2023-11-23 09:10:20

by Yujie Liu

[permalink] [raw]
Subject: drivers/net/ethernet/3com/3c589_cs.c:581:2: warning: performing pointer arithmetic on a null pointer has undefined behavior

Hi Maciej,

kernel test robot noticed the following build warnings:

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 9b6de136b5f0158c60844f85286a593cb70fb364
commit: 9cc205e3c17d5716da7ebb7fa0c985555e95d009 RISC-V: Make port I/O string accessors actually work
config: riscv-randconfig-r133-20231123 (https://download.01.org/0day-ci/archive/20231123/[email protected]/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
reproduce: (https://download.01.org/0day-ci/archive/20231123/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/r/[email protected]/

All warnings (new ones prefixed by >>):

In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
584 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:743:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
743 | insb(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:104:53: note: expanded from macro 'insb'
104 | #define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c589_cs.c:33:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:751:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
751 | insw(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:105:53: note: expanded from macro 'insw'
105 | #define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c589_cs.c:33:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:759:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
759 | insl(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:106:53: note: expanded from macro 'insl'
106 | #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c589_cs.c:33:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:768:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
768 | outsb(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:118:55: note: expanded from macro 'outsb'
118 | #define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c589_cs.c:33:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:777:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
777 | outsw(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:119:55: note: expanded from macro 'outsw'
119 | #define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c589_cs.c:33:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:786:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
786 | outsl(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:120:55: note: expanded from macro 'outsl'
120 | #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c589_cs.c:33:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:1134:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
1134 | return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
| ~~~~~~~~~~ ^
>> drivers/net/ethernet/3com/3c589_cs.c:581:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
581 | outsl(ioaddr + TX_FIFO, skb->data, (skb->len + 3) >> 2);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:120:55: note: expanded from macro 'outsl'
120 | #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
drivers/net/ethernet/3com/3c589_cs.c:861:5: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
861 | insl(ioaddr+RX_FIFO, skb_put(skb, pkt_len),
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
862 | (pkt_len+3)>>2);
| ~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:106:53: note: expanded from macro 'insl'
106 | #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
15 warnings generated.
--
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
584 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:743:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
743 | insb(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:104:53: note: expanded from macro 'insb'
104 | #define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c574_cs.c:79:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:751:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
751 | insw(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:105:53: note: expanded from macro 'insw'
105 | #define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c574_cs.c:79:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:759:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
759 | insl(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:106:53: note: expanded from macro 'insl'
106 | #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c574_cs.c:79:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:768:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
768 | outsb(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:118:55: note: expanded from macro 'outsb'
118 | #define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c574_cs.c:79:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:777:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
777 | outsw(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:119:55: note: expanded from macro 'outsw'
119 | #define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c574_cs.c:79:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:786:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
786 | outsl(addr, buffer, count);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:120:55: note: expanded from macro 'outsl'
120 | #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
In file included from drivers/net/ethernet/3com/3c574_cs.c:79:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/riscv/include/asm/io.h:136:
include/asm-generic/io.h:1134:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
1134 | return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
| ~~~~~~~~~~ ^
>> drivers/net/ethernet/3com/3c574_cs.c:748:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
748 | outsl(ioaddr + TX_FIFO, skb->data, (skb->len+3)>>2);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:120:55: note: expanded from macro 'outsl'
120 | #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
drivers/net/ethernet/3com/3c574_cs.c:1015:5: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
1015 | insl(ioaddr+RX_FIFO, skb_put(skb, pkt_len),
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1016 | ((pkt_len+3)>>2));
| ~~~~~~~~~~~~~~~~~
arch/riscv/include/asm/io.h:106:53: note: expanded from macro 'insl'
106 | #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
| ~~~~~~~~~~ ^
15 warnings generated.


vim +581 drivers/net/ethernet/3com/3c589_cs.c

^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 562
dbf02fae406daf4 drivers/net/pcmcia/3c589_cs.c Stephen Hemminger 2009-08-31 563 static netdev_tx_t el3_start_xmit(struct sk_buff *skb,
dbf02fae406daf4 drivers/net/pcmcia/3c589_cs.c Stephen Hemminger 2009-08-31 564 struct net_device *dev)
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 565 {
906da809c5be30b drivers/net/pcmcia/3c589_cs.c Olof Johansson 2008-02-04 566 unsigned int ioaddr = dev->base_addr;
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 567 struct el3_private *priv = netdev_priv(dev);
d08d283974f96cb drivers/net/pcmcia/3c589_cs.c Komuro 2006-12-02 568 unsigned long flags;
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 569
f64e96973a1fa88 drivers/net/pcmcia/3c589_cs.c Alexander Kurz 2010-03-31 570 netdev_dbg(dev, "el3_start_xmit(length = %ld) called, status %4.4x.\n",
f64e96973a1fa88 drivers/net/pcmcia/3c589_cs.c Alexander Kurz 2010-03-31 571 (long)skb->len, inw(ioaddr + EL3_STATUS));
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 572
d08d283974f96cb drivers/net/pcmcia/3c589_cs.c Komuro 2006-12-02 573 spin_lock_irqsave(&priv->lock, flags);
d08d283974f96cb drivers/net/pcmcia/3c589_cs.c Komuro 2006-12-02 574
cd65284f6ec4826 drivers/net/pcmcia/3c589_cs.c Paulius Zaleckas 2008-04-30 575 dev->stats.tx_bytes += skb->len;
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 576
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 577 /* Put out the doubleword header... */
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 578 outw(skb->len, ioaddr + TX_FIFO);
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 579 outw(0x00, ioaddr + TX_FIFO);
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 580 /* ... and the packet rounded to a doubleword. */
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 @581 outsl(ioaddr + TX_FIFO, skb->data, (skb->len + 3) >> 2);
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 582
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 583 if (inw(ioaddr + TX_FREE) <= 1536) {
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 584 netif_stop_queue(dev);
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 585 /* Interrupt us when the FIFO has room for max-sized packet. */
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 586 outw(SetTxThreshold + 1536, ioaddr + EL3_CMD);
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 587 }
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 588
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 589 pop_tx_status(dev);
d08d283974f96cb drivers/net/pcmcia/3c589_cs.c Komuro 2006-12-02 590 spin_unlock_irqrestore(&priv->lock, flags);
63ac9b915924d12 drivers/net/pcmcia/3c589_cs.c Patrick McHardy 2007-07-02 591 dev_kfree_skb(skb);
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 592
6ed106549d17474 drivers/net/pcmcia/3c589_cs.c Patrick McHardy 2009-06-23 593 return NETDEV_TX_OK;
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 594 }
^1da177e4c3f415 drivers/net/pcmcia/3c589_cs.c Linus Torvalds 2005-04-16 595

:::::: The code at line 581 was first introduced by commit
:::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2

:::::: TO: Linus Torvalds <[email protected]>
:::::: CC: Linus Torvalds <[email protected]>

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki