diff options
| author | Tony Luck <tony.luck@intel.com> | 2019-01-12 01:46:37 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-27 12:08:54 +0300 |
| commit | 752f0bcb5d4d97b0ffcfe1c9f97c6b85d4245160 (patch) | |
| tree | 1558ee9d571dc91b330b5932b02f08d94c5eaf3c /drivers/acpi | |
| parent | 99b490e3a0f31ef9b9318e96c2754e7977ceb9a8 (diff) | |
| download | linux-752f0bcb5d4d97b0ffcfe1c9f97c6b85d4245160.tar.xz | |
acpi/nfit: Fix race accessing memdev in nfit_get_smbios_id()
[ Upstream commit 0919871ac37fdcf46c7657da0f1742efe096b399 ]
Possible race accessing memdev structures after dropping the
mutex. Dan Williams says this could race against another thread
that is doing:
# echo "ACPI0012:00" > /sys/bus/acpi/drivers/nfit/unbind
Reported-by: Jane Chu <jane.chu@oracle.com>
Fixes: 23222f8f8dce ("acpi, nfit: Add function to look up nvdimm...")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/nfit/core.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index ea59c01ce8db..f530d3541242 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -719,6 +719,7 @@ int nfit_get_smbios_id(u32 device_handle, u16 *flags) struct acpi_nfit_memory_map *memdev; struct acpi_nfit_desc *acpi_desc; struct nfit_mem *nfit_mem; + u16 physical_id; mutex_lock(&acpi_desc_lock); list_for_each_entry(acpi_desc, &acpi_descs, list) { @@ -726,10 +727,11 @@ int nfit_get_smbios_id(u32 device_handle, u16 *flags) list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) { memdev = __to_nfit_memdev(nfit_mem); if (memdev->device_handle == device_handle) { + *flags = memdev->flags; + physical_id = memdev->physical_id; mutex_unlock(&acpi_desc->init_mutex); mutex_unlock(&acpi_desc_lock); - *flags = memdev->flags; - return memdev->physical_id; + return physical_id; } } mutex_unlock(&acpi_desc->init_mutex); |