5.10-stable review patch. If anyone has any objections, please let me know.
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From: Sean Young sean@mess.org
commit 6a9d552483d50953320b9d3b57abdee8d436f23f upstream.
Note that bpf attach/detach also requires CAP_NET_ADMIN.
Cc: stable@vger.kernel.org Signed-off-by: Sean Young sean@mess.org Signed-off-by: Mauro Carvalho Chehab mchehab@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/rc/bpf-lirc.c | 6 +++--- drivers/media/rc/lirc_dev.c | 5 ++++- drivers/media/rc/rc-core-priv.h | 2 +- 3 files changed, 8 insertions(+), 5 deletions(-)
--- a/drivers/media/rc/bpf-lirc.c +++ b/drivers/media/rc/bpf-lirc.c @@ -249,7 +249,7 @@ int lirc_prog_attach(const union bpf_att if (attr->attach_flags) return -EINVAL;
- rcdev = rc_dev_get_from_fd(attr->target_fd); + rcdev = rc_dev_get_from_fd(attr->target_fd, true); if (IS_ERR(rcdev)) return PTR_ERR(rcdev);
@@ -274,7 +274,7 @@ int lirc_prog_detach(const union bpf_att if (IS_ERR(prog)) return PTR_ERR(prog);
- rcdev = rc_dev_get_from_fd(attr->target_fd); + rcdev = rc_dev_get_from_fd(attr->target_fd, true); if (IS_ERR(rcdev)) { bpf_prog_put(prog); return PTR_ERR(rcdev); @@ -299,7 +299,7 @@ int lirc_prog_query(const union bpf_attr if (attr->query.query_flags) return -EINVAL;
- rcdev = rc_dev_get_from_fd(attr->query.target_fd); + rcdev = rc_dev_get_from_fd(attr->query.target_fd, false); if (IS_ERR(rcdev)) return PTR_ERR(rcdev);
--- a/drivers/media/rc/lirc_dev.c +++ b/drivers/media/rc/lirc_dev.c @@ -826,7 +826,7 @@ void __exit lirc_dev_exit(void) unregister_chrdev_region(lirc_base_dev, RC_DEV_MAX); }
-struct rc_dev *rc_dev_get_from_fd(int fd) +struct rc_dev *rc_dev_get_from_fd(int fd, bool write) { struct fd f = fdget(fd); struct lirc_fh *fh; @@ -840,6 +840,9 @@ struct rc_dev *rc_dev_get_from_fd(int fd return ERR_PTR(-EINVAL); }
+ if (write && !(f.file->f_mode & FMODE_WRITE)) + return ERR_PTR(-EPERM); + fh = f.file->private_data; dev = fh->rc;
--- a/drivers/media/rc/rc-core-priv.h +++ b/drivers/media/rc/rc-core-priv.h @@ -325,7 +325,7 @@ void lirc_raw_event(struct rc_dev *dev, void lirc_scancode_event(struct rc_dev *dev, struct lirc_scancode *lsc); int lirc_register(struct rc_dev *dev); void lirc_unregister(struct rc_dev *dev); -struct rc_dev *rc_dev_get_from_fd(int fd); +struct rc_dev *rc_dev_get_from_fd(int fd, bool write); #else static inline int lirc_dev_init(void) { return 0; } static inline void lirc_dev_exit(void) {}