Re: [PATCH, v2] Fix potentially derefencing uninitialized 'r'.
From: Michal Hocko <hidden>
Date: 2012-03-29 12:25:52
Also in:
lkml
On Tue 21-02-12 17:58:23, Geunsik Lim wrote:
From: Geunsik Lim <redacted>
The warning seems to be bogus. The only caller is for_each_mem_pfn_range and even if we had type->cnt == 0 we would return before accessing r. I guess it would be more reasonable to silent the warning by __maybe_unused.
quoted hunk ↗ jump to hunk
v2: reorganize the code with better way to avoid compilation warning via the comment of Andrew Morton. v1: struct memblock_region 'r' will not be initialized potentially because of while() condition in __next_mem_pfn_range()function. Solve the compilation warning related problem by initializing r data structure. Signed-off-by: Geunsik Lim <redacted> --- mm/memblock.c | 8 ++++++-- 1 files changed, 6 insertions(+), 2 deletions(-)diff --git a/mm/memblock.c b/mm/memblock.c index 77b5f22..b8c40c5 100644 --- a/mm/memblock.c +++ b/mm/memblock.c@@ -673,14 +673,18 @@ void __init_memblock __next_mem_pfn_range(int *idx, int nid, struct memblock_type *type = &memblock.memory; struct memblock_region *r; - while (++*idx < type->cnt) { + do { r = &type->regions[*idx]; + if (++*idx < type->cnt) { if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size)) continue; if (nid == MAX_NUMNODES || nid == r->nid) break; - } + } else + break; + } while (1); + if (*idx >= type->cnt) { *idx = -1; return;-- 1.7.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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