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In commit b212921b13bd ("elf: don't use MAP_FIXED_NOREPLACE for elf
executable mappings") we still leave MAP_FIXED_NOREPLACE in place for
load_elf_interp.
Unfortunately, this will cause kernel to fail to start with:
1 (init): Uhuuh, elf segment at 00003ffff7ffd000 requested but the memory is mapped already
Failed to execute /init (error -17)
The reason is that the elf interpreter (ld.so) has overlapping segments.
readelf -l ld-2.31.so
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000
0x000000000002c94c 0x000000000002c94c R E 0x10000
LOAD 0x000000000002dae0 0x000000000003dae0 0x000000000003dae0
0x00000000000021e8 0x0000000000002320 RW 0x10000
LOAD 0x000000000002fe00 0x000000000003fe00 0x000000000003fe00
0x00000000000011ac 0x0000000000001328 RW 0x10000
The reason for this problem is the same as described in commit
ad55eac74f20 ("elf: enforce MAP_FIXED on overlaying elf segments").
Not only executable binaries, elf interpreters (e.g. ld.so) can have
overlapping elf segments, so we better drop MAP_FIXED_NOREPLACE and go
back to MAP_FIXED in load_elf_interp.
Fixes: 4ed28639519c ("fs, elf: drop MAP_FIXED usage from elf_map")
Cc: <stable@vger.kernel.org> # v4.19
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Chen Jingwen <chenjingwen6@huawei.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull ext4 fixes from Ted Ts'o:
"Fix a number of ext4 bugs in fast_commit, inline data, and delayed
allocation.
Also fix error handling code paths in ext4_dx_readdir() and
ext4_fill_super().
Finally, avoid a grabbing a journal head in the delayed allocation
write in the common cases where we are overwriting a pre-existing
block or appending to an inode"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: recheck buffer uptodate bit under buffer lock
ext4: fix potential infinite loop in ext4_dx_readdir()
ext4: flush s_error_work before journal destroy in ext4_fill_super
ext4: fix loff_t overflow in ext4_max_bitmap_size()
ext4: fix reserved space counter leakage
ext4: limit the number of blocks in one ADD_RANGE TLV
ext4: enforce buffer head state assertion in ext4_da_map_blocks
ext4: remove extent cache entries when truncating inline data
ext4: drop unnecessary journal handle in delalloc write
ext4: factor out write end code of inline file
ext4: correct the error path of ext4_write_inline_data_end()
ext4: check and update i_disksize properly
ext4: add error checking to ext4_ext_replay_set_iblocks()
The objtool warning that the kvm instruction emulation code triggered
wasn't very useful:
arch/x86/kvm/emulate.o: warning: objtool: __ex_table+0x4: don't know how to handle reloc symbol type: kvm_fastop_exception
in that it helpfully tells you which symbol name it had trouble figuring
out the relocation for, but it doesn't actually say what the unknown
symbol type was that triggered it all.
In this case it was because of missing type information (type 0, aka
STT_NOTYPE), but on the whole it really should just have printed that
out as part of the message.
Because if this warning triggers, that's very much the first thing you
want to know - why did reloc2sec_off() return failure for that symbol?
So rather than just saying you can't handle some type of symbol without
saying what the type _was_, just print out the type number too.
Fixes: 24ff65257375 ("objtool: Teach get_alt_entry() about more relocation types")
Link: https://lore.kernel.org/lkml/CAHk-=wiZwq-0LknKhXN4M+T8jbxn_2i9mcKpO+OaBSSq_Eh7tg@mail.gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 8e33fadf945a ("ext4: remove an unnecessary if statement in
__ext4_get_inode_loc()") forget to recheck buffer's uptodate bit again
under buffer lock, which may overwrite the buffer if someone else have
already brought it uptodate and changed it.
Fixes: 8e33fadf945a ("ext4: remove an unnecessary if statement in __ext4_get_inode_loc()")
Cc: stable@kernel.org
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210910080316.70421-1-yi.zhang@huawei.com
The recent change to make objtool aware of more symbol relocation types
(commit 24ff65257375: "objtool: Teach get_alt_entry() about more
relocation types") also added another check, and resulted in this
objtool warning when building kvm on x86:
arch/x86/kvm/emulate.o: warning: objtool: __ex_table+0x4: don't know how to handle reloc symbol type: kvm_fastop_exception
The reason seems to be that kvm_fastop_exception() is marked as a global
symbol, which causes the relocation to ke kept around for objtool. And
at the same time, the kvm_fastop_exception definition (which is done as
an inline asm statement) doesn't actually set the type of the global,
which then makes objtool unhappy.
The minimal fix is to just not mark kvm_fastop_exception as being a
global symbol. It's only used in that one compilation unit anyway, so
it was always pointless. That's how all the other local exception table
labels are done.
