Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Ingo writes:
  "x86 fixes

   An intel_rdt memory access fix and a VLA fix in pgd_alloc()."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Avoid VLA in pgd_alloc()
  x86/intel_rdt: Fix out-of-bounds memory access in CBM tests
This commit is contained in:
Greg Kroah-Hartman 2018-10-11 12:28:23 +02:00
commit 9f203e2f2f
4 changed files with 45 additions and 27 deletions

View File

@ -529,14 +529,14 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
int rdtgroup_schemata_show(struct kernfs_open_file *of,
struct seq_file *s, void *v);
bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
u32 _cbm, int closid, bool exclusive);
unsigned long cbm, int closid, bool exclusive);
unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_domain *d,
u32 cbm);
unsigned long cbm);
enum rdtgrp_mode rdtgroup_mode_by_closid(int closid);
int rdtgroup_tasks_assigned(struct rdtgroup *r);
int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp);
bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, u32 _cbm);
bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, unsigned long cbm);
bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d);
int rdt_pseudo_lock_init(void);
void rdt_pseudo_lock_release(void);

View File

@ -797,25 +797,27 @@ int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp)
/**
* rdtgroup_cbm_overlaps_pseudo_locked - Test if CBM or portion is pseudo-locked
* @d: RDT domain
* @_cbm: CBM to test
* @cbm: CBM to test
*
* @d represents a cache instance and @_cbm a capacity bitmask that is
* considered for it. Determine if @_cbm overlaps with any existing
* @d represents a cache instance and @cbm a capacity bitmask that is
* considered for it. Determine if @cbm overlaps with any existing
* pseudo-locked region on @d.
*
* Return: true if @_cbm overlaps with pseudo-locked region on @d, false
* @cbm is unsigned long, even if only 32 bits are used, to make the
* bitmap functions work correctly.
*
* Return: true if @cbm overlaps with pseudo-locked region on @d, false
* otherwise.
*/
bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, u32 _cbm)
bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, unsigned long cbm)
{
unsigned long *cbm = (unsigned long *)&_cbm;
unsigned long *cbm_b;
unsigned int cbm_len;
unsigned long cbm_b;
if (d->plr) {
cbm_len = d->plr->r->cache.cbm_len;
cbm_b = (unsigned long *)&d->plr->cbm;
if (bitmap_intersects(cbm, cbm_b, cbm_len))
cbm_b = d->plr->cbm;
if (bitmap_intersects(&cbm, &cbm_b, cbm_len))
return true;
}
return false;

