maillist inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9678 Reference: https://lore.kernel.org/all/20260727025645.2600363-1-pulehui@huaweicloud.com -------------------------------- Syzkaller reported a kernel panic caused by an out-of-bounds MMIO access in the e1000e driver. [ 82.868719][ T404] e1000e 0000:00:02.0: The NVM Checksum Is Not Valid [ 82.872328][ T404] Unable to handle kernel paging request at virtual address ffff80008894e090 [ 83.085218][ T404] CPU: 2 UID: 0 PID: 404 Comm: bash Not tainted 7.2.0-rc2-g3f1f75536668 #1 PREEMPTLAZY [ 83.129013][ T404] pc : e1000_get_cfg_done_82571+0x70/0x158 [ 83.140092][ T404] lr : e1000_get_cfg_done_82571+0x68/0x158 [ 83.151196][ T404] sp : ffff80008ac37410 [ 83.158922][ T404] x29: ffff80008ac37410 x28: ffff0000cd6a11b8 x27: ffff0000c58190d0 [ 83.173919][ T404] x26: ffff0000cd6a11b8 x25: ffff0000cd6a0bc0 x24: ffff0000cd6a0000 [ 83.189417][ T404] x23: 0000000000001010 x22: ffff0000cd6a11c0 x21: ffff0000cd6a11b8 [ 83.205195][ T404] x20: 0000000000000064 x19: ffff80008894e090 x18: 0000000000000000 [ 83.220545][ T404] x17: ffff800081c1a3f4 x16: ffff800081c19c10 x15: ffff800081e86510 [ 83.235764][ T404] x14: 0000000000000001 x13: 0000000000000001 x12: ffff60001bc8a8b3 [ 83.251301][ T404] x11: 1fffe0001bc8a8b2 x10: ffff60001bc8a8b2 x9 : ffff800081eae25c [ 83.266705][ T404] x8 : 00009fffe437574e x7 : ffff0000de454593 x6 : 0000000000000001 [ 83.281919][ T404] x5 : ffff0000cf2b9640 x4 : 0000000000000000 x3 : dfff800000000000 [ 83.297317][ T404] x2 : 0000000000000007 x1 : ffff0000cd6a11c0 x0 : 0000000000000000 [ 83.312601][ T404] Call trace: [ 83.318662][ T404] e1000_get_cfg_done_82571+0x70/0x158 (P) [ 83.329748][ T404] e1000e_phy_hw_reset_generic+0x17c/0x1a8 [ 83.341541][ T404] e1000_probe+0xbd8/0x1988 [ 83.350334][ T404] local_pci_probe+0x84/0x130 Repetition steps: 1. Find PCI device which BAR0 size <= 4K. If it's: Device Addr: 0000:00:02.0 BAR0 SIZE: 4K Vendor/Device ID: 0x1af4 0x1004 2. Unbind the above PCI device echo '0000:00:02.0' > /sys/bus/pci/devices/0000:00:02.0/driver/unbind 3. Set the above device to e1000e new_id echo '1af4 1004' > /sys/bus/pci/drivers/e1000e/new_id During e1000_probe(), the driver maps the device's BAR0 memory region. If the device has a 4K BAR0, ioremap() maps only 4K of space. Later in the probe process, when the NVM checksum validation fails, the driver attempts to perform a hardware reset and falls back to the err_eeprom cleanup path. This cleanup path will trigger an OOB access kernel panic: e1000_phy_hw_reset e1000e_phy_hw_reset_generic e1000_get_cfg_done_82571 er32(EEMNGCTL) readl(hw->hw_addr + EEMNGCTL); <-- EEMNGCTL(0x1010) > 4K, OOB access Fix this by verifying that the MMIO length (pci_resource_len(pdev, 0)) is at least SZ_64K before calling ioremap(). This accounts not only for standard registers up to E1000_SYSSTMPH, but also for flash registers mapped on ICH/PCH chipsets (up to offset 0xE074 / ~57.1 KB). Since PCI BAR sizes are power-of-two aligned, SZ_64K is the minimum valid BAR0 size required to ensure all subsequent MMIO accesses remain strictly within the mapped boundary. Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)") Reviewed-by: Breno Leitao <leitao@debian.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> --- drivers/net/ethernet/intel/e1000e/netdev.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 9e383ce1008e..86a88fe8401d 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -7377,6 +7377,12 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent) mmio_len = pci_resource_len(pdev, 0); err = -EIO; + /* Smallest BAR0 that covers every register the driver accesses */ + if (mmio_len < SZ_64K) { + dev_err(&pdev->dev, "MMIO len is too small\n"); + goto err_ioremap; + } + adapter->hw.hw_addr = ioremap(mmio_start, mmio_len); if (!adapter->hw.hw_addr) goto err_ioremap; -- 2.34.1