Commit 6a648fa7 authored Aug 10, 2007 by Badari Pulavarty Committed by Linus Torvalds Aug 11, 2007

direct-io: fix error-path crashes

Need to initialize map_bh.b_state to zero.  Otherwise, in case of a faulty
user-buffer its possible to go into dio_zero_block() and submit a page by
mistake - since it checks for buffer_new().

http://marc.info/?l=linux-kernel&m=118551339032528&w=2



akpm: Linus had a (better) patch to just do a kzalloc() in there, but it got
lost.  Probably this version is better for -stable anwyay.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Joe Jin <joe.jin@oracle.com>
Acked-by: Zach Brown <zach.brown@oracle.com>
Cc: gurudas pai <gurudas.pai@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b291aa7a

fs/direct-io.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -974,6 +974,7 @@ direct_io_worker(int rw, struct kiocb iocb, struct inode inode,
		dio->get_block = get_block;
		dio->end_io = end_io;
		dio->map_bh.b_private = NULL;
		dio->map_bh.b_state = 0;
		dio->final_block_in_bio = -1;
		dio->next_block_for_io = -1;

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