This is a note to let you know that I've just added the patch titled MIPS: Drop spurious __unused in struct compat_flock 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: mips-drop-spurious-__unused-in-struct-compat_flock.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. >From 6ae1756faddefd7494353380ee546dd38c2f97eb Mon Sep 17 00:00:00 2001 From: James Hogan <jhogan@xxxxxxxxxx> Date: Tue, 20 Feb 2018 15:44:37 +0000 Subject: MIPS: Drop spurious __unused in struct compat_flock From: James Hogan <jhogan@xxxxxxxxxx> commit 6ae1756faddefd7494353380ee546dd38c2f97eb upstream. MIPS' struct compat_flock doesn't match the 32-bit struct flock, as it has an extra short __unused before pad[4], which combined with alignment increases the size to 40 bytes compared with struct flock's 36 bytes. Since commit 8c6657cb50cb ("Switch flock copyin/copyout primitives to copy_{from,to}_user()"), put_compat_flock() writes the full compat_flock struct to userland, which results in corruption of the userland word after the struct flock when running 32-bit userlands on 64-bit kernels. This was observed to cause a bus error exception when starting Firefox on Debian 8 (Jessie). Reported-by: Peter Mamonov <pmamonov@xxxxxxxxx> Signed-off-by: James Hogan <jhogan@xxxxxxxxxx> Tested-by: Peter Mamonov <pmamonov@xxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> # 4.13+ Patchwork: https://patchwork.linux-mips.org/patch/18646/ Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/include/asm/compat.h | 1 - 1 file changed, 1 deletion(-) --- a/arch/mips/include/asm/compat.h +++ b/arch/mips/include/asm/compat.h @@ -86,7 +86,6 @@ struct compat_flock { compat_off_t l_len; s32 l_sysid; compat_pid_t l_pid; - short __unused; s32 pad[4]; }; Patches currently in stable-queue which might be from jhogan@xxxxxxxxxx are queue-4.14/mips-drop-spurious-__unused-in-struct-compat_flock.patch