6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Marek Vasut <marex@xxxxxxx>
commit da9596955c05966768364ab1cad2f43fcddc6f06 upstream.
The bin_attr_nvmem_write() must check the read_only flag and block
writes on read-only devices, now that a nvmem device can be switched
between read-write and read-only mode at runtime using the force_ro
attribute. Add the missing check.
Fixes: 9d7eb234ac7a ("nvmem: core: Implement force_ro sysfs attribute")
Cc: Stable@xxxxxxxxxxxxxxx
Signed-off-by: Marek Vasut <marex@xxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20241030140253.40445-2-srinivas.kandagatla@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/nvmem/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -267,7 +267,7 @@ static ssize_t bin_attr_nvmem_write(stru
count = round_down(count, nvmem->word_size);
- if (!nvmem->reg_write)
+ if (!nvmem->reg_write || nvmem->read_only)
return -EPERM;
rc = nvmem_reg_write(nvmem, pos, buf, count);
