From: Dave Martin Dave.Martin@arm.com
This patch has been added to the stable tree. If you have any objections, please let us know.
===============
[ Upstream commit 5fe81fe98123ce41265c65e95d34418d30d005d1 ]
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill TXSTATUS, a well-defined default value is used, based on the task's current value.
Suggested-by: James Hogan james.hogan@imgtec.com Signed-off-by: Dave Martin Dave.Martin@arm.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- arch/metag/kernel/ptrace.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/arch/metag/kernel/ptrace.c b/arch/metag/kernel/ptrace.c index ae659ba61948..2e4dfc15abd3 100644 --- a/arch/metag/kernel/ptrace.c +++ b/arch/metag/kernel/ptrace.c @@ -24,6 +24,16 @@ * user_regset definitions. */
+static unsigned long user_txstatus(const struct pt_regs *regs) +{ + unsigned long data = (unsigned long)regs->ctx.Flags; + + if (regs->ctx.SaveMask & TBICTX_CBUF_BIT) + data |= USER_GP_REGS_STATUS_CATCH_BIT; + + return data; +} + int metag_gp_regs_copyout(const struct pt_regs *regs, unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf) @@ -62,9 +72,7 @@ int metag_gp_regs_copyout(const struct pt_regs *regs, if (ret) goto out; /* TXSTATUS */ - data = (unsigned long)regs->ctx.Flags; - if (regs->ctx.SaveMask & TBICTX_CBUF_BIT) - data |= USER_GP_REGS_STATUS_CATCH_BIT; + data = user_txstatus(regs); ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &data, 4*25, 4*26); if (ret) @@ -119,6 +127,7 @@ int metag_gp_regs_copyin(struct pt_regs *regs, if (ret) goto out; /* TXSTATUS */ + data = user_txstatus(regs); ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &data, 4*25, 4*26); if (ret)