) { struct ks8851_net *ks = netdev_priv(dev); netdev_tx_t ret = NETDEV_TX_OK; - unsigned long flags; unsigned int txqcr; u16 txmir; int err; netif_dbg(ks, tx_queued, ks->netdev, "%s: skb %p, %d@%p\n", __func__, skb, skb->len, skb->data); - ks8851_lock_par(ks, &flags); + ks8851_lock_par(ks); txmir = ks8851_rdreg16_par(ks, KS_TXMIR) & 0x1fff; if (likely(txmir >= skb->len + 12)) { ks8851_wrreg16_par(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_SDA); @@ -260,11 +257,11 @@ static netdev_tx_t ks8851_start_xmit_par(struct sk_buff *skb, ks8851_done_tx(ks, skb); } else { ret = NETDEV_TX_BUSY; } - ks8851_unlock_par(ks, &flags); + ks8851_unlock_par(ks); return ret; } static int ks8851_probe_par(struct platform_device *pdev) diff --git a/drivers/net/ethernet/micrel/ks8851_spi.c b/drivers/net/ethernet/micrel/ks8851_spi.c index e33a5e7beb39..50afe8c11178 100644 --- a/drivers/net/ethernet/micrel/ks8851_spi.c +++ b/drivers/net/ethernet/micrel/ks8851_spi.c @@ -71,29 +71,27 @@ struct ks8851_net_spi { (BYTE_EN(_byteen) | (_reg) << (8 + 2) | (_reg) >> 6) /** * ks8851_lock_spi - register access lock * @ks: The chip state - * @flags: Spinlock flags * * Claim chip register access lock */ -static void ks8851_lock_spi(struct ks8851_net *ks, unsigned long *flags) +static void ks8851_lock_spi(struct ks8851_net *ks) { struct ks8851_net_spi *kss = to_ks8851_spi(ks); mutex_lock(&kss->lock); } /** * ks8851_unlock_spi - register access unlock * @ks: The chip state - * @flags: Spinlock flags * * Release chip register access lock */ -static void ks8851_unlock_spi(struct ks8851_net *ks, unsigned long *flags) +static void ks8851_unlock_spi(struct ks8851_net *ks) { struct ks8851_net_spi *kss = to_ks8851_spi(ks); mutex_unlock(&kss->lock); } @@ -309,19 +307,18 @@ static void ks8851_tx_work(struct work_struct *work) { unsigned int dequeued_len = 0; struct ks8851_net_spi *kss; unsigned short tx_space; struct ks8851_net *ks; - unsigned long flags; struct sk_buff *txb; bool last; kss = container_of(work, struct ks8851_net_spi, tx_work); ks = &kss->ks8851; last = skb_queue_empty(&ks->txq); - ks8851_lock_spi(ks, &flags); + ks8851_lock_spi(ks); while (!last) { txb = skb_dequeue(&ks->txq); last = skb_queue_empty(&ks->txq); @@ -343,11 +340,11 @@ static void ks8851_tx_work(struct work_struct *work) spin_lock_bh(&ks->statelock); ks->queued_len -= dequeued_len; ks->tx_space = tx_space; spin_unlock_bh(&ks->statelock); - ks8851_unlock_spi(ks, &flags); + ks8851_unlock_spi(ks); } /** * ks8851_flush_tx_work_spi - flush outstanding TX work * @ks: The device state -- 2.43.0