diff options
| author | Andy Lutomirski <[email protected]> | 2021-03-04 11:05:54 -0800 |
|---|---|---|
| committer | Borislav Petkov <[email protected]> | 2021-03-06 13:10:06 +0100 |
| commit | 5d5675df792ff67e74a500c4c94db0f99e6a10ef (patch) | |
| tree | e9b463d979b295c7f5f05efe5723937ad73aef65 | |
| parent | b59cc97674c947861783ca92b9a6e7d043adba96 (diff) | |
x86/entry: Fix entry/exit mismatch on failed fast 32-bit syscalls
On a 32-bit fast syscall that fails to read its arguments from user
memory, the kernel currently does syscall exit work but not
syscall entry work. This confuses audit and ptrace. For example:
$ ./tools/testing/selftests/x86/syscall_arg_fault_32
...
strace: pid 264258: entering, ptrace_syscall_info.op == 2
...
This is a minimal fix intended for ease of backporting. A more
complete cleanup is coming.
Fixes: 0b085e68f407 ("x86/entry: Consolidate 32/64 bit syscall entry")
Signed-off-by: Andy Lutomirski <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/8c82296ddf803b91f8d1e5eac89e5803ba54ab0e.1614884673.git.luto@kernel.org
| -rw-r--r-- | arch/x86/entry/common.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index a2433ae8a65e..4efd39aacb9f 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -128,7 +128,8 @@ static noinstr bool __do_fast_syscall_32(struct pt_regs *regs) regs->ax = -EFAULT; instrumentation_end(); - syscall_exit_to_user_mode(regs); + local_irq_disable(); + irqentry_exit_to_user_mode(regs); return false; } |