module/decompress: Never use kunmap() for local un-mappings
authorFabio M. De Francesco <fmdefrancesco@gmail.com>
Wed, 15 Mar 2023 12:52:56 +0000 (13:52 +0100)
committerLuis Chamberlain <mcgrof@kernel.org>
Wed, 22 Mar 2023 23:12:35 +0000 (16:12 -0700)
Use kunmap_local() to unmap pages locally mapped with kmap_local_page().

kunmap_local() must be called on the kernel virtual address returned by
kmap_local_page(), differently from how we use kunmap() which instead
expects the mapped page as its argument.

In module_zstd_decompress() we currently map with kmap_local_page() and
unmap with kunmap(). This breaks the code and so it should be fixed.

Cc: Piotr Gorski <piotrgorski@cachyos.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Fixes: 169a58ad824d ("module/decompress: Support zstd in-kernel decompression")
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Piotr Gorski <piotrgorski@cachyos.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
kernel/module/decompress.c

index bb79ac1a6d8f792afde2228d26e076ff1afaa9e8..7ddc87bee2741f3b79456d4b5b1e1d85ca703fa5 100644 (file)
@@ -267,7 +267,7 @@ static ssize_t module_zstd_decompress(struct load_info *info,
                zstd_dec.size = PAGE_SIZE;
 
                ret = zstd_decompress_stream(dstream, &zstd_dec, &zstd_buf);
-               kunmap(page);
+               kunmap_local(zstd_dec.dst);
                retval = zstd_get_error_code(ret);
                if (retval)
                        break;