From patchwork Sat Feb 2 23:04:48 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: linux-user: Support setgroups syscall with no groups Date: Sat, 02 Feb 2013 13:04:48 -0000 From: dillona@dillona.com X-Patchwork-Id: 217708 Message-Id: <1359846288-10053-1-git-send-email-dillona@dillona.com> To: qemu-devel@nongnu.org Cc: riku.voipio@iki.fi, Dillon Amburgey From: Dillon Amburgey Signed-off-by: Dillon Amburgey Reviewed-by: Peter Maydell --- linux-user/syscall.c | 22 ++++++++++++---------- 1 files changed, 12 insertions(+), 10 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index a148d9f..7344052 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -7653,18 +7653,20 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, { int gidsetsize = arg1; target_id *target_grouplist; - gid_t *grouplist; + gid_t *grouplist = NULL; int i; - - grouplist = alloca(gidsetsize * sizeof(gid_t)); - target_grouplist = lock_user(VERIFY_READ, arg2, gidsetsize * 2, 1); - if (!target_grouplist) { - ret = -TARGET_EFAULT; - goto fail; + if (gidsetsize) { + grouplist = alloca(gidsetsize * sizeof(gid_t)); + target_grouplist = lock_user(VERIFY_READ, arg2, gidsetsize * 2, 1); + if (!target_grouplist) { + ret = -TARGET_EFAULT; + goto fail; + } + for (i = 0; i < gidsetsize; i++) { + grouplist[i] = low2highgid(tswapid(target_grouplist[i])); + } + unlock_user(target_grouplist, arg2, 0); } - for(i = 0;i < gidsetsize; i++) - grouplist[i] = low2highgid(tswapid(target_grouplist[i])); - unlock_user(target_grouplist, arg2, 0); ret = get_errno(setgroups(gidsetsize, grouplist)); } break;