kernel/linux.git/include/linux, branch v5.15.38

mtd: fix 'part' field data corruption in mtd_info

2022-05-09T07:14:34+00:00

[ Upstream commit 37c5f9e80e015d0df17d0c377c18523002986851 ] Commit 46b5889cc2c5 ("mtd: implement proper partition handling") started using "mtd_get_master_ofs()" in mtd callbacks to determine memory offsets by means of 'part' field from mtd_info, what previously was smashed accessing 'master' field in the mtd_set_dev_defaults() method. That provides wrong offset what causes hardware access errors. Just make 'part', 'master' as separate fields, rather than using union type to avoid 'part' data corruption when mtd_set_dev_defaults() is called. Fixes: 46b5889cc2c5 ("mtd: implement proper partition handling") Signed-off-by: Oleksandr Ocheretnyi Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/20220417184649.449289-1-oocheret@cisco.com Signed-off-by: Sasha Levin

hex2bin: make the function hex_to_bin constant-time

2022-05-09T07:14:30+00:00

commit e5be15767e7e284351853cbaba80cde8620341fb upstream. The function hex2bin is used to load cryptographic keys into device mapper targets dm-crypt and dm-integrity. It should take constant time independent on the processed data, so that concurrently running unprivileged code can't infer any information about the keys via microarchitectural convert channels. This patch changes the function hex_to_bin so that it contains no branches and no memory accesses. Note that this shouldn't cause performance degradation because the size of the new function is the same as the size of the old function (on x86-64) - and the new function causes no branch misprediction penalties. I compile-tested this function with gcc on aarch64 alpha arm hppa hppa64 i386 ia64 m68k mips32 mips64 powerpc powerpc64 riscv sh4 s390x sparc32 sparc64 x86_64 and with clang on aarch64 arm hexagon i386 mips32 mips64 powerpc powerpc64 s390x sparc32 sparc64 x86_64 to verify that there are no branches in the generated code. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

iov_iter: Introduce nofault flag to disable page faults

2022-05-01T15:22:33+00:00

commit 3337ab08d08b1a375f88471d9c8b1cac968cb054 upstream Introduce a new nofault flag to indicate to iov_iter_get_pages not to fault in user pages. This is implemented by passing the FOLL_NOFAULT flag to get_user_pages, which causes get_user_pages to fail when it would otherwise fault in a page. We'll use the ->nofault flag to prevent iomap_dio_rw from faulting in pages when page faults are not allowed. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

gup: Introduce FOLL_NOFAULT flag to disable page faults

2022-05-01T15:22:32+00:00

commit 55b8fe703bc51200d4698596c90813453b35ae63 upstream Introduce a new FOLL_NOFAULT flag that causes get_user_pages to return -EFAULT when it would otherwise trigger a page fault. This is roughly similar to FOLL_FAST_ONLY but available on all architectures, and less fragile. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

iomap: Add done_before argument to iomap_dio_rw

2022-05-01T15:22:32+00:00

commit 4fdccaa0d184c202f98d73b24e3ec8eeee88ab8d upstream Add a done_before argument to iomap_dio_rw that indicates how much of the request has already been transferred. When the request succeeds, we report that done_before additional bytes were tranferred. This is useful for finishing a request asynchronously when part of the request has already been completed synchronously. We'll use that to allow iomap_dio_rw to be used with page faults disabled: when a page fault occurs while submitting a request, we synchronously complete the part of the request that has already been submitted. The caller can then take care of the page fault and call iomap_dio_rw again for the rest of the request, passing in the number of bytes already tranferred. Signed-off-by: Andreas Gruenbacher Reviewed-by: Darrick J. Wong Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

iomap: Support partial direct I/O on user copy failures

2022-05-01T15:22:31+00:00

commit 97308f8b0d867e9ef59528cd97f0db55ffdf5651 upstream In iomap_dio_rw, when iomap_apply returns an -EFAULT error and the IOMAP_DIO_PARTIAL flag is set, complete the request synchronously and return a partial result. This allows the caller to deal with the page fault and retry the remainder of the request. Signed-off-by: Andreas Gruenbacher Reviewed-by: Darrick J. Wong Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

iov_iter: Introduce fault_in_iov_iter_writeable

2022-05-01T15:22:29+00:00

commit cdd591fc86e38ad3899196066219fbbd845f3162 upstream Introduce a new fault_in_iov_iter_writeable helper for safely faulting in an iterator for writing. Uses get_user_pages() to fault in the pages without actually writing to them, which would be destructive. We'll use fault_in_iov_iter_writeable in gfs2 once we've determined that the iterator passed to .read_iter isn't in memory. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable

2022-05-01T15:22:28+00:00

commit a6294593e8a1290091d0b078d5d33da5e0cd3dfe upstream Turn iov_iter_fault_in_readable into a function that returns the number of bytes not faulted in, similar to copy_to_user, instead of returning a non-zero value when any of the requested pages couldn't be faulted in. This supports the existing users that require all pages to be faulted in as well as new users that are happy if any pages can be faulted in. Rename iov_iter_fault_in_readable to fault_in_iov_iter_readable to make sure this change doesn't silently break things. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable}

2022-05-01T15:22:28+00:00

commit bb523b406c849eef8f265a07cd7f320f1f177743 upstream Turn fault_in_pages_{readable,writeable} into versions that return the number of bytes not faulted in, similar to copy_to_user, instead of returning a non-zero value when any of the requested pages couldn't be faulted in. This supports the existing users that require all pages to be faulted in as well as new users that are happy if any pages can be faulted in. Rename the functions to fault_in_{readable,writeable} to make sure this change doesn't silently break things. Neither of these functions is entirely trivial and it doesn't seem useful to inline them, so move them to mm/gup.c. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.

2022-05-01T15:22:26+00:00

commit 216e3cd2f28dbbf1fe86848e0e29e6693b9f0a20 upstream. Some helper functions may modify its arguments, for example, bpf_d_path, bpf_get_stack etc. Previously, their argument types were marked as ARG_PTR_TO_MEM, which is compatible with read-only mem types, such as PTR_TO_RDONLY_BUF. Therefore it's legitimate, but technically incorrect, to modify a read-only memory by passing it into one of such helper functions. This patch tags the bpf_args compatible with immutable memory with MEM_RDONLY flag. The arguments that don't have this flag will be only compatible with mutable memory types, preventing the helper from modifying a read-only memory. The bpf_args that have MEM_RDONLY are compatible with both mutable memory and immutable memory. Signed-off-by: Hao Luo Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211217003152.48334-9-haoluo@google.com Cc: stable@vger.kernel.org # 5.15.x Signed-off-by: Greg Kroah-Hartman