block: initialize integrity buffer to zero before writing it to media
[ Upstream commit 899ee2c3829c5ac14bfc7d3c4a5846c0b709b78f ]
Metadata added by bio_integrity_prep is using plain kmalloc, which leads
to random kernel memory being written media. For PI metadata this is
limited to the app tag that isn't used by kernel generated metadata,
but for non-PI metadata the entire buffer leaks kernel memory.
Fix this by adding the __GFP_ZERO flag to allocations for writes.
BUG=b/362701216
TEST=presubmit
RELEASE_NOTE=Fixes CVE-2024-43854 in the Linux kernel
cos-patch: security-moderate
Fixes: 7ba1ba12eeef ("block: Block layer data integrity support")
Change-Id: I1792e6317e8a47514863f2ec39ba7aedb8b24cc4
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/79520
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Oleksandr Tymoshenko <ovt@google.com>
1 file changed
