summaryrefslogtreecommitdiffstats
path: root/drivers/dma-buf
diff options
context:
space:
mode:
authorChristian König <christian.koenig@amd.com>2020-10-09 15:08:55 +0200
committerChristian König <christian.koenig@amd.com>2020-11-05 13:03:43 +0100
commit0227da01f2559626396af5f6c7453360db86c1f6 (patch)
tree4bd2c28e4a1de36378eb7a45be3e81b52318f043 /drivers/dma-buf
parentea86f3defd55f141a44146e66cbf8ffb683d60da (diff)
downloadlinux-0227da01f2559626396af5f6c7453360db86c1f6.tar.bz2
mm: mmap: fix fput in error path v2
Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..." adds a workaround for a bug in mmap_region. As the comment states ->mmap() callback can change vma->vm_file and so we might call fput() on the wrong file. Revert the workaround and proper fix this in mmap_region. v2: drop the extra if in dma_buf_mmap as well Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://patchwork.freedesktop.org/patch/394772/
Diffstat (limited to 'drivers/dma-buf')
-rw-r--r--drivers/dma-buf/dma-buf.c20
1 files changed, 3 insertions, 17 deletions
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 556f62e8b196..3d22dff1dab9 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -1166,9 +1166,6 @@ EXPORT_SYMBOL_GPL(dma_buf_end_cpu_access);
int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
unsigned long pgoff)
{
- struct file *oldfile;
- int ret;
-
if (WARN_ON(!dmabuf || !vma))
return -EINVAL;
@@ -1186,22 +1183,11 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
return -EINVAL;
/* readjust the vma */
- get_file(dmabuf->file);
- oldfile = vma->vm_file;
- vma->vm_file = dmabuf->file;
+ fput(vma->vm_file);
+ vma->vm_file = get_file(dmabuf->file);
vma->vm_pgoff = pgoff;
- ret = dmabuf->ops->mmap(dmabuf, vma);
- if (ret) {
- /* restore old parameters on failure */
- vma->vm_file = oldfile;
- fput(dmabuf->file);
- } else {
- if (oldfile)
- fput(oldfile);
- }
- return ret;
-
+ return dmabuf->ops->mmap(dmabuf, vma);
}
EXPORT_SYMBOL_GPL(dma_buf_mmap);