From: Dave Jiang Date: Wed, 11 Jul 2018 17:10:11 +0000 (-0700) Subject: nfit: fix unchecked dereference in acpi_nfit_ctl X-Git-Tag: Ubuntu-4.15.0-56.62~2520 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=7515120f76730a07fa4b6106d84112e485b8de9d;p=mirror_ubuntu-bionic-kernel.git nfit: fix unchecked dereference in acpi_nfit_ctl BugLink: https://bugs.launchpad.net/bugs/1835845 [ Upstream commit ee6581ceba7f8314b81b2f2a81f1cf3f67c679e2 ] Incremental patch to fix the unchecked dereference in acpi_nfit_ctl. Reported by Dan Carpenter: "acpi/nfit: fix cmd_rc for acpi_nfit_ctl to always return a value" from Jun 28, 2018, leads to the following Smatch complaint: drivers/acpi/nfit/core.c:578 acpi_nfit_ctl() warn: variable dereferenced before check 'cmd_rc' (see line 411) drivers/acpi/nfit/core.c 410 411 *cmd_rc = -EINVAL; ^^^^^^^^^^^^^^^^^^ Patch adds unchecked dereference. Fixes: c1985cefd844 ("acpi/nfit: fix cmd_rc for acpi_nfit_ctl to always return a value") Signed-off-by: Dave Jiang Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Kamal Mostafa Signed-off-by: Khalid Elmously --- diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index b267d91f9538..2ac3d37530f3 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -413,7 +413,8 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, const guid_t *guid; int rc, i; - *cmd_rc = -EINVAL; + if (cmd_rc) + *cmd_rc = -EINVAL; func = cmd; if (cmd == ND_CMD_CALL) { call_pkg = buf; @@ -525,7 +526,8 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, * If we return an error (like elsewhere) then caller wouldn't * be able to rely upon data returned to make calculation. */ - *cmd_rc = 0; + if (cmd_rc) + *cmd_rc = 0; return 0; }