block: Fix iterating over an empty bio with bio_for_each_folio_all

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: block: Fix iterating over an empty bio with bio_for_each_folio_all If the bio contains no data, bio_first_folio() calls page_folio() on a NULL pointer and oopses. Move the test that we've reached the end of the bio from bio_next_folio() to bio_first_folio(). [axboe: add unlikely() to error case]

References

• https://git.kernel.org/stable/c/c6350b5cb78e9024c49eaee6fdb914ad2903a5fe
• https://git.kernel.org/stable/c/a6bd8182137a12d22d3f2cee463271bdcb491659
• https://git.kernel.org/stable/c/ca3ede3f5893e2d26d4dbdef1eec28a8487fafde
• https://git.kernel.org/stable/c/7bed6f3d08b7af27b7015da8dc3acf2b9c1f21d7