Messages in this thread | | | Subject | Re: [PATCH v3 0/4] uaccess: Add unsafe accessors for arm64 | From | Julien Thierry <> | Date | Wed, 30 Jan 2019 16:17:00 +0000 |
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Hi,
Gentle ping for patches 3 and 4.
Thanks,
Julien
On 15/01/2019 13:58, Julien Thierry wrote: > Hi, > > First version of this series[1] was briefly in linux-next but had to be > reverted due to a bug where schedule would end up being called while > user_access was active[2]. > > After clarifications[3], rescheduling while in a user_access region is not > allowed. > > * Patches 1 and 2 implement the unsafe accessors for arm64 > * Patches 3 and 4 clarify this restriction in the API and attempts to > check against violations of the restriction. > > Changes since v2[4]: > - Rebase on v5.0-rc2 > - access_ok() is now done in user_access_begin(), so rework accessors > so access_ok() is not called in unsafe_get/put_user() > - Split addition of unsafe accessors and the user_access_region check > into separate patches > - Avoid reading SCTLR_EL1 in user_access_region check > - Add build option for user_access_region checking > - Reword clarifications on unsafe accessors API > > Changes since v1[1]: > - Add a way to detect code calling schedule within a user_access region > - Make sure put_user/get_user arguments are evaluated before disabling PAN > > [1] https://www.spinics.net/lists/arm-kernel/msg674925.html > [2] https://patchwork.kernel.org/patch/10634783/ > [3] https://lkml.org/lkml/2018/11/28/50 > [4] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-December/617080.html > > Cheers, > > Julien > > --> > > Julien Thierry (4): > arm64: uaccess: Cleanup get/put_user() > arm64: uaccess: Implement unsafe accessors > uaccess: Check no rescheduling function is called in unsafe region > arm64: uaccess: Implement user_access_region_active > > arch/arm64/include/asm/sysreg.h | 2 + > arch/arm64/include/asm/uaccess.h | 123 ++++++++++++++++++++++++++------------- > include/linux/kernel.h | 11 +++- > include/linux/uaccess.h | 13 +++++ > kernel/sched/core.c | 22 +++++++ > lib/Kconfig.debug | 8 +++ > 6 files changed, 135 insertions(+), 44 deletions(-) > > -- > 1.9.1 >
-- Julien Thierry
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