I'm not entirely happy about the kinds of games that the kvm code plays
with doing its own exception handling, and the fact that it confused
objtool is most definitely a symptom of the code being a bit too subtle
and ad-hoc. But at least this trivial one-liner makes objtool no longer
upset about what is going on.
Fixes: 24ff65257375 ("objtool: Teach get_alt_entry() about more relocation types")
Link: https://lore.kernel.org/lkml/CAHk-=wiZwq-0LknKhXN4M+T8jbxn_2i9mcKpO+OaBSSq_Eh7tg@mail.gmail.com/
Cc: Borislav Petkov <bp@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When ext4_htree_fill_tree() fails, ext4_dx_readdir() can run into an
infinite loop since if info->last_pos != ctx->pos this will reset the
directory scan and reread the failing entry. For example:
1. a dx_dir which has 3 block, block 0 as dx_root block, block 1/2 as
leaf block which own the ext4_dir_entry_2
2. block 1 read ok and call_filldir which will fill the dirent and update
the ctx->pos
3. block 2 read fail, but we has already fill some dirent, so we will
return back to userspace will a positive return val(see ksys_getdents64)
4. the second ext4_dx_readdir will reset the world since info->last_pos
!= ctx->pos, and will also init the curr_hash which pos to block 1
5. So we will read block1 too, and once block2 still read fail, we can
only fill one dirent because the hash of the entry in block1(besides
the last one) won't greater than curr_hash
6. this time, we forget update last_pos too since the read for block2
will fail, and since we has got the one entry, ksys_getdents64 can
return success
7. Latter we will trapped in a loop with step 4~6
Cc: stable@kernel.org
Signed-off-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210914111415.3921954-1-yangerkun@huawei.com
Pull char/misc driver fixes from Greg KH:
"Here are some small misc driver fixes for 5.15-rc4. They are in two
"groups":
- ipack driver fixes for issues found by Johan Hovold
- interconnect driver fixes for reported problems
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
ipack: ipoctal: fix module reference leak
ipack: ipoctal: fix missing allocation-failure check
ipack: ipoctal: fix tty-registration error handling
ipack: ipoctal: fix tty registration race
ipack: ipoctal: fix stack information leak
interconnect: qcom: sdm660: Add missing a2noc qos clocks
dt-bindings: interconnect: sdm660: Add missing a2noc qos clocks
interconnect: qcom: sdm660: Correct NOC_QOS_PRIORITY shift and mask
interconnect: qcom: sdm660: Fix id of slv_cnoc_mnoc_cfg
The error path in ext4_fill_super forget to flush s_error_work before
journal destroy, and it may trigger the follow bug since
flush_stashed_error_work can run concurrently with journal destroy
without any protection for sbi->s_journal.
[32031.740193] EXT4-fs (loop66): get root inode failed
[32031.740484] EXT4-fs (loop66): mount failed
[32031.759805] ------------[ cut here ]------------
[32031.759807] kernel BUG at fs/jbd2/transaction.c:373!
[32031.760075] invalid opcode: 0000 [#1] SMP PTI
[32031.760336] CPU: 5 PID: 1029268 Comm: kworker/5:1 Kdump: loaded
4.18.0
[32031.765112] Call Trace:
[32031.765375] ? __switch_to_asm+0x35/0x70
[32031.765635] ? __switch_to_asm+0x41/0x70
[32031.765893] ? __switch_to_asm+0x35/0x70
[32031.766148] ? __switch_to_asm+0x41/0x70
[32031.766405] ? _cond_resched+0x15/0x40
[32031.766665] jbd2__journal_start+0xf1/0x1f0 [jbd2]
[32031.766934] jbd2_journal_start+0x19/0x20 [jbd2]
[32031.767218] flush_stashed_error_work+0x30/0x90 [ext4]
[32031.767487] process_one_work+0x195/0x390
[32031.767747] worker_thread+0x30/0x390
[32031.768007] ? process_one_work+0x390/0x390
[32031.768265] kthread+0x10d/0x130
[32031.768521] ? kthread_flush_work_fn+0x10/0x10
[32031.768778] ret_from_fork+0x35/0x40
static int start_this_handle(...)
BUG_ON(journal->j_flags & JBD2_UNMOUNT); <---- Trigger this
Besides, after we enable fast commit, ext4_fc_replay can add work to
s_error_work but return success, so the latter journal destroy in
ext4_load_journal can trigger this problem too.
Fix this problem with two steps:
1. Call ext4_commit_super directly in ext4_handle_error for the case
that called from ext4_fc_replay
2. Since it's hard to pair the init and flush for s_error_work, we'd
better add a extras flush_work before journal destroy in
ext4_fill_super
Besides, this patch will call ext4_commit_super in ext4_handle_error for
any nojournal case too. But it seems safe since the reason we call
schedule_work was that we should save error info to sb through journal
if available. Conversely, for the nojournal case, it seems useless delay
commit superblock to s_error_work.
