kernel/linux.git/block/bio-integrity.c, branch v7.0.11

block: bio-integrity: Fix null-ptr-deref in bio_integrity_map_user()

2026-06-01T15:54:41+00:00

[ Upstream commit 8582792cf23b3d94674d4d838f7cde9a28d0fcaf ] pin_user_pages_fast() can partially succeed and return the number of pages that were actually pinned. However, the bio_integrity_map_user() does not handle this partial pinning. This leads to a general protection fault since bvec_from_pages() dereferences an unpinned page address, which is 0. To fix this, add a check to verify that all requested memory is pinned. If partial pinning occurs, unpin the memory and return -EFAULT. Kernel Oops: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 UID: 0 PID: 1061 Comm: nvme-passthroug Not tainted 7.0.0-11783-g90957f9314e8-dirty #16 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 RIP: 0010:bio_integrity_map_user.cold+0x1b0/0x9d6 Fixes: 492c5d455969 ("block: bio-integrity: directly map user buffers") Acked-by: Chao Shi Acked-by: Weidong Zhu Acked-by: Dave Tian Signed-off-by: Sungwoo Kim Tested-by: Shin'ichiro Kawasaki Link: https://github.com/linux-blktests/blktests/pull/244 Link: https://patch.msgid.link/20260512050929.541397-2-iam@sung-woo.kim Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: don't overwrite bip_vcnt in bio_integrity_copy_user()

2026-06-01T15:54:41+00:00

[ Upstream commit 637ad3a56a3b889527d1dacea6fea2a8bd648140 ] bio_integrity_add_page() already sets bip_vcnt to 1 for the bounce segment. Overwriting it with nr_vecs breaks bip_vcnt <= bip_max_vcnt on WRITE (bip_max_vcnt is 1), so the gap-merge checks in block/blk.h read past the bip_vec[] flex array. On READ the read is in bounds but lands on a saved user bvec instead of the bounce. The line was added for split propagation, but bio_integrity_clone() doesn't copy bip_vcnt and BIP_CLONE_FLAGS excludes BIP_COPY_USER. Fixes: 3991657ae707 ("block: set bip_vcnt correctly") Signed-off-by: David Carlier Reviewed-by: Christoph Hellwig Link: https://patch.msgid.link/20260511215151.346228-1-devnexen@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: relax pgmap check in bio_add_page for compatible zone device pages

2026-05-07T04:13:54+00:00

commit 41c665aae2b5dbecddddcc8ace344caf630cc7a4 upstream. bio_add_page() and bio_integrity_add_page() reject pages from different dev_pagemaps entirely, returning 0 even when those pages have compatible DMA mapping requirements. This forces callers to start a new bio when buffers span pgmap boundaries, even though the pages could safely coexist as separate bvec entries. This matters for guests where memory is registered through devm_memremap_pages() with MEMORY_DEVICE_GENERIC in multiple calls, creating separate dev_pagemaps for each chunk. When a direct I/O buffer spans two such chunks, bio_add_page() rejects the second page, forcing an unnecessary bio split or I/O failure. Introduce zone_device_pages_compatible() in blk.h to check whether two pages can coexist in the same bio as separate bvec entries. The block DMA iterator (blk_dma_map_iter_start) caches the P2PDMA mapping state from the first segment and applies it to all others, so P2PDMA pages from different pgmaps must not be mixed, and neither must P2PDMA and non-P2PDMA pages. All other combinations (MEMORY_DEVICE_GENERIC pages from different pgmaps, or MEMORY_DEVICE_GENERIC with normal RAM) use the same dma_map_phys path and are safe. Replace the blanket zone_device_pages_have_same_pgmap() rejection with zone_device_pages_compatible(), while keeping zone_device_pages_have_same_pgmap() as a merge guard. Pages from different pgmaps can be added as separate bvec entries but must not be coalesced into the same segment, as that would make it impossible to recover the correct pgmap via page_pgmap(). Fixes: 49580e690755 ("block: add check when merging zone device pages") Cc: stable@vger.kernel.org Signed-off-by: Naman Jain Reviewed-by: Christoph Hellwig Link: https://patch.msgid.link/20260410153414.4159050-3-namjain@linux.microsoft.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

block: make bio auto-integrity deadlock safe

2025-11-04T19:41:50+00:00

The current block layer automatic integrity protection allocates the actual integrity buffer, which has three problems: - because it happens at the bottom of the I/O stack and doesn't use a mempool it can deadlock under load - because the data size in a bio is almost unbounded when using lage folios it can relatively easily exceed the maximum kmalloc size - even when it does not exceed the maximum kmalloc size, it could exceed the maximum segment size of the device Fix this by limiting the I/O size so that we can allocate at least a 2MiB integrity buffer, i.e. 128MiB for 8 byte PI and 512 byte integrity intervals, and create a mempool as a last resort for this maximum size, mirroring the scheme used for bvecs. As a nice upside none of this can fail now, so we remove the error handling and open code the trivial addition of the bip vec. The new allocation helpers sit outside of bio-integrity-auto.c because I plan to reuse them for file system based PI in the near future. Fixes: 7ba1ba12eeef ("block: Block layer data integrity support") Signed-off-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Reviewed-by: Johannes Thumshirn Reviewed-by: Anuj Gupta Reviewed-by: Kanchan Joshi Signed-off-by: Jens Axboe

blk-integrity: enable p2p source and destination

2025-09-09T16:33:27+00:00

Set the extraction flags to allow p2p pages for the metadata buffer if the block device allows it. Similar to data payloads, ensure the bio does not use merging if we see a p2p page. Reviewed-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Signed-off-by: Keith Busch Signed-off-by: Jens Axboe

blk-integrity: use simpler alignment check

2025-09-09T16:27:01+00:00

We're checking length and addresses against the same alignment value, so use the more simple iterator check. Signed-off-by: Keith Busch Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: don't merge different kinds of P2P transfers in a single bio

2025-06-30T21:50:32+00:00

To get out of the DMA mapping helpers having to check every segment for it's P2P status, ensure that bios either contain P2P transfers or non-P2P transfers, and that a P2P bio only contains ranges from a single device. This means we do the page zone access in the bio add path where it should be still page hot, and will only have do the fairly expensive P2P topology lookup once per bio down in the DMA mapping path, and only for already marked bios. Signed-off-by: Christoph Hellwig Reviewed-by: Keith Busch Reviewed-by: Logan Gunthorpe Reviewed-by: Leon Romanovsky Link: https://lore.kernel.org/r/20250625113531.522027-2-hch@lst.de Signed-off-by: Jens Axboe

block: drop direction param from bio_integrity_copy_user()

2025-06-03T18:45:45+00:00

direction is determined from bio, which is already passed in. Compute op_is_write(bio_op(bio)) directly instead of converting it to an iter direction and back to a bool. Signed-off-by: Caleb Sander Mateos Reviewed-by: Keith Busch Reviewed-by: Anuj Gupta Link: https://lore.kernel.org/r/20250603183133.1178062-1-csander@purestorage.com Signed-off-by: Jens Axboe