| From | Greg Kroah-Hartman <> | Subject | [ 21/54] md: Avoid write invalid address if read_seqretry returned true. | Date | Fri, 30 Nov 2012 10:55:52 -0800 |
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3.6-stable review patch. If anyone has any objections, please let me know.
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From: majianpeng <majianpeng@gmail.com>
commit 35f9ac2dcec8f79d7059ce174fd7b7ee3290d620 upstream.
If read_seqretry returned true and bbp was changed, it will write invalid address which can cause some serious problem.
This bug was introduced by commit v3.0-rc7-130-g2699b67. So fix is suitable for 3.0.y thru 3.6.y.
Reported-by: zhuwenfeng@kedacom.com Tested-by: zhuwenfeng@kedacom.com Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/md/md.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1832,10 +1832,10 @@ retry: memset(bbp, 0xff, PAGE_SIZE); for (i = 0 ; i < bb->count ; i++) { - u64 internal_bb = *p++; + u64 internal_bb = p[i]; u64 store_bb = ((BB_OFFSET(internal_bb) << 10) | BB_LEN(internal_bb)); - *bbp++ = cpu_to_le64(store_bb); + bbp[i] = cpu_to_le64(store_bb); } bb->changed = 0; if (read_seqretry(&bb->lock, seq))
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