From 7e17916b35797396f681a3270245fd29c1e4c250 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sat, 3 Nov 2018 16:39:28 +0100 Subject: btrfs: avoid link error with CONFIG_NO_AUTO_INLINE Note: this patch fixes a problem in a feature outside of btrfs ("kernel hacking: add a config option to disable compiler auto-inlining") and is applied ahead of time due to cross-subsystem dependencies. On 32-bit ARM with gcc-8, I see a link error with the addition of the CONFIG_NO_AUTO_INLINE option: fs/btrfs/super.o: In function `btrfs_statfs': super.c:(.text+0x67b8): undefined reference to `__aeabi_uldivmod' super.c:(.text+0x67fc): undefined reference to `__aeabi_uldivmod' super.c:(.text+0x6858): undefined reference to `__aeabi_uldivmod' super.c:(.text+0x6920): undefined reference to `__aeabi_uldivmod' super.c:(.text+0x693c): undefined reference to `__aeabi_uldivmod' fs/btrfs/super.o:super.c:(.text+0x6958): more undefined references to `__aeabi_uldivmod' follow So far this is the only file that shows the behavior, so I'd propose to just work around it by marking the functions as 'static inline' that normally get inlined here. The reference to __aeabi_uldivmod comes from a div_u64() which has an optimization for a constant division that uses a straight '/' operator when the result should be known to the compiler. My interpretation is that as we turn off inlining, gcc still expects the result to be constant but fails to use that constant value. Link: https://lkml.kernel.org/r/20181103153941.1881966-1-arnd@arndb.de Reviewed-by: Nikolay Borisov Reviewed-by: Changbin Du Signed-off-by: Arnd Bergmann [ add the note ] Signed-off-by: David Sterba --- fs/btrfs/super.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/btrfs/super.c') diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index b362b45dd757..cbc9d0d2c12d 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1916,7 +1916,7 @@ restore: } /* Used to sort the devices by max_avail(descending sort) */ -static int btrfs_cmp_device_free_bytes(const void *dev_info1, +static inline int btrfs_cmp_device_free_bytes(const void *dev_info1, const void *dev_info2) { if (((struct btrfs_device_info *)dev_info1)->max_avail > @@ -1945,8 +1945,8 @@ static inline void btrfs_descending_sort_devices( * The helper to calc the free space on the devices that can be used to store * file data. */ -static int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info, - u64 *free_bytes) +static inline int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info, + u64 *free_bytes) { struct btrfs_device_info *devices_info; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; -- cgit From f505754fd6599230371cb01b9332754ddc104be1 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Wed, 14 Nov 2018 11:35:24 +0000 Subject: Btrfs: ensure path name is null terminated at btrfs_control_ioctl We were using the path name received from user space without checking that it is null terminated. While btrfs-progs is well behaved and does proper validation and null termination, someone could call the ioctl and pass a non-null terminated patch, leading to buffer overrun problems in the kernel. The ioctl is protected by CAP_SYS_ADMIN. So just set the last byte of the path to a null character, similar to what we do in other ioctls (add/remove/resize device, snapshot creation, etc). CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Anand Jain Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/super.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/btrfs/super.c') diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index cbc9d0d2c12d..645fc81e2a94 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -2237,6 +2237,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, vol = memdup_user((void __user *)arg, sizeof(*vol)); if (IS_ERR(vol)) return PTR_ERR(vol); + vol->name[BTRFS_PATH_NAME_MAX] = '\0'; switch (cmd) { case BTRFS_IOC_SCAN_DEV: -- cgit