Messages in this thread | | | From | Linus Torvalds <> | Date | Tue, 12 Jun 2018 18:44:37 -0700 | Subject | Re: [GIT PULL] overflow updates (part 2) for v4.18-rc1 |
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On Tue, Jun 12, 2018 at 4:36 PM Kees Cook <keescook@chromium.org> wrote: > > - Treewide conversions of allocators to use either 2-factor argument > variant when available, or array_size() and array3_size() as needed (Kees)
Ok, some of this smells just a tad too much of automation, but I've done the pull and it's going through my build tests.
Example nonsensical conversion:
- res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL); + res = kcalloc(2, sizeof(struct resource), GFP_KERNEL);
which isn't _wrong_, but...
In some of the cases it turns a compile-time constant into a function call, ie this just makes for bigger and slower code for no reason what-so-ever.
- ch->tx_array = vzalloc(MIC_DMA_DESC_RX_SIZE * sizeof(*ch->tx_array)); + ch->tx_array = vzalloc(array_size(MIC_DMA_DESC_RX_SIZE, + sizeof(*ch->tx_array)));
At least in the kzalloc/kcalloc conversion it results in more legible code.
The array_size() conversions, in contrast, actually result in *LESS* legible code, in worse code generation, and absolutely no upside for cases like the above.
To make up for it, there's some conversions *away* from nonsensical expressions:
- hc_name = kzalloc(sizeof(char) * (HSMMC_NAME_LEN + 1), GFP_KERNEL); + hc_name = kzalloc(HSMMC_NAME_LEN + 1, GFP_KERNEL);
but I _really_ think you were way too eager to move to array_size() even when it made no sense what-so-ever.
But at least with the kcalloc()/kmalloc_array() conversions now preferred, those crazy cases are now a minority rather than "most of the patch makes code worse".
I am *not* looking forward to the conflicts this causes, but maybe it won't be too bad. Fingers crossed.
Linus
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