fuse: initialize the flock flag in fuse_file on allocation
authorMateusz Jurczyk <mjurczyk@google.com>
Wed, 7 Jun 2017 10:26:49 +0000 (12:26 +0200)
committerMiklos Szeredi <mszeredi@redhat.com>
Fri, 9 Jun 2017 09:16:22 +0000 (11:16 +0200)
commit68227c03cba84a24faf8a7277d2b1a03c8959c2c
tree3f477053fd341d1a14da8b1e9408bdd2559c6c03
parent2ea659a9ef488125eb46da6eb571de5eae5c43f6
fuse: initialize the flock flag in fuse_file on allocation

Before the patch, the flock flag could remain uninitialized for the
lifespan of the fuse_file allocation. Unless set to true in
fuse_file_flock(), it would remain in an indeterminate state until read in
an if statement in fuse_release_common(). This could consequently lead to
taking an unexpected branch in the code.

The bug was discovered by a runtime instrumentation designed to detect use
of uninitialized memory in the kernel.

Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com>
Fixes: 37fb3a30b462 ("fuse: fix flock")
Cc: <stable@vger.kernel.org> # v3.1+
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
fs/fuse/file.c