4.9-stable review patch. If anyone has any objections, please let me know.
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From: YueHaibing yuehaibing@huawei.com
commit f612acfae86af7ecad754ae6a46019be9da05b8e upstream.
syzkaller report this: BUG: memory leak unreferenced object 0xffffc9000488d000 (size 9195520): comm "syz-executor.0", pid 2752, jiffies 4294787496 (age 18.757s) hex dump (first 32 bytes): ff ff ff ff ff ff ff ff a8 00 00 00 01 00 00 00 ................ 02 00 00 00 00 00 00 00 80 a1 7a c1 ff ff ff ff ..........z..... backtrace: [<000000000863775c>] __vmalloc_node mm/vmalloc.c:1795 [inline] [<000000000863775c>] __vmalloc_node_flags mm/vmalloc.c:1809 [inline] [<000000000863775c>] vmalloc+0x8c/0xb0 mm/vmalloc.c:1831 [<000000003f668111>] kernel_read_file+0x58f/0x7d0 fs/exec.c:924 [<000000002385813f>] kernel_read_file_from_fd+0x49/0x80 fs/exec.c:993 [<0000000011953ff1>] __do_sys_finit_module+0x13b/0x2a0 kernel/module.c:3895 [<000000006f58491f>] do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290 [<00000000ee78baf4>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<00000000241f889b>] 0xffffffffffffffff
It should goto 'out_free' lable to free allocated buf while kernel_read fails.
Fixes: 39d637af5aa7 ("vfs: forbid write access when reading a file into memory") Signed-off-by: YueHaibing yuehaibing@huawei.com Signed-off-by: Al Viro viro@zeniv.linux.org.uk Cc: Thibaut Sautereau thibaut@sautereau.fr Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/exec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/exec.c +++ b/fs/exec.c @@ -938,7 +938,7 @@ int kernel_read_file(struct file *file, i_size - pos); if (bytes < 0) { ret = bytes; - goto out; + goto out_free; }
if (bytes == 0)