From fdc772afcb68a532ba5a2f0fa5040657f0e998eb Mon Sep 17 00:00:00 2001
From: Gaowei Pu <pugaowei@gmail.com>
Date: Sat, 30 Nov 2019 17:51:03 -0800
Subject: [PATCH] mm/mmap.c: use IS_ERR_VALUE to check return value of
get_unmapped_area
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References: bnc#1155780 (VM/FS functional and performance backports)
Patch-mainline: v5.5-rc1
Git-commit: ff68dac6d65cd1347dad5d780dd8c90f29dc1b0b
get_unmapped_area() returns an address or -errno on failure. Historically
we have checked for the failure by offset_in_page() which is correct but
quite hard to read. Newer code started using IS_ERR_VALUE which is much
easier to read. Convert remaining users of offset_in_page as well.
[mhocko@suse.com: rewrite changelog]
[mhocko@kernel.org: fix mremap.c and uprobes.c sites also]
Link: http://lkml.kernel.org/r/20191012102512.28051-1-pugaowei@gmail.com
Signed-off-by: Gaowei Pu <pugaowei@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
kernel/events/uprobes.c | 2 +-
mm/mmap.c | 9 +++++----
mm/mremap.c | 4 ++--
3 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 84fa00497c49..249abfe76b99 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1405,7 +1405,7 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)
/* Try to map as high as possible, this is only a hint. */
area->vaddr = get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE,
PAGE_SIZE, 0, 0);
- if (area->vaddr & ~PAGE_MASK) {
+ if (IS_ERR_VALUE(area->vaddr)) {
ret = area->vaddr;
goto fail;
}
diff --git a/mm/mmap.c b/mm/mmap.c
index cebd101b3227..6d62db7af64c 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1405,7 +1405,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
* that it represents a valid section of the address space.
*/
addr = get_unmapped_area(file, addr, len, pgoff, flags);
- if (offset_in_page(addr))
+ if (IS_ERR_VALUE(addr))
return addr;
if (flags & MAP_FIXED_NOREPLACE) {
@@ -2965,15 +2965,16 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
struct rb_node **rb_link, *rb_parent;
pgoff_t pgoff = addr >> PAGE_SHIFT;
int error;
+ unsigned long mapped_addr;
/* Until we need other flags, refuse anything except VM_EXEC. */
if ((flags & (~VM_EXEC)) != 0)
return -EINVAL;
flags |= VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
- error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
- if (offset_in_page(error))
- return error;
+ mapped_addr = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
+ if (IS_ERR_VALUE(mapped_addr))
+ return mapped_addr;
error = mlock_future_check(mm, mm->def_flags, len);
if (error)
diff --git a/mm/mremap.c b/mm/mremap.c
index fc241d23cd97..67324cf1ad29 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -558,7 +558,7 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
ret = get_unmapped_area(vma->vm_file, new_addr, new_len, vma->vm_pgoff +
((addr - vma->vm_start) >> PAGE_SHIFT),
map_flags);
- if (offset_in_page(ret))
+ if (IS_ERR_VALUE(ret))
goto out1;
ret = move_vma(vma, addr, old_len, new_len, new_addr, locked, uf,
@@ -703,7 +703,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
vma->vm_pgoff +
((addr - vma->vm_start) >> PAGE_SHIFT),
map_flags);
- if (offset_in_page(new_addr)) {
+ if (IS_ERR_VALUE(new_addr)) {
ret = new_addr;
goto out;
}