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2018-10-23ubifs: Add helper functions for authentication supportSascha Hauer4-0/+722
This patch adds the various helper functions needed for authentication support. We need functions to hash nodes, to embed HMACs into a node and to compare hashes and HMACs. Most functions first check if this filesystem is authenticated and bail out early if not, which makes the functions safe to be called with disabled authentication. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Add separate functions to init/crc a nodeSascha Hauer2-15/+29
When adding authentication support we will embed a HMAC into some nodes. To prepare these nodes we have to first initialize the nodes, then add a HMAC and finally add a CRC. To accomplish this add separate ubifs_init_node/ubifs_crc_node functions. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Format changes for authentication supportSascha Hauer3-3/+50
This patch adds the changes to the on disk format needed for authentication support. We'll add: * a HMAC covering super block node * a HMAC covering the master node * a hash over the root index node to the master node * a hash over the LPT to the master node * a flag to the filesystem flag indicating the filesystem is authenticated * an authentication node necessary to authenticate the nodes written to the journal heads while they are written. * a HMAC of a well known message to the super block node to be able to check if the correct key is provided And finally, not visible in this patch, nevertheless explained here: * hashes over the referenced child nodes in each branch of a index node Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Store read superblock nodeSascha Hauer3-22/+8
The superblock node is read/modified/written several times throughout the UBIFS code. Instead of reading it from the device each time just keep a copy in memory and write back the modified copy when necessary. This patch helps for authentication support, here we not only have to read the superblock node, but also have to authenticate it, which is easier if we do it once during initialization. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Drop write_nodeSascha Hauer1-34/+5
write_node() is used only once and can easily be replaced with calls to ubifs_prepare_node()/write_head() which makes the code a bit shorter. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Implement ubifs_lpt_lookup using ubifs_pnode_lookupSascha Hauer1-18/+2
ubifs_lpt_lookup() starts by looking up the nth pnode in the LPT. We already have this functionality in ubifs_pnode_lookup(). Use this function rather than open coding its functionality. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Export pnode_lookup as ubifs_pnode_lookupSascha Hauer3-36/+37
ubifs_lpt_lookup could be implemented using pnode_lookup. To make that possible move pnode_lookup from lpt.c to lpt_commit.c. Rename it to ubifs_pnode_lookup since it's now exported. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Pass ubifs_zbranch to read_znode()Sascha Hauer1-5/+6
read_znode() takes len, lnum and offs arguments which the caller all extracts from the same struct ubifs_zbranch *. When adding authentication support we would have to add a pointer to a hash to the arguments which is also part of struct ubifs_zbranch. Pass the ubifs_zbranch * instead so that we do not have to add another argument. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Pass ubifs_zbranch to try_read_node()Sascha Hauer1-7/+7
try_read_node() takes len, lnum and offs arguments which the caller all extracts from the same struct ubifs_zbranch *. When adding authentication support we would have to add a pointer to a hash to the arguments which is also part of struct ubifs_zbranch. Pass the ubifs_zbranch * instead so that we do not have to add another argument. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-23ubifs: Refactor create_default_filesystem()Sascha Hauer1-48/+47
create_default_filesystem() allocates memory for a node, writes that node and frees the memory directly afterwards. With this patch we allocate memory for all nodes at the beginning of the function and free the memory at the end. This makes it easier to implement authentication support since with authentication support we'll need the contents of some nodes when creating other nodes. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-10-13ubifs: Fix WARN_ON logic in exit pathRichard Weinberger1-2/+2
