kmemleak: Do not use off-slab management with SLAB_NOLEAKTRACE (e7cb55b9) · Commits · 戴 / test

With the slab allocator, if off-slab management is enabled for the kmem_caches used by kmemleak, it leads to recursive calls into kmemleak_alloc(). Off-slab management can be triggered by other config options increasing the slab size, e.g. DEBUG_PAGEALLOC. Reported-by:

Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by:

Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by:

Catalin Marinas <catalin.marinas@arm.com>

mm/slab.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -2261,9 +2261,11 @@ kmem_cache_create (const char *name, size_t size, size_t align,
		/*
		* Determine if the slab management is 'on' or 'off' slab.
		* (bootstrapping cannot cope with offslab caches so don't do
		* it too early on.)
		* it too early on. Always use on-slab management when
		* SLAB_NOLEAKTRACE to avoid recursive calls into kmemleak)
		*/
		if ((size >= (PAGE_SIZE >> 3)) && !slab_early_init)
		if ((size >= (PAGE_SIZE >> 3)) && !slab_early_init &&
		!(flags & SLAB_NOLEAKTRACE))
		/*
		* Size is large, assume best to place the slab management obj
		* off-slab (should allow better packing of objs).

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