From 593ee20766921fec643194dff829e17f30552220 Mon Sep 17 00:00:00 2001 From: Kristen Accardi Date: Sat, 20 May 2006 15:00:08 -0700 Subject: [PATCH] pci: correctly allocate return buffers for osc calls The OSC set and query functions do not allocate enough space for return values, and set the output buffer length to a false, too large value. This causes the acpi-ca code to assume that the output buffer is larger than it actually is, and overwrite memory when copying acpi return buffers into this caller provided buffer. In some cases this can cause kernel oops if the memory that is overwritten is a pointer. This patch will change these calls to use a dynamically allocated output buffer, thus allowing the acpi-ca code to decide how much space is needed. Signed-off-by: Kristen Carlson Accardi Cc: "Brown, Len" Cc: "Yu, Luming" Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/pci/pci-acpi.c | 60 +++++++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 25 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 6917c6cb091287..c2ecae5ff0c176 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -33,13 +33,10 @@ acpi_query_osc ( acpi_status status; struct acpi_object_list input; union acpi_object in_params[4]; - struct acpi_buffer output; - union acpi_object out_obj; + struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL}; + union acpi_object *out_obj; u32 osc_dw0; - /* Setting up output buffer */ - output.length = sizeof(out_obj) + 3*sizeof(u32); - output.pointer = &out_obj; /* Setting up input parameters */ input.count = 4; @@ -61,12 +58,15 @@ acpi_query_osc ( "Evaluate _OSC Set fails. Status = 0x%04x\n", status); return status; } - if (out_obj.type != ACPI_TYPE_BUFFER) { + out_obj = output.pointer; + + if (out_obj->type != ACPI_TYPE_BUFFER) { printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n"); - return AE_TYPE; + status = AE_TYPE; + goto query_osc_out; } - osc_dw0 = *((u32 *) out_obj.buffer.pointer); + osc_dw0 = *((u32 *) out_obj->buffer.pointer); if (osc_dw0) { if (osc_dw0 & OSC_REQUEST_ERROR) printk(KERN_DEBUG "_OSC request fails\n"); @@ -76,15 +76,21 @@ acpi_query_osc ( printk(KERN_DEBUG "_OSC invalid revision\n"); if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) { /* Update Global Control Set */ - global_ctrlsets = *((u32 *)(out_obj.buffer.pointer+8)); - return AE_OK; + global_ctrlsets = *((u32 *)(out_obj->buffer.pointer+8)); + status = AE_OK; + goto query_osc_out; } - return AE_ERROR; + status = AE_ERROR; + goto query_osc_out; } /* Update Global Control Set */ - global_ctrlsets = *((u32 *)(out_obj.buffer.pointer + 8)); - return AE_OK; + global_ctrlsets = *((u32 *)(out_obj->buffer.pointer + 8)); + status = AE_OK; + +query_osc_out: + kfree(output.pointer); + return status; } @@ -96,14 +102,10 @@ acpi_run_osc ( acpi_status status; struct acpi_object_list input; union acpi_object in_params[4]; - struct acpi_buffer output; - union acpi_object out_obj; + struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL}; + union acpi_object *out_obj; u32 osc_dw0; - /* Setting up output buffer */ - output.length = sizeof(out_obj) + 3*sizeof(u32); - output.pointer = &out_obj; - /* Setting up input parameters */ input.count = 4; input.pointer = in_params; @@ -124,12 +126,14 @@ acpi_run_osc ( "Evaluate _OSC Set fails. Status = 0x%04x\n", status); return status; } - if (out_obj.type != ACPI_TYPE_BUFFER) { + out_obj = output.pointer; + if (out_obj->type != ACPI_TYPE_BUFFER) { printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n"); - return AE_TYPE; + status = AE_TYPE; + goto run_osc_out; } - osc_dw0 = *((u32 *) out_obj.buffer.pointer); + osc_dw0 = *((u32 *) out_obj->buffer.pointer); if (osc_dw0) { if (osc_dw0 & OSC_REQUEST_ERROR) printk(KERN_DEBUG "_OSC request fails\n"); @@ -139,11 +143,17 @@ acpi_run_osc ( printk(KERN_DEBUG "_OSC invalid revision\n"); if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) { printk(KERN_DEBUG "_OSC FW not grant req. control\n"); - return AE_SUPPORT; + status = AE_SUPPORT; + goto run_osc_out; } - return AE_ERROR; + status = AE_ERROR; + goto run_osc_out; } - return AE_OK; + status = AE_OK; + +run_osc_out: + kfree(output.pointer); + return status; } /** -- cgit 1.2.3-korg