bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 72 insertions, 0 deletions

diff --git a/drivers/gpib/include/plx9050.h b/drivers/gpib/include/plx9050.h
new file mode 100644
index 000000000..c911b285a
--- /dev/null
+++ b/drivers/gpib/include/plx9050.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/***************************************************************************
+ *  Header for plx9050 pci chip
+ *    copyright            : (C) 2002 by Frank Mori Hess
+ ***************************************************************************/
+
+#ifndef _PLX9050_GPIB_H
+#define _PLX9050_GPIB_H
+
+// plx pci chip registers and bits
+enum {
+	PLX9050_INTCSR_REG = 0x4c,
+	PLX9050_CNTRL_REG = 0x50
+};
+
+enum plx9050_intcsr_bits {
+	PLX9050_LINTR1_EN_BIT = 0x1,
+	PLX9050_LINTR1_POLARITY_BIT = 0x2,
+	PLX9050_LINTR1_STATUS_BIT = 0x4,
+	PLX9050_LINTR2_EN_BIT = 0x8,
+	PLX9050_LINTR2_POLARITY_BIT = 0x10,
+	PLX9050_LINTR2_STATUS_BIT = 0x20,
+	PLX9050_PCI_INTR_EN_BIT = 0x40,
+	PLX9050_SOFT_INTR_BIT = 0x80,
+	PLX9050_LINTR1_SELECT_ENABLE_BIT = 0x100,	// 9052 extension
+	PLX9050_LINTR2_SELECT_ENABLE_BIT = 0x200,	// 9052 extension
+	PLX9050_LINTR1_EDGE_CLEAR_BIT = 0x400,		// 9052 extension
+	PLX9050_LINTR2_EDGE_CLEAR_BIT = 0x800,		// 9052 extension
+};
+
+enum plx9050_cntrl_bits {
+	PLX9050_WAITO_NOT_USER0_SELECT_BIT = 0x1,
+	PLX9050_USER0_OUTPUT_BIT = 0x2,
+	PLX9050_USER0_DATA_BIT = 0x4,
+	PLX9050_LLOCK_NOT_USER1_SELECT_BIT = 0x8,
+	PLX9050_USER1_OUTPUT_BIT = 0x10,
+	PLX9050_USER1_DATA_BIT = 0x20,
+	PLX9050_CS2_NOT_USER2_SELECT_BIT = 0x40,
+	PLX9050_USER2_OUTPUT_BIT = 0x80,
+	PLX9050_USER2_DATA_BIT = 0x100,
+	PLX9050_CS3_NOT_USER3_SELECT_BIT = 0x200,
+	PLX9050_USER3_OUTPUT_BIT = 0x400,
+	PLX9050_USER3_DATA_BIT = 0x800,
+	PLX9050_PCIBAR_ENABLE_MASK = 0x3000,
+	PLX9050_PCIBAR_MEMORY_AND_IO_ENABLE_BITS = 0x0,
+	PLX9050_PCIBAR_MEMORY_NO_IO_ENABLE_BITS = 0x1000,
+	PLX9050_PCIBAR_IO_NO_MEMORY_ENABLE_BITS = 0x2000,
+	PLX9050_PCIBAR_MEMORY_AND_IO_TOO_ENABLE_BITS = 0x3000,
+	PLX9050_PCI_READ_MODE_BIT = 0x4000,
+	PLX9050_PCI_READ_WITH_WRITE_FLUSH_MODE_BIT = 0x8000,
+	PLX9050_PCI_READ_NO_FLUSH_MODE_BIT = 0x10000,
+	PLX9050_PCI_READ_NO_WRITE_MODE_BIT = 0x20000,
+	PLX9050_PCI_WRITE_MODE_BIT = 0x40000,
+	PLX9050_PCI_RETRY_DELAY_MASK = 0x780000,
+	PLX9050_DIRECT_SLAVE_LOCK_ENABLE_BIT = 0x800000,
+	PLX9050_EEPROM_CLOCK_BIT = 0x1000000,
+	PLX9050_EEPROM_CHIP_SELECT_BIT = 0x2000000,
+	PLX9050_WRITE_TO_EEPROM_BIT = 0x4000000,
+	PLX9050_READ_EEPROM_DATA_BIT = 0x8000000,
+	PLX9050_EEPROM_VALID_BIT = 0x10000000,
+	PLX9050_RELOAD_CONFIG_REGISTERS_BIT = 0x20000000,
+	PLX9050_PCI_SOFTWARE_RESET_BIT = 0x40000000,
+	PLX9050_MASK_REVISION_BIT = 0x80000000
+};
+
+static inline unsigned int PLX9050_PCI_RETRY_DELAY_BITS(unsigned int clocks)
+{
+	return ((clocks / 8) << 19) & PLX9050_PCI_RETRY_DELAY_MASK;
+}
+
+#endif	// _PLX9050_GPIB_H