ubifs_assert() is not WARN_ON(), so we have to invert the checks. Randy faced this warning with UBIFS being a module, since most users use UBIFS as builtin because UBIFS is the rootfs nobody noticed so far. :-( Including me. Reported-by: Randy Dunlap <rdunlap@infradead.org> Fixes: 54169ddd382d ("ubifs: Turn two ubifs_assert() into a WARN_ON()") Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20Revert "ubifs: xattr: Don't operate on deleted inodes"Richard Weinberger1-24/+0
This reverts commit 11a6fc3dc743e22fb50f2196ec55bee5140d3c52. UBIFS wants to assert that xattr operations are only issued on files with positive link count. The said patch made this operations return -ENOENT for unlinked files such that the asserts will no longer trigger. This was wrong since xattr operations are perfectly fine on unlinked files. Instead the assertions need to be fixed/removed. Cc: <stable@vger.kernel.org> Fixes: 11a6fc3dc743 ("ubifs: xattr: Don't operate on deleted inodes") Reported-by: Koen Vandeputte <koen.vandeputte@ncentric.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20ubifs: drop false positive assertionSascha Hauer1-1/+3
The following sequence triggers ubifs_assert(c, c->lst.taken_empty_lebs > 0); at the end of ubifs_remount_fs(): mount -t ubifs /dev/ubi0_0 /mnt echo 1 > /sys/kernel/debug/ubifs/ubi0_0/ro_error umount /mnt mount -t ubifs -o ro /dev/ubix_y /mnt mount -o remount,ro /mnt The resulting UBIFS assert failed in ubifs_remount_fs at 1878 (pid 161) is a false positive. In the case above c->lst.taken_empty_lebs has never been changed from its initial zero value. This will only happen when the deferred recovery is done. Fix this by doing the assertion only when recovery has been done already. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20ubifs: Check for name being NULL while mountingRichard Weinberger1-0/+3
The requested device name can be NULL or an empty string. Check for that and refuse to continue. UBIFS has to do this manually since we cannot use mount_bdev(), which checks for this condition. Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system") Reported-by: syzbot+38bd0f7865e5c6379280@syzkaller.appspotmail.com Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-24ubifs: Remove empty file.hRichard Weinberger1-0/+0
This empty file sneaked into the tree by mistake. Remove it. Fixes: 6eb61d587f45 ("ubifs: Pass struct ubifs_info to ubifs_assert()") Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Set default assert action to read-onlyRichard Weinberger1-0/+1
Traditionally UBIFS just reported a failed assertion and moved on. The drawback is that users will notice UBIFS bugs when it is too late, most of the time when it is no longer about to mount. This makes bug hunting problematic since valuable information from failing asserts is long gone when UBIFS is dead. The other extreme, panic'ing on a failing assert is also not worthwhile, we want users and developers give a chance to collect as much debugging information as possible if UBIFS hits an assert. Therefore go for the third option, switch to read-only mode when an assert fails. That way UBIFS will not write possible bad data to the MTD and gives users the chance to collect debugging information. Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Allow setting assert action as mount parameterRichard Weinberger3-0/+37
Expose our three options to userspace. Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Rework ubifs_assert()Richard Weinberger3-4/+42
With having access to struct ubifs_info in ubifs_assert() we can give more information when an assert is failing. By using ubifs_err() we can tell which UBIFS instance failed. Also multiple actions can be taken now. We support: - report: This is what UBIFS did so far, just report the failure and go on. - read-only: Switch to read-only mode. - panic: shoot the kernel in the head. Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Pass struct ubifs_info to ubifs_assert()Richard Weinberger31-521/+550
This allows us to have more context in ubifs_assert() and take different actions depending on the configuration. Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Turn two ubifs_assert() into a WARN_ON()Richard Weinberger1-2/+2
We are going to pass struct ubifs_info to ubifs_assert() but while unloading the UBIFS module we don't have the info struct anymore. Therefore replace the asserts by a regular WARN_ON(). Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Use kmalloc_array()Richard Weinberger1-1/+1
Since commit 6da2ec56059c ("treewide: kmalloc() -> kmalloc_array()") we use kmalloc_array() for kmalloc() that computes the length with a multiplication. Cc: Kees Cook <keescook@chromium.org> Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Check data node size before truncateRichard Weinberger1-1/+10
