In the Linux kernel, the following vulnerability has been resolved:
md/raid10: reset read_slot when reusing r10bio for discard
put_all_bios() always drops devs[i].bio, but it only drops devs[i].repl_bio when r10_bio->read_slot < 0. If discard reuses an r10bio that was previously used for a read, read_slot can still be non-negative, and discard cleanup can skip bio_put() on repl_bio.
Reset read_slot to -1 when preparing an r10bio for discard so the replacement bio is always released correctly.
References
- https://git.kernel.org/stable/c/3cb2a606ce4902eceabe68338df0653312f861f8
- https://git.kernel.org/stable/c/561c9711e4f545d6464a023168bdee03b00fa945
- https://git.kernel.org/stable/c/6b8a26af065ddc93de2aa5c9f0df98dce9723442
- https://git.kernel.org/stable/c/742e4afd247d9c972695227716b03d432a7e1d26
- https://git.kernel.org/stable/c/b7313f23ea5a79b199a007bfad64a866cc2c22e7
- https://git.kernel.org/stable/c/ce3030e92f14362880055de5fe3c258971118853
- https://git.kernel.org/stable/c/eb04e3e9c14ed15914f5fd2eae8b6435f54f095f