'pds' does not perform 4-byte alignment check. If 'pds' is not 4-byte aligned, it will cause alignment fault. Mem abort info: ESR = 0x0000000096000021 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x21: alignment fault Data abort info: ISV = 0, ISS = 0x00000021, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000203ef6a0d000 [ffff8000c930ffff] pgd=1000002080bcf003, p4d=1000002080bcf003, pud=100000403ae8a003, pmd=1000202027498003, pte=00680000b000ff13 Internal error: Oops: 0000000096000021 [#1] SMP CPU: 16 PID: 451316 Comm: read_all Kdump: loaded Tainted: G W 6.6.0+ #6 Hardware name: Huawei TaiShan 200 (Model 2280)/BC82AMDD, BIOS 6.57 05/17/2023 pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : pci_get_rom_size+0x74/0x1f0 lr : pci_map_rom+0x140/0x280 sp : ffff8000b96178f0 x29: ffff8000b96178f0 x28: ffff004e284b3f80 x27: ffff8000b9617be8 x26: ffff0020facb7020 x25: 0000000000100000 x24: 00000000b0000000 x23: ffff00208c8ea740 x22: 1ffff000172c2f2e x21: ffff8000c9300000 x20: 0000000000100000 x19: ffff8000c9300000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000041b58ab3 x12: 1ffff000172c2ec8 x11: 00000000f1f1f1f1 x10: ffff7000172c2ec8 x9 : ffffb9ba9db93ad8 x8 : ffff7000172c2eac x7 : ffff8000c9400000 x6 : 0000000052494350 x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff8000c930ffff x2 : 000000000000aa55 x1 : 0000000000000000 x0 : ffff00208c8ea000 Call trace: pci_get_rom_size+0x74/0x1f0 pci_map_rom+0x140/0x280 pci_read_rom+0xa8/0x158 sysfs_kf_bin_read+0xb8/0x130 kernfs_file_read_iter+0x124/0x278 kernfs_fop_read_iter+0x6c/0xa8 new_sync_read+0x128/0x208 Inject: max_dir_depth vfs_read+0x244/0x2b0 ksys_read+0xd0/0x188 __arm64_sys_read+0x4c/0x68 invoke_syscall+0x68/0x1a0 el0_svc_common.constprop.0+0x11c/0x150 do_el0_svc+0x38/0x50 el0_svc+0x64/0x258 el0t_64_sync_handler+0x100/0x130 el0t_64_sync+0x188/0x190 Code: d50331bf ca030061 b5000001 8b030263 (b9400064) SMP: stopping secondary CPUs Starting crashdump kernel... In UEFI Specification Version 2.8, describes that the PCIR data structure must start on a 4-byte boundary. Fix it by verifying the 'pds' is aligned. Cc: stable@xxxxxxxxxxxxxxx Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: liwei <liwei728@xxxxxxxxxx> --- drivers/pci/rom.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c index e18d3a4383ba..0fa6b3da63cc 100644 --- a/drivers/pci/rom.c +++ b/drivers/pci/rom.c @@ -98,6 +98,12 @@ static size_t pci_get_rom_size(struct pci_dev *pdev, void __iomem *rom, } /* get the PCI data structure and check its "PCIR" signature */ pds = image + readw(image + 24); + /* The PCIR data structure must begin on a 4-byte boundary */ + if (!IS_ALIGNED((unsigned long)pds, 4)) { + pci_info(pdev, "Invalid PCI ROM header signature: PCIR %#06x\n", + readw(image + 24)); + break; + } if (readl(pds) != 0x52494350) { pci_info(pdev, "Invalid PCI ROM data signature: expecting 0x52494350, got %#010x\n", readl(pds)); -- 2.25.1