arm64: fix possible spectre-v1 write in ptrace_hbp_set_event()
[ Upstream commit 14d6e289a8
]
It's possible for userspace to control idx. Sanitize idx when using it
as an array index, to inhibit the potential spectre-v1 write gadget.
Found by smatch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pull/10/head
parent
991bad26b3
commit
c1e2aee995
|
@ -274,19 +274,22 @@ static int ptrace_hbp_set_event(unsigned int note_type,
|
|||
|
||||
switch (note_type) {
|
||||
case NT_ARM_HW_BREAK:
|
||||
if (idx < ARM_MAX_BRP) {
|
||||
tsk->thread.debug.hbp_break[idx] = bp;
|
||||
err = 0;
|
||||
}
|
||||
if (idx >= ARM_MAX_BRP)
|
||||
goto out;
|
||||
idx = array_index_nospec(idx, ARM_MAX_BRP);
|
||||
tsk->thread.debug.hbp_break[idx] = bp;
|
||||
err = 0;
|
||||
break;
|
||||
case NT_ARM_HW_WATCH:
|
||||
if (idx < ARM_MAX_WRP) {
|
||||
tsk->thread.debug.hbp_watch[idx] = bp;
|
||||
err = 0;
|
||||
}
|
||||
if (idx >= ARM_MAX_WRP)
|
||||
goto out;
|
||||
idx = array_index_nospec(idx, ARM_MAX_WRP);
|
||||
tsk->thread.debug.hbp_watch[idx] = bp;
|
||||
err = 0;
|
||||
break;
|
||||
}
|
||||
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in New Issue