From 616d9390b1db74097735ac58346d164d2fa2d16b Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" <kys@microsoft.com> Date: Fri, 27 Mar 2015 00:27:18 -0700 Subject: [PATCH] scsi: storvsc: Fix a bug in copy_from_bounce_buffer() commit 8de580742fee8bc34d116f57a20b22b9a5f08403 upstream. We may exit this function without properly freeing up the maapings we may have acquired. Fix the bug. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Long Li <longli@microsoft.com> Signed-off-by: James Bottomley <JBottomley@Odin.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> --- drivers/scsi/storvsc_drv.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 86b05151fdab..97892f258043 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -739,21 +739,22 @@ static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, if (bounce_sgl[j].length == PAGE_SIZE) { /* full..move to next entry */ sg_kunmap_atomic(bounce_addr); + bounce_addr = 0; j++; + } - /* if we need to use another bounce buffer */ - if (srclen || i != orig_sgl_count - 1) - bounce_addr = sg_kmap_atomic(bounce_sgl,j); + /* if we need to use another bounce buffer */ + if (srclen && bounce_addr == 0) + bounce_addr = sg_kmap_atomic(bounce_sgl, j); - } else if (srclen == 0 && i == orig_sgl_count - 1) { - /* unmap the last bounce that is < PAGE_SIZE */ - sg_kunmap_atomic(bounce_addr); - } } sg_kunmap_atomic(src_addr - orig_sgl[i].offset); } + if (bounce_addr) + sg_kunmap_atomic(bounce_addr); + local_irq_restore(flags); return total_copied; -- 2.30.9