cxl/acpi: Fix a use-after-free in cxl_parse_cfmws()
authorBreno Leitao <leitao@debian.org>
Fri, 14 Jul 2023 09:31:45 +0000 (02:31 -0700)
committerVishal Verma <vishal.l.verma@intel.com>
Tue, 18 Jul 2023 17:55:02 +0000 (11:55 -0600)
commit4cf67d3cc9994a59cf77bb9c0ccf9007fe916afe
treef4e04b7a382233188e9084993f2ced0cbc3a1e9d
parent004ff1b049dda0ec484328a78fc550a9cfc0942b
cxl/acpi: Fix a use-after-free in cxl_parse_cfmws()

KASAN and KFENCE detected an user-after-free in the CXL driver. This
happens in the cxl_decoder_add() fail path. KASAN prints the following
error:

   BUG: KASAN: slab-use-after-free in cxl_parse_cfmws (drivers/cxl/acpi.c:299)

This happens in cxl_parse_cfmws(), where put_device() is called,
releasing cxld, which is accessed later.

Use the local variables in the dev_err() instead of pointing to the
released memory. Since the dev_err() is printing a resource, change the open
coded print format to use the %pr format specifier.

Fixes: e50fe01e1f2a ("cxl/core: Drop ->platform_res attribute for root decoders")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20230714093146.2253438-1-leitao@debian.org
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
drivers/cxl/acpi.c