Will Deacon 6e693b3ffe x86: uaccess: Inhibit speculation past access_ok() in user_access_begin() ... Commit 594cc251fd ("make 'user_access_begin()' do 'access_ok()'") makes the access_ok() check part of the user_access_begin() preceding a series of 'unsafe' accesses. This has the desirable effect of ensuring that all 'unsafe' accesses have been range-checked, without having to pick through all of the callsites to verify whether the appropriate checking has been made. However, the consolidated range check does not inhibit speculation, so it is still up to the caller to ensure that they are not susceptible to any speculative side-channel attacks for user addresses that ultimately fail the access_ok() check. This is an oversight, so use __uaccess_begin_nospec() to ensure that speculation is inhibited until the access_ok() check has passed. Reported-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2019-01-20 15:33:22 +12:00
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asm	x86: uaccess: Inhibit speculation past access_ok() in user_access_begin()	2019-01-20 15:33:22 +12:00
uapi/asm	arch: remove redundant UAPI generic-y defines	2019-01-06 10:22:15 +09:00