[PATCH v4 2/5] kernel/pid.c: implement additional checks upon pidfd_create() parameters

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



By adding the pidfd_create() declaration to linux/pid.h, we
effectively expose this function to the rest of the kernel. In order
to avoid any unintended behavior, or set false expectations upon this
function, ensure that constraints are forced upon each of the passed
parameters. This includes the checking of whether the passed struct
pid is a thread-group leader as pidfd creation is currently limited to
such pid types.

Signed-off-by: Matthew Bobrowski <repnop@xxxxxxxxxx>
Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
---
 kernel/pid.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/kernel/pid.c b/kernel/pid.c
index d3cd95b8b080..efe87db44683 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -559,6 +559,12 @@ int pidfd_create(struct pid *pid, unsigned int flags)
 {
 	int fd;
 
+	if (!pid || !pid_has_task(pid, PIDTYPE_TGID))
+		return -EINVAL;
+
+	if (flags & ~(O_NONBLOCK | O_RDWR | O_CLOEXEC))
+		return -EINVAL;
+
 	fd = anon_inode_getfd("[pidfd]", &pidfd_fops, get_pid(pid),
 			      flags | O_RDWR | O_CLOEXEC);
 	if (fd < 0)
@@ -598,10 +604,7 @@ SYSCALL_DEFINE2(pidfd_open, pid_t, pid, unsigned int, flags)
 	if (!p)
 		return -ESRCH;
 
-	if (pid_has_task(p, PIDTYPE_TGID))
-		fd = pidfd_create(p, flags);
-	else
-		fd = -EINVAL;
+	fd = pidfd_create(p, flags);
 
 	put_pid(p);
 	return fd;
-- 
2.32.0.605.g8dce9f2422-goog

/M



[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux