diff options
Diffstat (limited to 'fs/autofs4/waitq.c')
| -rw-r--r-- | fs/autofs4/waitq.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 2341375386f8..136a0d6914c6 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -90,7 +90,24 @@ static int autofs4_write(struct file *file, const void *addr, int bytes) return (bytes > 0); } - + +/* + * The autofs_v5 packet was misdesigned. + * + * The packets are identical on x86-32 and x86-64, but have different + * alignment. Which means that 'sizeof()' will give different results. + * Fix it up for the case of running 32-bit user mode on a 64-bit kernel. + */ +static noinline size_t autofs_v5_packet_size(struct autofs_sb_info *sbi) +{ + size_t pktsz = sizeof(struct autofs_v5_packet); +#if defined(CONFIG_X86_64) && defined(CONFIG_COMPAT) + if (sbi->compat_daemon > 0) + pktsz -= 4; +#endif + return pktsz; +} + static void autofs4_notify_daemon(struct autofs_sb_info *sbi, struct autofs_wait_queue *wq, int type) @@ -147,8 +164,7 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi, { struct autofs_v5_packet *packet = &pkt.v5_pkt.v5_packet; - pktsz = sizeof(*packet); - + pktsz = autofs_v5_packet_size(sbi); packet->wait_queue_token = wq->wait_queue_token; packet->len = wq->name.len; memcpy(packet->name, wq->name.name, wq->name.len); |