Fixes: c92dc856848f ("ext4: defer saving error info from atomic context")
Fixes: 2d01ddc86606 ("ext4: save error info to sb through journal if available")
Cc: stable@kernel.org
Signed-off-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210924093917.1953239-1-yangerkun@huawei.com
Merge tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Here are some driver core and kernfs fixes for reported issues for
5.15-rc4. These fixes include:
- kernfs positive dentry bugfix
- debugfs_create_file_size error path fix
- cpumask sysfs file bugfix to preserve the user/kernel abi (has been
reported multiple times.)
- devlink fixes for mdiobus devices as reported by the subsystem
maintainers.
Also included in here are some devlink debugging changes to make it
easier for people to report problems when asked. They have already
helped with the mdiobus and other subsystems reporting issues.
All of these have been linux-next for a while with no reported issues"
* tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
kernfs: also call kernfs_set_rev() for positive dentry
driver core: Add debug logs when fwnode links are added/deleted
driver core: Create __fwnode_link_del() helper function
driver core: Set deferred probe reason when deferred by driver core
net: mdiobus: Set FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD for mdiobus parents
driver core: fw_devlink: Add support for FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD
driver core: fw_devlink: Improve handling of cyclic dependencies
cpumask: Omit terminating null byte in cpumap_print_{list,bitmask}_to_buf
debugfs: debugfs_create_file_size(): use IS_ERR to check for error
A reference to the carrier module was taken on every open but was only
released once when the final reference to the tty struct was dropped.
Fix this by taking the module reference and initialising the tty driver
data when installing the tty.
Fixes: 82a82340bab6 ("ipoctal: get carrier driver to avoid rmmod")
Cc: stable@vger.kernel.org # 3.18
Cc: Federico Vaga <federico.vaga@cern.ch>
Acked-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210917114622.5412-6-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We should use unsigned long long rather than loff_t to avoid
overflow in ext4_max_bitmap_size() for comparison before returning.
w/o this patch sbi->s_bitmap_maxbytes was becoming a negative
value due to overflow of upper_limit (with has_huge_files as true)
Below is a quick test to trigger it on a 64KB pagesize system.
sudo mkfs.ext4 -b 65536 -O ^has_extents,^64bit /dev/loop2
sudo mount /dev/loop2 /mnt
sudo echo "hello" > /mnt/hello -> This will error out with
"echo: write error: File too large"
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/594f409e2c543e90fd836b78188dfa5c575065ba.1622867594.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull scheduler fixes from Borislav Petkov:
- Tell the compiler to always inline is_percpu_thread()
- Make sure tunable_scaling buffer is null-terminated after an update
in sysfs
- Fix LTP named regression due to cgroup list ordering
* tag 'sched_urgent_for_v5.15_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Always inline is_percpu_thread()
sched/fair: Null terminate buffer when updating tunable_scaling
sched/fair: Add ancestors of unthrottled undecayed cfs_rq
A KMSAN warning is reported by Alexander Potapenko:
BUG: KMSAN: uninit-value in kernfs_dop_revalidate+0x61f/0x840
fs/kernfs/dir.c:1053
kernfs_dop_revalidate+0x61f/0x840 fs/kernfs/dir.c:1053
d_revalidate fs/namei.c:854
lookup_dcache fs/namei.c:1522
__lookup_hash+0x3a6/0x590 fs/namei.c:1543
filename_create+0x312/0x7c0 fs/namei.c:3657
do_mkdirat+0x103/0x930 fs/namei.c:3900
__do_sys_mkdir fs/namei.c:3931
__se_sys_mkdir fs/namei.c:3929
__x64_sys_mkdir+0xda/0x120 fs/namei.c:3929
do_syscall_x64 arch/x86/entry/common.c:51
It seems a positive dentry in kernfs becomes a negative dentry directly
through d_delete() in vfs_rmdir(). dentry->d_time is uninitialized
when accessing it in kernfs_dop_revalidate(), because it is only
initialized when created as negative dentry in kernfs_iop_lookup().
The problem can be reproduced by the following command:
cd /sys/fs/cgroup/pids && mkdir hi && stat hi && rmdir hi && stat hi
A simple fixes seems to be initializing d->d_time for positive dentry
in kernfs_iop_lookup() as well. The downside is the negative dentry
will be revalidated again after it becomes negative in d_delete(),
because the revison of its parent must have been increased due to
its removal.
Alternative solution is implement .d_iput for kernfs, and assign d_time
for the newly-generated negative dentry in it. But we may need to
take kernfs_rwsem to protect again the concurrent kernfs_link_sibling()
on the parent directory, it is a little over-killing. Now the simple
fix is chosen.
Link: https://marc.info/?l=linux-fsdevel&m=163249838610499
Fixes: c7e7c04274b1 ("kernfs: use VFS negative dentry caching")
Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20210928140750.1274441-1-houtao1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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