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12700c17fc
There are many different ways that access_ok() is defined across architectures, but in the end, they all just compare against the user_addr_max() value or they accept anything. Provide one definition that works for most architectures, checking against TASK_SIZE_MAX for user processes or skipping the check inside of uaccess_kernel() sections. For architectures without CONFIG_SET_FS(), this should be the fastest check, as it comes down to a single comparison of a pointer against a compile-time constant, while the architecture specific versions tend to do something more complex for historic reasons or get something wrong. Type checking for __user annotations is handled inconsistently across architectures, but this is easily simplified as well by using an inline function that takes a 'const void __user *' argument. A handful of callers need an extra __user annotation for this. Some architectures had trick to use 33-bit or 65-bit arithmetic on the addresses to calculate the overflow, however this simpler version uses fewer registers, which means it can produce better object code in the end despite needing a second (statically predicted) branch. Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> |
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| alchemy | ||
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| ath79 | ||
| bcm47xx | ||
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| bmips | ||
| boot | ||
| cavium-octeon | ||
| cobalt | ||
| configs | ||
| crypto | ||
| dec | ||
| fw | ||
| generic | ||
| include | ||
| ingenic | ||
| jazz | ||
| kernel | ||
| kvm | ||
| lantiq | ||
| lib | ||
| loongson2ef | ||
| loongson32 | ||
| loongson64 | ||
| math-emu | ||
| mm | ||
| mti-malta | ||
| n64 | ||
| net | ||
| pci | ||
| pic32 | ||
| power | ||
| ralink | ||
| rb532 | ||
| sgi-ip22 | ||
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| sgi-ip32 | ||
| sibyte | ||
| sni | ||
| tools | ||
| txx9 | ||
| vdso | ||
| vr41xx | ||
| Kbuild | ||
| Kbuild.platforms | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| Makefile.postlink | ||