Re: [PATCH] block: fix potential invalid pointer dereference in blk_add_partition

From: Bart Van Assche
Date: Mon Sep 09 2024 - 12:56:28 EST


On 9/8/24 10:10 AM, Riyan Dhiman wrote:
The blk_add_partition() function initially used a single if-condition
(IS_ERR(part)) to check for errors when adding a partition. This was
modified to handle the specific case of -ENXIO separately, allowing the
function to proceed without logging the error in this case. However,
this change unintentionally left a path where md_autodetect_dev()
could be called without confirming that part is a valid pointer.

This commit separates the error handling logic by splitting the
initial if-condition, improving code readability and handling specific
error scenarios explicitly. The function now distinguishes the general
error case from -ENXIO without altering the existing behavior of
md_autodetect_dev() calls.

Fixes: b72053072c0b (block: allow partitions on host aware zone devices)

Signed-off-by: Riyan Dhiman <riyandhiman14@xxxxxxxxx>

No blank line between the Fixes: and Signed-off-by: tags please.
Additionally, please Cc the author of a patch when posting a fix for a
patch.

Thanks,

Bart.