From c1c201200a359cf3b6e2e36a4236cdca77a3cd8e Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Tue, 3 Feb 2009 07:47:29 +0100 Subject: bsg: Fix sense buffer bug in SG_IO When submitting requests via SG_IO, which does a sync io, a bsg_command is not allocated. So an in-Kernel sense_buffer was not set. However when calling blk_execute_rq() with no sense buffer one is provided from the stack. Now bsg at blk_complete_sgv4_hdr_rq() would check if rq->sense_len and a sense was requested by sg_io_v4 the rq->sense was copy_user() back, but by now it is already mangled stack memory. I have fixed that by forcing a sense_buffer when calling bsg_map_hdr(). The bsg_command->sense is provided in the write/read path like before, and on-the-stack buffer is provided when doing SG_IO. I have also fixed a dprintk message to print rq->errors in hex because of the scsi bit-field use of this member. For other block devices it does not matter anyway. Signed-off-by: Boaz Harrosh Acked-by: FUJITA Tomonori Signed-off-by: Jens Axboe --- block/bsg.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) (limited to 'block') diff --git a/block/bsg.c b/block/bsg.c index d414bb5607e..0ce8806dd0c 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -244,7 +244,8 @@ bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw) * map sg_io_v4 to a request. */ static struct request * -bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm) +bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm, + u8 *sense) { struct request_queue *q = bd->queue; struct request *rq, *next_rq = NULL; @@ -306,6 +307,10 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm) if (ret) goto out; } + + rq->sense = sense; + rq->sense_len = 0; + return rq; out: if (rq->cmd != rq->__cmd) @@ -348,9 +353,6 @@ static void bsg_rq_end_io(struct request *rq, int uptodate) static void bsg_add_command(struct bsg_device *bd, struct request_queue *q, struct bsg_command *bc, struct request *rq) { - rq->sense = bc->sense; - rq->sense_len = 0; - /* * add bc command to busy queue and submit rq for io */ @@ -419,7 +421,7 @@ static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr, { int ret = 0; - dprintk("rq %p bio %p %u\n", rq, bio, rq->errors); + dprintk("rq %p bio %p 0x%x\n", rq, bio, rq->errors); /* * fill in all the output members */ @@ -635,7 +637,7 @@ static int __bsg_write(struct bsg_device *bd, const char __user *buf, /* * get a request, fill in the blanks, and add to request queue */ - rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm); + rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm, bc->sense); if (IS_ERR(rq)) { ret = PTR_ERR(rq); rq = NULL; @@ -922,11 +924,12 @@ static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg) struct request *rq; struct bio *bio, *bidi_bio = NULL; struct sg_io_v4 hdr; + u8 sense[SCSI_SENSE_BUFFERSIZE]; if (copy_from_user(&hdr, uarg, sizeof(hdr))) return -EFAULT; - rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE); + rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE, sense); if (IS_ERR(rq)) return PTR_ERR(rq); -- cgit v1.2.3