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

e18aca02 · Linus Torvalds <[email protected]> · 2017-07-01 09:10:17 -07:00

Pull x86 fixes from Thomas Gleixner:
 "Fixlets for x86:

   - Prevent kexec crash when KASLR is enabled, which was caused by an
     address calculation bug

   - Restore the freeing of PUDs on memory hot remove

   - Correct a negated pointer check in the intel uncore performance
     monitoring driver

   - Plug a memory leak in an error exit path in the RDT code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel_rdt: Fix memory leak on mount failure
  x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug
  x86/boot/KASLR: Add checking for the offset of kernel virtual address randomization
  perf/x86/intel/uncore: Fix wrong box pointer check
  x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD

Commit: e18aca0236a2dac4a134ace4685e97ad09d3605b
Parents: a527bf61 · 79298acc

Merge commit. Changes below are compared with the first parent: a527bf61.

Changes

6 files changed · +15 −10

File	Status	Add	Del	Content
arch/x86/boot/compressed/kaslr.c	modified	+0	−3	View file
arch/x86/boot/compressed/misc.c	modified	+4	−2	View file
arch/x86/boot/compressed/misc.h	modified	+0	−2	View file
arch/x86/events/intel/uncore.c	modified	+1	−1	View file
arch/x86/kernel/cpu/intel_rdt_rdtgroup.c	modified	+3	−1	View file
arch/x86/mm/init_64.c	modified	+7	−1	View file

arch/x86/boot/compressed/kaslr.c

View file

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 54c24f0..56a7e92 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -564,9 +564,6 @@ void choose_random_location(unsigned long input,
 {
 	unsigned long random_addr, min_addr;
 
-	/* By default, keep output position unchanged. */
-	*virt_addr = *output;
-
 	if (cmdline_find_option_bool("nokaslr")) {
 		warn("KASLR disabled: 'nokaslr' on cmdline.");
 		return;

arch/x86/boot/compressed/misc.c

View file

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index b3c5a5f..00241c8 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -338,7 +338,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
 				  unsigned long output_len)
 {
 	const unsigned long kernel_total_size = VO__end - VO__text;
-	unsigned long virt_addr = (unsigned long)output;
+	unsigned long virt_addr = LOAD_PHYSICAL_ADDR;
 
 	/* Retain x86 boot parameters pointer passed from startup_32/64. */
 	boot_params = rmode;
@@ -390,6 +390,8 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
 #ifdef CONFIG_X86_64
 	if (heap > 0x3fffffffffffUL)
 		error("Destination address too large");
+	if (virt_addr + max(output_len, kernel_total_size) > KERNEL_IMAGE_SIZE)
+		error("Destination virtual address is beyond the kernel mapping area");
 #else
 	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
 		error("Destination address too large");
@@ -397,7 +399,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
 #ifndef CONFIG_RELOCATABLE
 	if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
 		error("Destination address does not match LOAD_PHYSICAL_ADDR");
-	if ((unsigned long)output != virt_addr)
+	if (virt_addr != LOAD_PHYSICAL_ADDR)
 		error("Destination virtual address changed when not relocatable");
 #endif
 

arch/x86/boot/compressed/misc.h

View file

diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 1c8355e..766a521 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -81,8 +81,6 @@ static inline void choose_random_location(unsigned long input,
 					  unsigned long output_size,
 					  unsigned long *virt_addr)
 {
-	/* No change from existing output location. */
-	*virt_addr = *output;
 }
 #endif
 

arch/x86/events/intel/uncore.c

View file

diff --git a/arch/x86/events/intel/uncore.c b/arch/x86/events/intel/uncore.c
index 758c1aa..44ec523 100644
--- a/arch/x86/events/intel/uncore.c
+++ b/arch/x86/events/intel/uncore.c
@@ -1170,7 +1170,7 @@ static int uncore_event_cpu_online(unsigned int cpu)
 		pmu = type->pmus;
 		for (i = 0; i < type->num_boxes; i++, pmu++) {
 			box = pmu->boxes[pkg];
-			if (!box && atomic_inc_return(&box->refcnt) == 1)
+			if (box && atomic_inc_return(&box->refcnt) == 1)
 				uncore_box_init(box);
 		}
 	}

arch/x86/kernel/cpu/intel_rdt_rdtgroup.c

View file

diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index f5af0cc..9257bd9 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -856,11 +856,13 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type,
 	dentry = kernfs_mount(fs_type, flags, rdt_root,
 			      RDTGROUP_SUPER_MAGIC, NULL);
 	if (IS_ERR(dentry))
-		goto out_cdp;
+		goto out_destroy;
 
 	static_branch_enable(&rdt_enable_key);
 	goto out;
 
+out_destroy:
+	kernfs_remove(kn_info);
 out_cdp:
 	cdp_disable();
 out:

arch/x86/mm/init_64.c

View file

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 95651dc..0a59daf 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -990,7 +990,13 @@ remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
 
 		pud_base = pud_offset(p4d, 0);
 		remove_pud_table(pud_base, addr, next, direct);
-		free_pud_table(pud_base, p4d);
+		/*
+		 * For 4-level page tables we do not want to free PUDs, but in the
+		 * 5-level case we should free them. This code will have to change
+		 * to adapt for boot-time switching between 4 and 5 level page tables.
+		 */
+		if (CONFIG_PGTABLE_LEVELS == 5)
+			free_pud_table(pud_base, p4d);
 	}
 
 	if (direct)