Commit a3e713b5 authored Oct 30, 2005 by Andrew Morton Committed by Linus Torvalds Oct 30, 2005

[PATCH] __bread oops fix



If a filesystem passes an idiotic blocksize into bread(), __getblk_slow() will
warn and will return NULL.  We have a report (from Hubert Tonneau
<hubert.tonneau@fullpliant.org>) of isofs_fill_super() doing this (passing in
a silly block size) against an unplugged CDROM drive.

But a couple of __getblk_slow() callers forgot to check for the NULL bh, hence
oops.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 727a53bd

fs/buffer.c

+5 −3

Original line number	Diff line number	Diff line
		@@ -1478,9 +1478,11 @@ EXPORT_SYMBOL(__getblk);
		void __breadahead(struct block_device *bdev, sector_t block, int size)
		{
		struct buffer_head *bh = __getblk(bdev, block, size);
		if (likely(bh)) {
		ll_rw_block(READA, 1, &bh);
		brelse(bh);
		}
		}
		EXPORT_SYMBOL(__breadahead);

		/**
		@@ -1497,7 +1499,7 @@ __bread(struct block_device *bdev, sector_t block, int size)
		{
		struct buffer_head *bh = __getblk(bdev, block, size);

		if (!buffer_uptodate(bh))
		if (likely(bh) && !buffer_uptodate(bh))
		bh = __bread_slow(bh);
		return bh;
		}

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