This is a note to let you know that I've just added the patch titled binfmt_misc: fix shift-out-of-bounds in check_special_flags to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: binfmt_misc-fix-shift-out-of-bounds-in-check_special.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 036a4a953c0372c2da3c4618e38988a515c8e54a Author: Liu Shixin <liushixin2@xxxxxxxxxx> Date: Wed Nov 2 10:51:23 2022 +0800 binfmt_misc: fix shift-out-of-bounds in check_special_flags [ Upstream commit 6a46bf558803dd2b959ca7435a5c143efe837217 ] UBSAN reported a shift-out-of-bounds warning: left shift of 1 by 31 places cannot be represented in type 'int' Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8d/0xcf lib/dump_stack.c:106 ubsan_epilogue+0xa/0x44 lib/ubsan.c:151 __ubsan_handle_shift_out_of_bounds+0x1e7/0x208 lib/ubsan.c:322 check_special_flags fs/binfmt_misc.c:241 [inline] create_entry fs/binfmt_misc.c:456 [inline] bm_register_write+0x9d3/0xa20 fs/binfmt_misc.c:654 vfs_write+0x11e/0x580 fs/read_write.c:582 ksys_write+0xcf/0x120 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x34/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x4194e1 Since the type of Node's flags is unsigned long, we should define these macros with same type too. Signed-off-by: Liu Shixin <liushixin2@xxxxxxxxxx> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221102025123.1117184-1-liushixin2@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index 566296ce7ea8..c19bf5c2fbec 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -42,10 +42,10 @@ static LIST_HEAD(entries); static int enabled = 1; enum {Enabled, Magic}; -#define MISC_FMT_PRESERVE_ARGV0 (1 << 31) -#define MISC_FMT_OPEN_BINARY (1 << 30) -#define MISC_FMT_CREDENTIALS (1 << 29) -#define MISC_FMT_OPEN_FILE (1 << 28) +#define MISC_FMT_PRESERVE_ARGV0 (1UL << 31) +#define MISC_FMT_OPEN_BINARY (1UL << 30) +#define MISC_FMT_CREDENTIALS (1UL << 29) +#define MISC_FMT_OPEN_FILE (1UL << 28) typedef struct { struct list_head list;