2024年3月15日 08:21，Matthew Mirvish matthew@mm12.xyz 写道：
btree_iter is used in two ways: either allocated on the stack with a fixed size MAX_BSETS, or from a mempool with a dynamic size based on the specific cache set. Previously, the struct had a fixed-length array of size MAX_BSETS which was indexed out-of-bounds for the dynamically-sized iterators, which causes UBSAN to complain.
This patch uses the same approach as in bcachefs's sort_iter and splits the iterator into a btree_iter with a flexible array member and a btree_iter_stack which embeds a btree_iter as well as a fixed-length data array.
Cc: stable@vger.kernel.org Closes: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039368 Signed-off-by: Matthew Mirvish matthew@mm12.xyz
This patch is overall good to me. Let me take it and test for a while, and submit it to next merge window if the testing goes well.
Thanks.
Coly Li
drivers/md/bcache/bset.c | 44 +++++++++++++++++------------------ drivers/md/bcache/bset.h | 28 ++++++++++++++-------- drivers/md/bcache/btree.c | 40 ++++++++++++++++--------------- drivers/md/bcache/super.c | 5 ++-- drivers/md/bcache/sysfs.c | 2 +- drivers/md/bcache/writeback.c | 10 ++++---- 6 files changed, 70 insertions(+), 59 deletions(-)
[snipped]