powerpc/signal32: Perform access_ok() inside restore_user_regs()

In preparation of using user_access_begin/end in restore_user_regs(),
move the access_ok() inside the function.

It makes no difference as the behaviour on a failed access_ok() is
the same as on failed restore_user_regs().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c106eb2f37c3040f1fd38b40e50c670feb7cb835.1616151715.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy 2021-03-19 11:06:55 +00:00 committed by Michael Ellerman
parent ca9e1605cd
commit 362471b319
1 changed files with 3 additions and 5 deletions

View File

@ -492,6 +492,8 @@ static long restore_user_regs(struct pt_regs *regs,
int i;
#endif
if (!access_ok(sr, sizeof(*sr)))
return 1;
/*
* restore general registers but not including MSR or SOFTE. Also
* take care of keeping r2 (TLS) intact if not a signal
@ -963,13 +965,10 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int
if (__get_user(cmcp, &ucp->uc_regs))
return -EFAULT;
mcp = (struct mcontext __user *)(u64)cmcp;
/* no need to check access_ok(mcp), since mcp < 4GB */
}
#else
if (__get_user(mcp, &ucp->uc_regs))
return -EFAULT;
if (!access_ok(mcp, sizeof(*mcp)))
return -EFAULT;
#endif
set_current_blocked(&set);
if (restore_user_regs(regs, mcp, sig))
@ -1362,8 +1361,7 @@ SYSCALL_DEFINE0(sigreturn)
} else {
sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
addr = sr;
if (!access_ok(sr, sizeof(*sr))
|| restore_user_regs(regs, sr, 1))
if (restore_user_regs(regs, sr, 1))
goto badframe;
}