From 26e197b7f9240a4ac301dd0ad520c0c697c2ea7d Mon Sep 17 00:00:00 2001 From: Riyan Dhiman Date: Wed, 11 Sep 2024 18:59:54 +0530 Subject: [PATCH] block: fix potential invalid pointer dereference in blk_add_partition 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 Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20240911132954.5874-1-riyandhiman14@gmail.com Signed-off-by: Jens Axboe --- block/partitions/core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/block/partitions/core.c b/block/partitions/core.c index ab76e64f0f6c..5bd7a603092e 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -555,9 +555,11 @@ static bool blk_add_partition(struct gendisk *disk, part = add_partition(disk, p, from, size, state->parts[p].flags, &state->parts[p].info); - if (IS_ERR(part) && PTR_ERR(part) != -ENXIO) { - printk(KERN_ERR " %s: p%d could not be added: %pe\n", - disk->disk_name, p, part); + if (IS_ERR(part)) { + if (PTR_ERR(part) != -ENXIO) { + printk(KERN_ERR " %s: p%d could not be added: %pe\n", + disk->disk_name, p, part); + } return true; }