Eric Biggers 80f6e3080b fs-verity: fix signed integer overflow with i_size near S64_MAX ... If the file size is almost S64_MAX, the calculated number of Merkle tree levels exceeds FS_VERITY_MAX_LEVELS, causing FS_IOC_ENABLE_VERITY to fail. This is unintentional, since as the comment above the definition of FS_VERITY_MAX_LEVELS states, it is enough for over U64_MAX bytes of data using SHA-256 and 4K blocks. (Specifically, 4096*128**8 >= 2**64.) The bug is actually that when the number of blocks in the first level is calculated from i_size, there is a signed integer overflow due to i_size being signed. Fix this by treating i_size as unsigned. This was found by the new test "generic: test fs-verity EFBIG scenarios" (https://lkml.kernel.org/r/b1d116cd4d0ea74b9cd86f349c672021e005a75c.1631558495.git.boris@bur.io). This didn't affect ext4 or f2fs since those have a smaller maximum file size, but it did affect btrfs which allows files up to S64_MAX bytes. Reported-by: Boris Burkov <boris@bur.io> Fixes: 3fda4c617e ("fs-verity: implement FS_IOC_ENABLE_VERITY ioctl") Fixes: fd2d1acfca ("fs-verity: add the hook for file ->open()") Cc: <stable@vger.kernel.org> # v5.4+ Reviewed-by: Boris Burkov <boris@bur.io> Link: https://lore.kernel.org/r/20210916203424.113376-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>		2021-09-22 10:56:34 -07:00
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Kconfig	fsverity: relax build time dependency on CRYPTO_SHA256	2021-04-22 17:31:32 +10:00
Makefile	fs-verity: add FS_IOC_READ_VERITY_METADATA ioctl	2021-02-07 14:51:11 -08:00
enable.c	fs-verity: fix signed integer overflow with i_size near S64_MAX	2021-09-22 10:56:34 -07:00
fsverity_private.h	fs-verity: don't pass whole descriptor to fsverity_verify_signature()	2021-02-07 14:51:09 -08:00
hash_algs.c	…
init.c	…
measure.c	…
open.c	fs-verity: fix signed integer overflow with i_size near S64_MAX	2021-09-22 10:56:34 -07:00
read_metadata.c	fs-verity: support reading signature with ioctl	2021-02-07 14:51:19 -08:00
signature.c	fs-verity: don't pass whole descriptor to fsverity_verify_signature()	2021-02-07 14:51:09 -08:00
verify.c	…