android/android_kernel_asus_sm8350
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

nvmem: check for NULL reg_read and reg_write before dereferencing

Browse Source 
commit 3c91ef69a3e94f78546b246225ed573fbf1735b4 upstream.

Return -EPERM if reg_read is NULL in bin_attr_nvmem_read() or if
reg_write is NULL in bin_attr_nvmem_write().

This prevents NULL dereferences such as the one described in
03cd45d2e219 ("thunderbolt: Prevent crash if non-active NVMem file is
read")

Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-10-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Nicholas Johnson 2020-03-10 13:22:52 +00:00 committed by Greg Kroah-Hartman
parent 98b32db072
commit 4d60b72514
1 changed files with 6 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/nvmem/nvmem-sysfs.c
View File

@ -56,6 +56,9 @@ static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj,
count = round_down(count, nvmem->word_size);
if (!nvmem->reg_read)
return -EPERM;
rc = nvmem->reg_read(nvmem->priv, pos, buf, count);
if (rc)
@ -90,6 +93,9 @@ static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
count = round_down(count, nvmem->word_size);
if (!nvmem->reg_write)
return -EPERM;
rc = nvmem->reg_write(nvmem->priv, pos, buf, count);
if (rc)