Check whether the size is within bounds before using it. If the size is not correct, abort and dump the bad data node. Cc: Kees Cook <keescook@chromium.org> Cc: Silvio Cesare <silvio.cesare@gmail.com> Cc: stable@vger.kernel.org Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system") Reported-by: Silvio Cesare <silvio.cesare@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15Revert "UBIFS: Fix potential integer overflow in allocation"Richard Weinberger1-3/+2
This reverts commit 353748a359f1821ee934afc579cf04572406b420. It bypassed the linux-mtd review process and fixes the issue not as it should. Cc: Kees Cook <keescook@chromium.org> Cc: Silvio Cesare <silvio.cesare@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Add comment on c->commit_semRichard Weinberger1-0/+1
Every single time I come across that code, I get confused because it looks like a possible dead lock. Help myself by adding a comment. Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: introduce Kconfig symbol for xattr supportStefan Agner6-3/+29
Allow to disable extended attribute support. This aids in reliability testing, especially since some xattr related bugs have surfaced. Also an embedded system might not need it, so this allows for a slightly smaller kernel (about 4KiB). Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: use swap macro in swap_dirty_idxGustavo A. R. Silva1-4/+1
Make use of the swap macro and remove unnecessary variable *t*. This makes the code easier to read and maintain. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: tnc: use monotonic znode timestampArnd Bergmann4-5/+5
The tnc uses get_seconds() based timestamps to check the age of a znode, which has two problems: on 32-bit architectures this may overflow in 2038 or 2106, and it gives incorrect information when the system time is updated using settimeofday(). Using montonic timestamps with ktime_get_seconds() solves both thes problems. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: use timespec64 for inode timestampsArnd Bergmann2-9/+8
Both vfs and the on-disk inode structures can deal with fine-grained timestamps now, so this is the last missing piece to make ubifs y2038-safe on 32-bit architectures. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: xattr: Don't operate on deleted inodesRichard Weinberger1-0/+24
xattr operations can race with unlink and the following assert triggers: UBIFS assert failed in ubifs_jnl_change_xattr at 1606 (pid 6256) Fix this by checking i_nlink before working on the host inode. Cc: <stable@vger.kernel.org> Fixes: 1e51764a3c2a ("UBIFS: add new flash file system") Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: gc: Fix typoRichard Weinberger1-1/+1
UBIFS operates on LEBs, not PEBs. Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Fix memory leak in lprobs self-checkRichard Weinberger1-4/+4
Allocate the buffer after we return early. Otherwise memory is being leaked. Cc: <stable@vger.kernel.org> Fixes: 1e51764a3c2a ("UBIFS: add new flash file system") Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Fix synced_i_size calculation for xattr inodesRichard Weinberger1-0/+5
In ubifs_jnl_update() we sync parent and child inodes to the flash, in case of xattrs, the parent inode (AKA host inode) has a non-zero data_len. Therefore we need to adjust synced_i_size too. This issue was reported by ubifs self tests unter a xattr related work load. UBIFS error (ubi0:0 pid 1896): dbg_check_synced_i_size: ui_size is 4, synced_i_size is 0, but inode is clean UBIFS error (ubi0:0 pid 1896): dbg_check_synced_i_size: i_ino 65, i_mode 0x81a4, i_size 4 Cc: <stable@vger.kernel.org> Fixes: 1e51764a3c2a ("UBIFS: add new flash file system") Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15ubifs: Fix directory size calculation for symlinksRichard Weinberger1-2/+3
We have to account the name of the symlink and not the target length. Fixes: ca7f85be8d6c ("ubifs: Add support for encrypted symlinks") Cc: <stable@vger.kernel.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-15Merge tag 'vfs-timespec64' of ↵Linus Torvalds3-14/+15
