diff options
| author | Long Li <lonuxli.64@gmail.com> | 2020-08-06 23:18:28 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-07 11:33:22 -0700 |
| commit | 444050990db4abdf0c85ca6050542b888ba316a1 (patch) | |
| tree | 94acbfbb4ec5aef67b237176977b953c7c8ad929 /mm/slab.c | |
| parent | dabc3e291d56e3125113101bc6d53d1a1738294d (diff) | |
| download | linux-444050990db4abdf0c85ca6050542b888ba316a1.tar.gz | |
mm, slab: check GFP_SLAB_BUG_MASK before alloc_pages in kmalloc_order
kmalloc cannot allocate memory from HIGHMEM. Allocating large amounts of
memory currently bypasses the check and will simply leak the memory when
page_address() returns NULL. To fix this, factor the GFP_SLAB_BUG_MASK
check out of slab & slub, and call it from kmalloc_order() as well. In
order to make the code clear, the warning message is put in one place.
Signed-off-by: Long Li <lonuxli.64@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Link: http://lkml.kernel.org/r/20200704035027.GA62481@lilong
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/slab.c')
| -rw-r--r-- | mm/slab.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/mm/slab.c b/mm/slab.c index 77e90f9de9c0c4..0781a2384441c7 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2589,13 +2589,9 @@ static struct page *cache_grow_begin(struct kmem_cache *cachep, * Be lazy and only check for valid flags here, keeping it out of the * critical path in kmem_cache_alloc(). */ - if (unlikely(flags & GFP_SLAB_BUG_MASK)) { - gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; - flags &= ~GFP_SLAB_BUG_MASK; - pr_warn("Unexpected gfp: %#x (%pGg). Fixing up to gfp: %#x (%pGg). Fix your code!\n", - invalid_mask, &invalid_mask, flags, &flags); - dump_stack(); - } + if (unlikely(flags & GFP_SLAB_BUG_MASK)) + flags = kmalloc_fix_flags(flags); + WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK); |