Commits
Masami Ichikawa committed 93518dd2eba
sysfs: Fix memory leak in sysfs_sd_setsecdata(). This patch fixies follwing two memory leak patterns that reported by kmemleak. sysfs_sd_setsecdata() is called during sys_lsetxattr() operation. It checks sd->s_iattr is NULL or not. Then if it is NULL, it calls sysfs_init_inode_attrs() to allocate memory. That code is this. iattrs = sd->s_iattr; if (!iattrs) iattrs = sysfs_init_inode_attrs(sd); The iattrs recieves sysfs_init_inode_attrs()'s result, but sd->s_iattr doesn't know the address. so it needs to set correct address to sd->s_iattr to free memory in other function. unreferenced object 0xffff880250b73e60 (size 32): comm "systemd", pid 1, jiffies 4294683888 (age 94.553s) hex dump (first 32 bytes): 73 79 73 74 65 6d 5f 75 3a 6f 62 6a 65 63 74 5f system_u:object_ 72 3a 73 79 73 66 73 5f 74 3a 73 30 00 00 00 00 r:sysfs_t:s0.... backtrace: [<ffffffff814cb1d0>] kmemleak_alloc+0x73/0x98 [<ffffffff811270ab>] __kmalloc+0x100/0x12c [<ffffffff8120775a>] context_struct_to_string+0x106/0x210 [<ffffffff81207cc1>] security_sid_to_context_core+0x10b/0x129 [<ffffffff812090ef>] security_sid_to_context+0x10/0x12 [<ffffffff811fb0da>] selinux_inode_getsecurity+0x7d/0xa8 [<ffffffff811fb127>] selinux_inode_getsecctx+0x22/0x2e [<ffffffff811f4d62>] security_inode_getsecctx+0x16/0x18 [<ffffffff81191dad>] sysfs_setxattr+0x96/0x117 [<ffffffff811542f0>] __vfs_setxattr_noperm+0x73/0xd9 [<ffffffff811543d9>] vfs_setxattr+0x83/0xa1 [<ffffffff811544c6>] setxattr+0xcf/0x101 [<ffffffff81154745>] sys_lsetxattr+0x6a/0x8f [<ffffffff814efda9>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff unreferenced object 0xffff88024163c5a0 (size 96): comm "systemd", pid 1, jiffies 4294683888 (age 94.553s) hex dump (first 32 bytes): 00 00 00 00 ed 41 00 00 00 00 00 00 00 00 00 00 .....A.......... 00 00 00 00 00 00 00 00 0c 64 42 4f 00 00 00 00 .........dBO.... backtrace: [<ffffffff814cb1d0>] kmemleak_alloc+0x73/0x98 [<ffffffff81127402>] kmem_cache_alloc_trace+0xc4/0xee [<ffffffff81191cbe>] sysfs_init_inode_attrs+0x2a/0x83 [<ffffffff81191dd6>] sysfs_setxattr+0xbf/0x117 [<ffffffff811542f0>] __vfs_setxattr_noperm+0x73/0xd9 [<ffffffff811543d9>] vfs_setxattr+0x83/0xa1 [<ffffffff811544c6>] setxattr+0xcf/0x101 [<ffffffff81154745>] sys_lsetxattr+0x6a/0x8f [<ffffffff814efda9>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff ` Signed-off-by: Masami Ichikawa <masami256@gmail.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>