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground Pull inode timestamps conversion to timespec64 from Arnd Bergmann: "This is a late set of changes from Deepa Dinamani doing an automated treewide conversion of the inode and iattr structures from 'timespec' to 'timespec64', to push the conversion from the VFS layer into the individual file systems. As Deepa writes: 'The series aims to switch vfs timestamps to use struct timespec64. Currently vfs uses struct timespec, which is not y2038 safe. The series involves the following: 1. Add vfs helper functions for supporting struct timepec64 timestamps. 2. Cast prints of vfs timestamps to avoid warnings after the switch. 3. Simplify code using vfs timestamps so that the actual replacement becomes easy. 4. Convert vfs timestamps to use struct timespec64 using a script. This is a flag day patch. Next steps: 1. Convert APIs that can handle timespec64, instead of converting timestamps at the boundaries. 2. Update internal data structures to avoid timestamp conversions' Thomas Gleixner adds: 'I think there is no point to drag that out for the next merge window. The whole thing needs to be done in one go for the core changes which means that you're going to play that catchup game forever. Let's get over with it towards the end of the merge window'" * tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground: pstore: Remove bogus format string definition vfs: change inode times to use struct timespec64 pstore: Convert internal records to timespec64 udf: Simplify calls to udf_disk_stamp_to_time fs: nfs: get rid of memcpys for inode times ceph: make inode time prints to be long long lustre: Use long long type to print inode time fs: add timespec64_truncate()
2018-06-13treewide: Use array_size() in vmalloc()Kees Cook1-3/+6
The vmalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vmalloc(a * b) with: vmalloc(array_size(a, b)) as well as handling cases of: vmalloc(a * b * c) with: vmalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vmalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(char) * COUNT + COUNT , ...) | vmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vmalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vmalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vmalloc(C1 * C2 * C3, ...) | vmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vmalloc(C1 * C2, ...) | vmalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13treewide: kmalloc() -> kmalloc_array()Kees Cook4-12/+17
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13UBIFS: Fix potential integer overflow in allocationSilvio Cesare1-2/+3
There is potential for the size and len fields in ubifs_data_node to be too large causing either a negative value for the length fields or an integer overflow leading to an incorrect memory allocation. Likewise, when the len field is small, an integer underflow may occur. Signed-off-by: Silvio Cesare <silvio.cesare@gmail.com> Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-11Merge tag 'upstream-4.18-rc1' of git://git.infradead.org/linux-ubifsLinus Torvalds8-22/+13
Pull UBI and UBIFS updates from Richard Weinberger: - the UBI on-disk format header file is now dual licensed - new way to detect Fastmap problems during runtime - bugfix for Fastmap - minor updates for UBIFS (spelling, comments, vm_fault_t, ...) * tag 'upstream-4.18-rc1' of git://git.infradead.org/linux-ubifs: mtd: ubi: Update ubi-media.h to dual license ubi: fastmap: Detect EBA mismatches on-the-fly ubi: fastmap: Check each mapping only once ubi: fastmap: Correctly handle interrupted erasures in EBA ubi: fastmap: Cancel work upon detach ubifs: lpt: Fix wrong pnode number range in comment ubifs: gc: Fix typo ubifs: log: Some spelling fixes ubifs: Spelling fix someting -> something ubifs: journal: Remove wrong comment ubifs: remove set but never used variable ubifs, xattr: remove misguided quota flags fs: ubifs: Adding new return type vm_fault_t
2018-06-07ubifs: lpt: Fix wrong pnode number range in commentSascha Hauer1-1/+1
The comment above pnode_lookup claims the range for the pnode number is from 0 to main_lebs - 1. This is wrong because every pnode has informations about UBIFS_LPT_FANOUT LEBs, thus the corrent range is 0 to to (main_lebs - 1) / UBIFS_LPT_FANOUT. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07ubifs: gc: Fix typoSascha Hauer1-1/+1
"point of view" makes more sense than "point of few". Fix this. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07ubifs: log: Some spelling fixesSascha Hauer1-3/+3
- add missing article - remove misplaced 'it' - s/tress/trees Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07ubifs: Spelling fix someting -> somethingSascha Hauer1-1/+1
Replace "someting" with "something" Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07ubifs: journal: Remove wrong commentSascha Hauer1-3/+2
In the description of reserve_space() it is claimed that write_node() and write_head() unlock the journal head. This is not true and has never been true. All callers of write_node() and write_head() call release_head() themselves. Remove the wrong comment. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07ubifs: remove set but never used variableSascha Hauer2-5/+0
replay_sqnum is set but never used. Remove it. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07ubifs, xattr: remove misguided quota flagsWang Shilong1-1/+1
