From 8fbf89a9669520ac09b3ae0013ff3eb34f8cab23 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 9 Jun 2023 17:29:15 +0100 Subject: [PATCH] linux-user: Return EINVAL for getgroups() with negative gidsetsize Coverity doesn't like the way we might end up calling getgroups() with a NULL grouplist pointer. This is fine for the special case of gidsetsize == 0, but we will also do it if the guest passes us a negative gidsetsize. (CID 1512465) Explicitly fail the negative gidsetsize with EINVAL, as the kernel does. This means we definitely only call the libc getgroups() with valid parameters. It also brings the getgroups() code in to line with the setgroups() code. Possibly Coverity may still complain about getgroups(0, NULL), but that would be a false positive. Signed-off-by: Peter Maydell Reviewed-by: Michael Tokarev Signed-off-by: Michael Tokarev --- linux-user/syscall.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 94256cc262..f2cb101d83 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -11676,7 +11676,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, g_autofree gid_t *grouplist = NULL; int i; - if (gidsetsize > NGROUPS_MAX) { + if (gidsetsize > NGROUPS_MAX || gidsetsize < 0) { return -TARGET_EINVAL; } if (gidsetsize > 0) { @@ -12012,7 +12012,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1, g_autofree gid_t *grouplist = NULL; int i; - if (gidsetsize > NGROUPS_MAX) { + if (gidsetsize > NGROUPS_MAX || gidsetsize < 0) { return -TARGET_EINVAL; } if (gidsetsize > 0) {