Commit ba38980a authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Christian Brauner
Browse files

reiserfs: Check the return value from __getblk() 



__getblk() can return a NULL pointer if we run out of memory or if we
try to access beyond the end of the device; check it and handle it
appropriately.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/lkml/CAFcO6XOacq3hscbXevPQP7sXRoYFz34ZdKPYjmd6k5sZuhGFDw@mail.gmail.com/


Tested-by: default avatarbutt3rflyh4ck <butterflyhuangxx@gmail.com>
Fixes: 1da177e4 ("Linux-2.6.12-rc2") # probably introduced in 2002
Acked-by: default avatarEdward Shishkin <edward.shishkin@gmail.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent e2393b8f

fs/reiserfs/journal.c

+3 −1
Original line number Diff line number Diff line
@@ -2326,7 +2326,7 @@ static struct buffer_head *reiserfs_breada(struct block_device *dev, 
	int i, j;



	bh = __getblk(dev, block, bufsize);

	if (buffer_uptodate(bh))

	if (!bh || buffer_uptodate(bh))

		return (bh);



	if (block + BUFNR > max_block) {
@@ -2336,6 +2336,8 @@ static struct buffer_head *reiserfs_breada(struct block_device *dev, 
	j = 1;

	for (i = 1; i < blocks; i++) {

		bh = __getblk(dev, block + i, bufsize);

		if (!bh)

			break;

		if (buffer_uptodate(bh)) {

			brelse(bh);

			break;