Originally, Yang Dongsheng added quota support for ubifs, but it turned out upstream won't accept it. Since ubifs don't touch any quota code, S_NOQUOTA flag is misguided here, and currently it is mainly used to avoid recursion for system quota files. Let's make things clearly and remove unnecessary and misguied quota flags here. Reported-by: Rock Lee <rockdotlee@gmail.com> Signed-off-by: Wang Shilong <wshilong@ddn.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-07fs: ubifs: Adding new return type vm_fault_tSouptick Joarder1-7/+4
Use new return type vm_fault_t for page_mkwrite handler. Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-06-06vfs: change inode times to use struct timespec64Deepa Dinamani3-14/+15
struct timespec is not y2038 safe. Transition vfs to use y2038 safe struct timespec64 instead. The change was made with the help of the following cocinelle script. This catches about 80% of the changes. All the header file and logic changes are included in the first 5 rules. The rest are trivial substitutions. I avoid changing any of the function signatures or any other filesystem specific data structures to keep the patch simple for review. The script can be a little shorter by combining different cases. But, this version was sufficient for my usecase. virtual patch @ depends on patch @ identifier now; @@ - struct timespec + struct timespec64 current_time ( ... ) { - struct timespec now = current_kernel_time(); + struct timespec64 now = current_kernel_time64(); ... - return timespec_trunc( + return timespec64_trunc( ... ); } @ depends on patch @ identifier xtime; @@ struct \( iattr \| inode \| kstat \) { ... - struct timespec xtime; + struct timespec64 xtime; ... } @ depends on patch @ identifier t; @@ struct inode_operations { ... int (*update_time) (..., - struct timespec t, + struct timespec64 t, ...); ... } @ depends on patch @ identifier t; identifier fn_update_time =~ "update_time$"; @@ fn_update_time (..., - struct timespec *t, + struct timespec64 *t, ...) { ... } @ depends on patch @ identifier t; @@ lease_get_mtime( ... , - struct timespec *t + struct timespec64 *t ) { ... } @te depends on patch forall@ identifier ts; local idexpression struct inode *inode_node; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn_update_time =~ "update_time$"; identifier fn; expression e, E3; local idexpression struct inode *node1; local idexpression struct inode *node2; local idexpression struct iattr *attr1; local idexpression struct iattr *attr2; local idexpression struct iattr attr; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; @@ ( ( - struct timespec ts; + struct timespec64 ts; | - struct timespec ts = current_time(inode_node); + struct timespec64 ts = current_time(inode_node); ) <+... when != ts ( - timespec_equal(&inode_node->i_xtime, &ts) + timespec64_equal(&inode_node->i_xtime, &ts) | - timespec_equal(&ts, &inode_node->i_xtime) + timespec64_equal(&ts, &inode_node->i_xtime) | - timespec_compare(&inode_node->i_xtime, &ts) + timespec64_compare(&inode_node->i_xtime, &ts) | - timespec_compare(&ts, &inode_node->i_xtime) + timespec64_compare(&ts, &inode_node->i_xtime) | ts = current_time(e) | fn_update_time(..., &ts,...) | inode_node->i_xtime = ts | node1->i_xtime = ts | ts = inode_node->i_xtime | <+... attr1->ia_xtime ...+> = ts | ts = attr1->ia_xtime | ts.tv_sec | ts.tv_nsec | btrfs_set_stack_timespec_sec(..., ts.tv_sec) | btrfs_set_stack_timespec_nsec(..., ts.tv_nsec) | - ts = timespec64_to_timespec( + ts = ... -) | - ts = ktime_to_timespec( + ts = ktime_to_timespec64( ...) | - ts = E3 + ts = timespec_to_timespec64(E3) | - ktime_get_real_ts(&ts) + ktime_get_real_ts64(&ts) | fn(..., - ts + timespec64_to_timespec(ts) ,...) ) ...+> ( <... when != ts - return ts; + return timespec64_to_timespec(ts); ...> ) | - timespec_equal(&node1->i_xtime1, &node2->i_xtime2) + timespec64_equal(&node1->i_xtime2, &node2->i_xtime2) | - timespec_equal(&node1->i_xtime1, &attr2->ia_xtime2) + timespec64_equal(&node1->i_xtime2, &attr2->ia_xtime2) | - timespec_compare(&node1->i_xtime1, &node2->i_xtime2) + timespec64_compare(&node1->i_xtime1, &node2->i_xtime2) | node1->i_xtime1 = - timespec_trunc(attr1->ia_xtime1, + timespec64_trunc(attr1->ia_xtime1, ...) | - attr1->ia_xtime1 = timespec_trunc(attr2->ia_xtime2, + attr1->ia_xtime1 = timespec64_trunc(attr2->ia_xtime2, ...) | - ktime_get_real_ts(&attr1->ia_xtime1) + ktime_get_real_ts64(&attr1->ia_xtime1) | - ktime_get_real_ts(&attr.ia_xtime1) + ktime_get_real_ts64(&attr.ia_xtime1) ) @ depends on patch @ struct inode *node; struct iattr *attr; identifier fn; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; expression e; @@ ( - fn(node->i_xtime); + fn(timespec64_to_timespec(node->i_xtime)); | fn(..., - node->i_xtime); + timespec64_to_timespec(node->i_xtime)); | - e = fn(attr->ia_xtime); + e = fn(timespec64_to_timespec(attr->ia_xtime)); ) @ depends on patch forall @ struct inode *node; struct iattr *attr; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); fn (..., - &attr->ia_xtime, + &ts, ...); ) ...