From: "sireesha.t" <sireesha.t@xxxxxxxxxxx> Leak is caused because smack_inode_getsecurity() is allocating memory using kstrdup(). Though the security_release_secctx() is called, it would not free the allocated memory. Calling security_release_secctx is not relevant for this scenario as inode_getsecurity() does not provide a "secctx". Similar fix has been mainlined: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?id=57e7ba04d422c3d41c8426380303ec9b7533ded9 The fix is to replace the security_release_secctx() with a kfree() Below is the KMEMLEAK dump: unreferenced object 0xffffffc025e11c80 (size 64): comm "systemd-tmpfile", pid 2452, jiffies 4294894464 (age 235587.492s) hex dump (first 32 bytes): 53 79 73 74 65 6d 3a 3a 53 68 61 72 65 64 00 00 System::Shared.. 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffff80081be770>] __save_stack_trace+0x28/0x34 [<ffffff80081bedb8>] create_object+0x130/0x25c [<ffffff80088c82f8>] kmemleak_alloc+0x30/0x5c [<ffffff80081b3ef0>] __kmalloc_track_caller+0x1cc/0x2a8 [<ffffff800818673c>] kstrdup+0x3c/0x6c [<ffffff80082d78b0>] smack_inode_getsecurity+0xcc/0xec [<ffffff80082d78f4>] smack_inode_getsecctx+0x24/0x44 [<ffffff80082d5ea0>] security_inode_getsecctx+0x50/0x70 [<ffffff800823bbcc>] kernfs_security_xattr_set+0x74/0xe0 [<ffffff80081eafec>] __vfs_setxattr+0x74/0x90 [<ffffff80081eb088>] __vfs_setxattr_noperm+0x80/0x1ac [<ffffff80081eb238>] vfs_setxattr+0x84/0xac [<ffffff80081eb374>] setxattr+0x114/0x178 [<ffffff80081eb44c>] path_setxattr+0x74/0xb8 [<ffffff80081ebdcc>] SyS_lsetxattr+0x10/0x1c [<ffffff800808310c>] __sys_trace_return+0x0/0x4 Signed-off-by: sireesha.t <sireesha.t@xxxxxxxxxxx> Signed-off-by: CHANDAN VN <chandan.vn@xxxxxxxxxxx> --- fs/kernfs/inode.c | 3 ++- fs/nfsd/nfs4xdr.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c index a343039..53befb8 100644 --- a/fs/kernfs/inode.c +++ b/fs/kernfs/inode.c @@ -369,7 +369,8 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler, mutex_unlock(&kernfs_mutex); if (secdata) - security_release_secctx(secdata, secdata_len); + kfree(secdata); + return error; } diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index aaa88c1..1e0dbe9 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2911,7 +2911,7 @@ static int get_parent_attributes(struct svc_export *exp, struct kstat *stat) out: #ifdef CONFIG_NFSD_V4_SECURITY_LABEL if (context) - security_release_secctx(context, contextlen); + kfree(context); #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */ kfree(acl); if (tempfh) { -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
