kernel/linux.git/lib/iov_iter.c, branch v6.1.168

instrumented.h: allow instrumenting both sides of copy_from_user()

2022-10-03T21:03:18+00:00

Introduce instrument_copy_from_user_before() and instrument_copy_from_user_after() hooks to be invoked before and after the call to copy_from_user(). KASAN and KCSAN will be only using instrument_copy_from_user_before(), but for KMSAN we'll need to insert code after copy_from_user(). Link: https://lkml.kernel.org/r/20220915150417.722975-4-glider@google.com Signed-off-by: Alexander Potapenko Reviewed-by: Marco Elver Cc: Alexander Viro Cc: Alexei Starovoitov Cc: Andrey Konovalov Cc: Andrey Konovalov Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Christoph Hellwig Cc: Christoph Lameter Cc: David Rientjes Cc: Dmitry Vyukov Cc: Eric Biggers Cc: Eric Biggers Cc: Eric Dumazet Cc: Greg Kroah-Hartman Cc: Herbert Xu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: Jens Axboe Cc: Joonsoo Kim Cc: Kees Cook Cc: Mark Rutland Cc: Matthew Wilcox Cc: Michael S. Tsirkin Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Petr Mladek Cc: Stephen Rothwell Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vegard Nossum Cc: Vlastimil Babka Signed-off-by: Andrew Morton

fix copy_page_from_iter() for compound destinations

2022-08-09T02:37:26+00:00

had been broken for ITER_BVEC et.al. since ever (OK, v3.17 when ITER_BVEC had first appeared)... Signed-off-by: Al Viro

copy_page_to_iter(): don't split high-order page in case of ITER_PIPE

2022-08-09T02:37:25+00:00

... just shove it into one pipe_buffer. Signed-off-by: Al Viro

expand those iov_iter_advance()...

2022-08-09T02:37:25+00:00

Signed-off-by: Al Viro

pipe_get_pages(): switch to append_pipe()

2022-08-09T02:37:25+00:00

now that we are advancing the iterator, there's no need to treat the first page separately - just call append_pipe() in a loop. Signed-off-by: Al Viro

get rid of non-advancing variants

2022-08-09T02:37:24+00:00

mechanical change; will be further massaged in subsequent commits Reviewed-by: Jeff Layton Signed-off-by: Al Viro

iov_iter: saner helper for page array allocation

2022-08-09T02:37:22+00:00

All call sites of get_pages_array() are essenitally identical now. Replace with common helper... Returns number of slots available in resulting array or 0 on OOM; it's up to the caller to make sure it doesn't ask to zero-entry array (i.e. neither maxpages nor size are allowed to be zero). Reviewed-by: Jeff Layton Signed-off-by: Al Viro

fold __pipe_get_pages() into pipe_get_pages()

2022-08-09T02:37:21+00:00

... and don't mangle maxsize there - turn the loop into counting one instead. Easier to see that we won't run out of array that way. Note that special treatment of the partial buffer in that thing is an artifact of the non-advancing semantics of iov_iter_get_pages() - if not for that, it would be append_pipe(), same as the body of the loop that follows it. IOW, once we make iov_iter_get_pages() advancing, the whole thing will turn into calculate how many pages do we want allocate an array (if needed) call append_pipe() that many times. Reviewed-by: Jeff Layton Signed-off-by: Al Viro

ITER_XARRAY: don't open-code DIV_ROUND_UP()

2022-08-09T02:37:21+00:00

Reviewed-by: Jeff Layton Signed-off-by: Al Viro

unify the rest of iov_iter_get_pages()/iov_iter_get_pages_alloc() guts

2022-08-09T02:37:21+00:00

same as for pipes and xarrays; after that iov_iter_get_pages() becomes a wrapper for __iov_iter_get_pages_alloc(). Signed-off-by: Al Viro