kernel/linux.git/include/asm-generic/uaccess.h, branch v6.19.11

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

uaccess: remove CONFIG_SET_FS

2022-02-25T08:36:06+00:00

There are no remaining callers of set_fs(), so CONFIG_SET_FS can be removed globally, along with the thread_info field and any references to it. This turns access_ok() into a cheaper check against TASK_SIZE_MAX. As CONFIG_SET_FS is now gone, drop all remaining references to set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel(). Acked-by: Sam Ravnborg # for sparc32 changes Acked-by: "Eric W. Biederman" Tested-by: Sergey Matyukevich # for arc changes Acked-by: Stafford Horne # [openrisc, asm-generic] Acked-by: Dinh Nguyen Signed-off-by: Arnd Bergmann

uaccess: generalize access_ok()

2022-02-25T08:36:05+00:00

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 Acked-by: Mark Rutland [arm64, asm-generic] Acked-by: Geert Uytterhoeven Acked-by: Stafford Horne Acked-by: Dinh Nguyen Signed-off-by: Arnd Bergmann

uaccess: add generic __{get,put}_kernel_nofault

2022-02-25T08:36:05+00:00

Nine architectures are still missing __{get,put}_kernel_nofault: alpha, ia64, microblaze, nds32, nios2, openrisc, sh, sparc32, xtensa. Add a generic version that lets everything use the normal copy_{from,to}_kernel_nofault() code based on these, removing the last use of get_fs()/set_fs() from architecture-independent code. Reviewed-by: Christoph Hellwig Acked-by: Geert Uytterhoeven Signed-off-by: Arnd Bergmann

asm-generic: uaccess: remove inline strncpy_from_user/strnlen_user

2021-07-27T21:01:13+00:00

The inline version is used on three NOMMU architectures and is particularly inefficient when it scans the string one byte at a time twice. It also lacks a check for user_addr_max(), but this is probably ok on NOMMU targets. Consolidate the asm-generic implementation with the library version that is used everywhere else. This version is generalized enough to work efficiently on both MMU and NOMMU targets, and using the same code everywhere reduces the potential for subtle bugs. Mark the prototypes as __must_check in the process. Reviewed-by: Geert Uytterhoeven Acked-by: Geert Uytterhoeven Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann

asm-generic/uaccess.h: remove __strncpy_from_user/__strnlen_user

2021-07-23T12:39:56+00:00

This is a preparation for changing over architectures to the generic implementation one at a time. As there are no callers of either __strncpy_from_user() or __strnlen_user(), fold these into the strncpy_from_user() and strnlen_user() functions to make each implementation independent of the others. Many of these implementations have known bugs, but the intention here is to not change behavior at all and stay compatible with those bugs for the moment. Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann

asm-generic: uaccess: 1-byte access is always aligned

2021-05-17T11:30:29+00:00

With the cleaned up version of asm-generic/unaligned.h, there is a warning about the get_user/put_user helpers using unaligned access for single-byte variables: include/asm-generic/uaccess.h: In function ‘__get_user_fn’: include/asm-generic/unaligned.h:13:15: warning: ‘packed’ attribute ignored for field of type ‘u8’ {aka ‘unsigned char’} [-Wattributes] const struct { type x __packed; } *__pptr = (typeof(__pptr))(ptr); \ Change these to use a direct pointer dereference to avoid the warnings. Signed-off-by: Arnd Bergmann

asm-generic: mark __{get,put}_user_fn as __always_inline

2020-10-27T15:13:09+00:00

Without the explicit __always_inline, some RISC-V configs place the functions out of line, triggering the BUILD_BUG_ON checks in the function. Fixes: 11129e8ed4d9 ("riscv: use memcpy based uaccess for nommu again") Reported-by: kernel test robot Signed-off-by: Christoph Hellwig Signed-off-by: Arnd Bergmann

asm-generic: make the set_fs implementation optional

2020-10-04T17:27:02+00:00

Put all the set_fs related code under CONFIG_SET_FS so that asm-generic/uaccess.h can be used for set_fs-less builds. Signed-off-by: Christoph Hellwig Acked-by: Arnd Bergmann Signed-off-by: Palmer Dabbelt

asm-generic: add nommu implementations of __{get,put}_kernel_nofault

2020-10-04T17:26:57+00:00

Add native implementations of __{get,put}_kernel_nofault using {get,put}_unaligned, just like the {get,put}_user implementations. Signed-off-by: Christoph Hellwig Acked-by: Arnd Bergmann Signed-off-by: Palmer Dabbelt