From: Michal Feix We should check magic sequence in reply packet before trying to find request with it's request handle. This also solves the problem with "Unexpected reply" message beeing logged, when packet with invalid magic is received. Signed-off-by: Michal Feix Acked-by: Paul Clements Signed-off-by: Andrew Morton --- drivers/block/nbd.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff -puN drivers/block/nbd.c~nbd-check-magic-before-doing-anything-else drivers/block/nbd.c --- a/drivers/block/nbd.c~nbd-check-magic-before-doing-anything-else +++ a/drivers/block/nbd.c @@ -300,6 +300,15 @@ static struct request *nbd_read_stat(str lo->disk->disk_name, result); goto harderror; } + + if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { + printk(KERN_ERR "%s: Wrong magic (0x%lx)\n", + lo->disk->disk_name, + (unsigned long)ntohl(reply.magic)); + result = -EPROTO; + goto harderror; + } + req = nbd_find_request(lo, reply.handle); if (unlikely(IS_ERR(req))) { result = PTR_ERR(req); @@ -312,13 +321,6 @@ static struct request *nbd_read_stat(str goto harderror; } - if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { - printk(KERN_ERR "%s: Wrong magic (0x%lx)\n", - lo->disk->disk_name, - (unsigned long)ntohl(reply.magic)); - result = -EPROTO; - goto harderror; - } if (ntohl(reply.error)) { printk(KERN_ERR "%s: Other side returned error (%d)\n", lo->disk->disk_name, ntohl(reply.error)); _