From cb6ec2f0e50eed9d13ddb258139fa8ee6bac7715 Mon Sep 17 00:00:00 2001 From: Steve Dickson Date: Tue, 17 Jul 2018 15:09:37 -0400 Subject: [PATCH] rpc.gssd: truncates 32-bit UIDs/GIDs to 16 bits architectures. utils/gssd_proc.c uses SYS_setresuid and SYS_setresgid in change_identity when it should use SYS_setresuid32 and SYS_setresgid32 instead. This causes it to truncate UIDs/GIDs > 65536. Fixes: https://bugs.launchpad.net/ubuntu/+source/nfs-utils/+bug/1779962 Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1595927 Signed-off-by: Steve Dickson --- utils/gssd/gssd_proc.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/utils/gssd/gssd_proc.c b/utils/gssd/gssd_proc.c index 8767e26..7a57c4e 100644 --- a/utils/gssd/gssd_proc.c +++ b/utils/gssd/gssd_proc.c @@ -434,6 +434,7 @@ static int change_identity(uid_t uid) { struct passwd *pw; + int res; /* drop list of supplimentary groups first */ if (syscall(SYS_setgroups, 0, 0) != 0) { @@ -459,14 +460,23 @@ change_identity(uid_t uid) * send a signal to all other threads to synchronize the uid in all * other threads. To bypass this, we have to call syscall() directly. */ - if (syscall(SYS_setresgid, pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) { +#ifdef __NR_setresuid32 + res = syscall(SYS_setresgid32, pw->pw_gid, pw->pw_gid, pw->pw_gid); +#else + res = syscall(SYS_setresgid, pw->pw_gid, pw->pw_gid, pw->pw_gid); +#endif + if (res != 0) { printerr(0, "WARNING: failed to set gid to %u!\n", pw->pw_gid); return errno; } - if (syscall(SYS_setresuid, uid, uid, uid) != 0) { - printerr(0, "WARNING: Failed to setuid for user with uid %u\n", - uid); +#ifdef __NR_setresuid32 + res = syscall(SYS_setresuid32, uid, uid, uid); +#else + res = syscall(SYS_setresuid, uid, uid, uid); +#endif + if (res != 0) { + printerr(0, "WARNING: Failed to setuid for user with uid %u\n", uid); return errno; } -- 2.17.1