diff options
| author | Minchan Kim <minchan@kernel.org> | 2014-01-30 15:45:58 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-06 11:34:06 -0800 |
| commit | a76055cd067d7d6aee361b60b3fa5338c0a6f017 (patch) | |
| tree | 586e99e23ebc944d4a3cd2a8d071ce145f42467a | |
| parent | 9047ec62665cb8931840214b038cc1d22c4ed2e4 (diff) | |
zram: fix race between reset and flushing pending work
commit da4a04126baa3be03bc566d4a2ee0944c5e783d0 upstream.
Dan and Sergey reported that there is a racy between reset and flushing
of pending work so that it could make oops by freeing zram->meta in
reset while zram_slot_free can access zram->meta if new request is
adding during the race window.
This patch moves flush after taking init_lock so it prevents new request
so that it closes the race.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/zram/zram_drv.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c index 3277d9838f4e..bfbfe579d896 100644 --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -552,14 +552,14 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity) size_t index; struct zram_meta *meta; - flush_work(&zram->free_work); - down_write(&zram->init_lock); if (!zram->init_done) { up_write(&zram->init_lock); return; } + flush_work(&zram->free_work); + meta = zram->meta; zram->init_done = 0; |