+> } @ depends on patch forall @ struct inode *node; struct iattr *attr; struct kstat *stat; identifier ia_xtime =~ "^ia_[acm]time$"; identifier i_xtime =~ "^i_[acm]time$"; identifier xtime =~ "^[acm]time$"; identifier fn, ret; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime); + &ts); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime); + &ts); | + ts = timespec64_to_timespec(stat->xtime); ret = fn (..., - &stat->xtime); + &ts); ) ...+> } @ depends on patch @ struct inode *node; struct inode *node2; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier i_xtime3 =~ "^i_[acm]time$"; struct iattr *attrp; struct iattr *attrp2; struct iattr attr ; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; struct kstat *stat; struct kstat stat1; struct timespec64 ts; identifier xtime =~ "^[acmb]time$"; expression e; @@ ( ( node->i_xtime2 \| attrp->ia_xtime2 \| attr.ia_xtime2 \) = node->i_xtime1 ; | node->i_xtime2 = \( node2->i_xtime1 \| timespec64_trunc(...) \); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | stat->xtime = node2->i_xtime1; | stat1.xtime = node2->i_xtime1; | ( node->i_xtime2 \| attrp->ia_xtime2 \) = attrp->ia_xtime1 ; | ( attrp->ia_xtime1 \| attr.ia_xtime1 \) = attrp2->ia_xtime2; | - e = node->i_xtime1; + e = timespec64_to_timespec( node->i_xtime1 ); | - e = attrp->ia_xtime1; + e = timespec64_to_timespec( attrp->ia_xtime1 ); | node->i_xtime1 = current_time(...); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | - node->i_xtime1 = e; + node->i_xtime1 = timespec_to_timespec64(e); ) Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: <anton@tuxera.com> Cc: <balbi@kernel.org> Cc: <bfields@fieldses.org> Cc: <darrick.wong@oracle.com> Cc: <dhowells@redhat.com> Cc: <dsterba@suse.com> Cc: <dwmw2@infradead.org> Cc: <hch@lst.de> Cc: <hirofumi@mail.parknet.co.jp> Cc: <hubcap@omnibond.com> Cc: <jack@suse.com> Cc: <jaegeuk@kernel.org> Cc: <jaharkes@cs.cmu.edu> Cc: <jslaby@suse.com> Cc: <keescook@chromium.org> Cc: <mark@fasheh.com> Cc: <miklos@szeredi.hu> Cc: <nico@linaro.org> Cc: <reiserfs-devel@vger.kernel.org> Cc: <richard@nod.at> Cc: <sage@redhat.com> Cc: <sfrench@samba.org> Cc: <swhiteho@redhat.com> Cc: <tj@kernel.org> Cc: <trond.myklebust@primarydata.com> Cc: <tytso@mit.edu> Cc: <viro@zeniv.linux.org.uk>
2018-06-06Merge tag 'fscrypt_for_linus' of ↵Linus Torvalds1-9/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Add bunch of cleanups, and add support for the Speck128/256 algorithms. Yes, Speck is contrversial, but the intention is to use them only for the lowest end Android devices, where the alternative *really* is no encryption at all for data stored at rest" * tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: fscrypt: log the crypto algorithm implementations fscrypt: add Speck128/256 support fscrypt: only derive the needed portion of the key fscrypt: separate key lookup from key derivation fscrypt: use a common logging function fscrypt: remove internal key size constants fscrypt: remove unnecessary check for non-logon key type fscrypt: make fscrypt_operations.max_namelen an integer fscrypt: drop empty name check from fname_decrypt() fscrypt: drop max_namelen check from fname_decrypt() fscrypt: don't special-case EOPNOTSUPP from fscrypt_get_encryption_info() fscrypt: don't clear flags on crypto transform fscrypt: remove stale comment from fscrypt_d_revalidate() fscrypt: remove error messages for skcipher_request_alloc() failure fscrypt: remove unnecessary NULL check when allocating skcipher fscrypt: clean up after fscrypt_prepare_lookup() conversions fs, fscrypt: only define ->s_cop when FS_ENCRYPTION is enabled fscrypt: use unbound workqueue for decryption
2018-05-22ubifs_lookup: use d_splice_alias()Al Viro1-28/+15
code is simpler that way Acked-by: Richard Weinberger <richard@nod.at> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-20fscrypt: make fscrypt_operations.max_namelen an integerEric Biggers1-9/+1
Now ->max_namelen() is only called to limit the filename length when adding NUL padding, and only for real filenames -- not symlink targets. It also didn't give the correct length for symlink targets anyway since it forgot to subtract 'sizeof(struct fscrypt_symlink_data)'. Thus, change ->max_namelen from a function to a simple 'unsigned int' that gives the filesystem's maximum filename length. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>