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| author | Liviu Dudau <liviu@dudau.co.uk> | 2019-03-05 15:42:54 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-03-05 21:07:14 -0800 |
| commit | 6ade20327dbb808882888ed8ccded71e93067cf9 (patch) | |
| tree | 91f168af07d0bd54d5df81835ace554a64b1c0c1 /mm/vmalloc.c | |
| parent | abd02ac616e32d818a0478e68924beac8ba5e5d8 (diff) | |
| download | lwn-6ade20327dbb808882888ed8ccded71e93067cf9.tar.gz lwn-6ade20327dbb808882888ed8ccded71e93067cf9.zip | |
mm/vmalloc.c: don't dereference possible NULL pointer in __vunmap()
find_vmap_area() can return a NULL pointer and we're going to
dereference it without checking it first. Use the existing
find_vm_area() function which does exactly what we want and checks for
the NULL pointer.
Link: http://lkml.kernel.org/r/20181228171009.22269-1-liviu@dudau.co.uk
Fixes: f3c01d2f3ade ("mm: vmalloc: avoid racy handling of debugobjects in vunmap")
Signed-off-by: Liviu Dudau <liviu@dudau.co.uk>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Chintan Pandya <cpandya@codeaurora.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/vmalloc.c')
| -rw-r--r-- | mm/vmalloc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 871e41c55e23..806047d7fda3 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1505,7 +1505,7 @@ static void __vunmap(const void *addr, int deallocate_pages) addr)) return; - area = find_vmap_area((unsigned long)addr)->vm; + area = find_vm_area(addr); if (unlikely(!area)) { WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", addr); |