View File

@ -975,33 +975,34 @@ static int rdtgroup_mode_show(struct kernfs_open_file *of,
* is false then overlaps with any resource group or hardware entities
* will be considered.
*
* @cbm is unsigned long, even if only 32 bits are used, to make the
* bitmap functions work correctly.
*
* Return: false if CBM does not overlap, true if it does.
*/
bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
u32 _cbm, int closid, bool exclusive)
unsigned long cbm, int closid, bool exclusive)
{
unsigned long *cbm = (unsigned long *)&_cbm;
unsigned long *ctrl_b;
enum rdtgrp_mode mode;
unsigned long ctrl_b;
u32 *ctrl;
int i;
/* Check for any overlap with regions used by hardware directly */
if (!exclusive) {
if (bitmap_intersects(cbm,
(unsigned long *)&r->cache.shareable_bits,
r->cache.cbm_len))
ctrl_b = r->cache.shareable_bits;
if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len))
return true;
}
/* Check for overlap with other resource groups */
ctrl = d->ctrl_val;
for (i = 0; i < closids_supported(); i++, ctrl++) {
ctrl_b = (unsigned long *)ctrl;
ctrl_b = *ctrl;
mode = rdtgroup_mode_by_closid(i);
if (closid_allocated(i) && i != closid &&
mode != RDT_MODE_PSEUDO_LOCKSETUP) {
if (bitmap_intersects(cbm, ctrl_b, r->cache.cbm_len)) {
if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len)) {
if (exclusive) {
if (mode == RDT_MODE_EXCLUSIVE)
return true;
@ -1138,15 +1139,18 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
* computed by first dividing the total cache size by the CBM length to
* determine how many bytes each bit in the bitmask represents. The result
* is multiplied with the number of bits set in the bitmask.
*
* @cbm is unsigned long, even if only 32 bits are used to make the
* bitmap functions work correctly.
*/
unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
struct rdt_domain *d, u32 cbm)
struct rdt_domain *d, unsigned long cbm)
{
struct cpu_cacheinfo *ci;
unsigned int size = 0;
int num_b, i;
num_b = bitmap_weight((unsigned long *)&cbm, r->cache.cbm_len);
num_b = bitmap_weight(&cbm, r->cache.cbm_len);
ci = get_cpu_cacheinfo(cpumask_any(&d->cpu_mask));
for (i = 0; i < ci->num_leaves; i++) {
if (ci->info_list[i].level == r->cache_level) {
@ -2353,6 +2357,7 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
u32 used_b = 0, unused_b = 0;
u32 closid = rdtgrp->closid;
struct rdt_resource *r;
unsigned long tmp_cbm;
enum rdtgrp_mode mode;
struct rdt_domain *d;
int i, ret;
@ -2390,9 +2395,14 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
* modify the CBM based on system availability.
*/
cbm_ensure_valid(&d->new_ctrl, r);
if (bitmap_weight((unsigned long *) &d->new_ctrl,
r->cache.cbm_len) <
r->cache.min_cbm_bits) {
/*
* Assign the u32 CBM to an unsigned long to ensure
* that bitmap_weight() does not access out-of-bound
* memory.
*/
tmp_cbm = d->new_ctrl;
if (bitmap_weight(&tmp_cbm, r->cache.cbm_len) <
r->cache.min_cbm_bits) {
rdt_last_cmd_printf("no space on %s:%d\n",
r->name, d->id);
return -ENOSPC;

View File

@ -115,6 +115,8 @@ static inline void pgd_list_del(pgd_t *pgd)
#define UNSHARED_PTRS_PER_PGD \
(SHARED_KERNEL_PMD ? KERNEL_PGD_BOUNDARY : PTRS_PER_PGD)
#define MAX_UNSHARED_PTRS_PER_PGD \
max_t(size_t, KERNEL_PGD_BOUNDARY, PTRS_PER_PGD)
static void pgd_set_mm(pgd_t *pgd, struct mm_struct *mm)
@ -181,6 +183,7 @@ static void pgd_dtor(pgd_t *pgd)
* and initialize the kernel pmds here.
*/
#define PREALLOCATED_PMDS UNSHARED_PTRS_PER_PGD
#define MAX_PREALLOCATED_PMDS MAX_UNSHARED_PTRS_PER_PGD
/*
* We allocate separate PMDs for the kernel part of the user page-table
@ -189,6 +192,7 @@ static void pgd_dtor(pgd_t *pgd)
*/
#define PREALLOCATED_USER_PMDS (static_cpu_has(X86_FEATURE_PTI) ? \
KERNEL_PGD_PTRS : 0)
#define MAX_PREALLOCATED_USER_PMDS KERNEL_PGD_PTRS
void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
{
@ -210,7 +214,9 @@ void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
/* No need to prepopulate any pagetable entries in non-PAE modes. */
#define PREALLOCATED_PMDS 0
#define MAX_PREALLOCATED_PMDS 0
#define PREALLOCATED_USER_PMDS 0
#define MAX_PREALLOCATED_USER_PMDS 0
#endif /* CONFIG_X86_PAE */
static void free_pmds(struct mm_struct *mm, pmd_t *pmds[], int count)
@ -428,8 +434,8 @@ static inline void _pgd_free(pgd_t *pgd)
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd;
pmd_t *u_pmds[PREALLOCATED_USER_PMDS];
pmd_t *pmds[PREALLOCATED_PMDS];
pmd_t *u_pmds[MAX_PREALLOCATED_USER_PMDS];
pmd_t *pmds[MAX_PREALLOCATED_PMDS];
pgd = _pgd_alloc();