+ vmcore-support-mmap-on-proc-vmcore-fix.patch added to -mm tree

[akpm@linux-foundation.org]

Subject: + vmcore-support-mmap-on-proc-vmcore-fix.patch added to -mm tree
To: akpm@linux-foundation.org,d.hatayama@jp.fujitsu.com,kosaki.motohiro@jp.fujitsu.com,kumagai-atsushi@mxc.nes.nec.co.jp,lisa.mitchell@hp.com,vgoyal@redhat.com,zhangyanfei@cn.fujitsu.com
From: akpm@linux-foundation.org
Date: Thu, 23 May 2013 17:20:42 -0700


The patch titled
     Subject: vmcore-support-mmap-on-proc-vmcore-fix
has been added to the -mm tree.  Its filename is
     vmcore-support-mmap-on-proc-vmcore-fix.patch

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------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: vmcore-support-mmap-on-proc-vmcore-fix

use min(), switch to conventional error-unwinding approach

Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lisa Mitchell <lisa.mitchell@hp.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/proc/vmcore.c |   27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff -puN fs/proc/vmcore.c~vmcore-support-mmap-on-proc-vmcore-fix fs/proc/vmcore.c
--- a/fs/proc/vmcore.c~vmcore-support-mmap-on-proc-vmcore-fix
+++ a/fs/proc/vmcore.c
@@ -218,9 +218,7 @@ static int mmap_vmcore(struct file *file
 	if (start < elfcorebuf_sz) {
 		u64 pfn;
 
-		tsz = elfcorebuf_sz - start;
-		if (size < tsz)
-			tsz = size;
+		tsz = min(elfcorebuf_sz - (size_t)start, size);
 		pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT;
 		if (remap_pfn_range(vma, vma->vm_start, pfn, tsz,
 				    vma->vm_page_prot))
@@ -236,15 +234,11 @@ static int mmap_vmcore(struct file *file
 	if (start < elfcorebuf_sz + elfnotes_sz) {
 		void *kaddr;
 
-		tsz = elfcorebuf_sz + elfnotes_sz - start;
-		if (size < tsz)
-			tsz = size;
+		tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size);
 		kaddr = elfnotes_buf + start - elfcorebuf_sz;
 		if (remap_vmalloc_range_partial(vma, vma->vm_start + len,
-						kaddr, tsz)) {
-			do_munmap(vma->vm_mm, vma->vm_start, len);
-			return -EAGAIN;
-		}
+						kaddr, tsz))
+			goto fail;
 		size -= tsz;
 		start += tsz;
 		len += tsz;
@@ -257,16 +251,12 @@ static int mmap_vmcore(struct file *file
 		if (start < m->offset + m->size) {
 			u64 paddr = 0;
 
-			tsz = m->offset + m->size - start;
-			if (size < tsz)
-				tsz = size;
+			tsz = min_t(size_t, m->offset + m->size - start, size);
 			paddr = m->paddr + start - m->offset;
 			if (remap_pfn_range(vma, vma->vm_start + len,
 					    paddr >> PAGE_SHIFT, tsz,
-					    vma->vm_page_prot)) {
-				do_munmap(vma->vm_mm, vma->vm_start, len);
-				return -EAGAIN;
-			}
+					    vma->vm_page_prot))
+				goto fail;
 			size -= tsz;
 			start += tsz;
 			len += tsz;
@@ -277,6 +267,9 @@ static int mmap_vmcore(struct file *file
 	}
 
 	return 0;
+fail:
+	do_munmap(vma->vm_mm, vma->vm_start, len);
+	return -EAGAIN;
 }
 
 static const struct file_operations proc_vmcore_operations = {
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

linux-next.patch
linux-next-git-rejects.patch
arch-alpha-kernel-systblss-remove-debug-check.patch
i-need-old-gcc.patch
mm-mmu_notifier-re-fix-freed-page-still-mapped-in-secondary-mmu-fix.patch
drivers-video-implement-a-simple-framebuffer-driver.patch
shm-fix-null-pointer-deref-when-userspace-specifies-invalid-hugepage-size-fix.patch
revert-selftest-add-simple-test-for-soft-dirty-bit.patch
kmsg-honor-dmesg_restrict-sysctl-on-dev-kmsg-fix.patch
sound-soc-codecs-si476xc-dont-use-0bnnn.patch
drivers-iommu-msm_iommu_devc-fix-leak-and-clean-up-error-paths-fix.patch
posix-timers-correctly-get-dying-task-time-sample-in-posix_cpu_timer_schedule.patch
mm.patch
clear_refs-sanitize-accepted-commands-declaration.patch
mm-remove-compressed-copy-from-zram-in-memory-fix.patch
memory_hotplug-use-pgdat_resize_lock-in-__offline_pages-fix.patch
include-linux-mmh-add-page_aligned-helper.patch
vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment-fix.patch
vmalloc-introduce-remap_vmalloc_range_partial-fix.patch
vmcore-allocate-elf-note-segment-in-the-2nd-kernel-vmalloc-memory-fix.patch
vmcore-allow-user-process-to-remap-elf-note-segment-buffer-fix.patch
vmcore-support-mmap-on-proc-vmcore-fix.patch
include-linux-mmzoneh-cleanups.patch
include-linux-mmzoneh-cleanups-fix.patch
drop_caches-add-some-documentation-and-info-messsge.patch
memcg-debugging-facility-to-access-dangling-memcgs-fix.patch
dump_stack-serialize-the-output-from-dump_stack-fix.patch
panic-add-cpu-pid-to-warn_slowpath_common-in-warning-printks-fix.patch
lib-bitmapc-speed-up-bitmap_find_free_region-fix.patch
rbtree-remove-unneeded-include-fix.patch
checkpatch-warn-when-using-gccs-binary-constant-extension.patch
binfmt_elfc-use-get_random_int-to-fix-entropy-depleting.patch
fat-additions-to-support-fat_fallocate-fix.patch
idr-print-a-stack-dump-after-ida_remove-warning-fix.patch
partitions-add-aix-lvm-partition-support-files-checkpatch-fixes.patch
drivers-w1-slaves-w1_ds2408c-add-magic-sequence-to-disable-p0-test-mode-fix.patch
lib-add-lz4-compressor-module-fix.patch
crypto-add-lz4-cryptographic-api-fix.patch
debugging-keep-track-of-page-owners-fix-2-fix.patch
debugging-keep-track-of-page-owners-fix-2-fix-fix-fix.patch
journal_add_journal_head-debug.patch
kernel-forkc-export-kernel_thread-to-modules.patch
mutex-subsystem-synchro-test-module.patch
slab-leaks3-default-y.patch
put_bh-debug.patch