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ext4: fix race writing to an inline_data file while its xattrs are ch… #2
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…anging commit a54c4613dac1500b40e4ab55199f7c51f028e848 upstream. The location of the system.data extended attribute can change whenever xattr_sem is not taken. So we need to recalculate the i_inline_off field since it mgiht have changed between ext4_write_begin() and ext4_write_end(). This means that caching i_inline_off is probably not helpful, so in the long run we should probably get rid of it and shrink the in-memory ext4 inode slightly, but let's fix the race the simple way for now. Cc: [email protected] Fixes: f19d587 ("ext4: add normal write support for inline data") Reported-by: [email protected] Signed-off-by: Theodore Ts'o <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
…server platform, as that has had an array overrun issue identified. It is believed that no one is using this code. Signed-off-by: Russell King <[email protected]>
In __htab_map_lookup_and_delete_batch(), hash buckets are iterated over to count the number of elements in each bucket (bucket_size). If bucket_size is large enough, the multiplication to calculate kvmalloc() size could overflow, resulting in out-of-bounds write as reported by KASAN: [...] [ 104.986052] BUG: KASAN: vmalloc-out-of-bounds in __htab_map_lookup_and_delete_batch+0x5ce/0xb60 [ 104.986489] Write of size 4194224 at addr ffffc9010503be70 by task crash/112 [ 104.986889] [ 104.987193] CPU: 0 PID: 112 Comm: crash Not tainted 5.14.0-rc4 #13 [ 104.987552] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 [ 104.988104] Call Trace: [ 104.988410] dump_stack_lvl+0x34/0x44 [ 104.988706] print_address_description.constprop.0+0x21/0x140 [ 104.988991] ? __htab_map_lookup_and_delete_batch+0x5ce/0xb60 [ 104.989327] ? __htab_map_lookup_and_delete_batch+0x5ce/0xb60 [ 104.989622] kasan_report.cold+0x7f/0x11b [ 104.989881] ? __htab_map_lookup_and_delete_batch+0x5ce/0xb60 [ 104.990239] kasan_check_range+0x17c/0x1e0 [ 104.990467] memcpy+0x39/0x60 [ 104.990670] __htab_map_lookup_and_delete_batch+0x5ce/0xb60 [ 104.990982] ? __wake_up_common+0x4d/0x230 [ 104.991256] ? htab_of_map_free+0x130/0x130 [ 104.991541] bpf_map_do_batch+0x1fb/0x220 [...] In hashtable, if the elements' keys have the same jhash() value, the elements will be put into the same bucket. By putting a lot of elements into a single bucket, the value of bucket_size can be increased to trigger the integer overflow. Triggering the overflow is possible for both callers with CAP_SYS_ADMIN and callers without CAP_SYS_ADMIN. It will be trivial for a caller with CAP_SYS_ADMIN to intentionally reach this overflow by enabling BPF_F_ZERO_SEED. As this flag will set the random seed passed to jhash() to 0, it will be easy for the caller to prepare keys which will be hashed into the same value, and thus put all the elements into the same bucket. If the caller does not have CAP_SYS_ADMIN, BPF_F_ZERO_SEED cannot be used. However, it will be still technically possible to trigger the overflow, by guessing the random seed value passed to jhash() (32bit) and repeating the attempt to trigger the overflow. In this case, the probability to trigger the overflow will be low and will take a very long time. Fix the integer overflow by calling kvmalloc_array() instead of kvmalloc() to allocate memory. Fixes: 0579963 ("bpf: Add batch ops to all htab bpf map") Signed-off-by: Tatsuhiko Yasumatsu <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
Create set scheduler aggregator node and move for VSIs into respective scheduler node. Max children per aggregator node is 64. There are two types of aggregator node(s) created. 1. dedicated node for PF and _CTRL VSIs 2. dedicated node(s) for VFs. As part of reset and rebuild, aggregator nodes are recreated and VSIs are moved to respective aggregator node. Having related VSIs in respective tree avoid starvation between PF and VF w.r.t Tx bandwidth. Co-developed-by: Tarun Singh <[email protected]> Signed-off-by: Tarun Singh <[email protected]> Co-developed-by: Victor Raj <[email protected]> Signed-off-by: Victor Raj <[email protected]> Co-developed-by: Anirudh Venkataramanan <[email protected]> Signed-off-by: Anirudh Venkataramanan <[email protected]> Signed-off-by: Kiran Patil <[email protected]> Tested-by: Tony Brelinski <[email protected]> Signed-off-by: Tony Nguyen <[email protected]>
In case the file cannot be opened with O_NOATIME because of lack of capabilities, then clear O_NOATIME instead of failing. Remove WARN_ON(), since it would now trigger if O_NOATIME was cleared. Noticed by Amir Goldstein. Signed-off-by: Miklos Szeredi <[email protected]>
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…anging
commit a54c4613dac1500b40e4ab55199f7c51f028e848 upstream.
The location of the system.data extended attribute can change whenever
xattr_sem is not taken. So we need to recalculate the i_inline_off
field since it mgiht have changed between ext4_write_begin() and
ext4_write_end().
This means that caching i_inline_off is probably not helpful, so in
the long run we should probably get rid of it and shrink the in-memory
ext4 inode slightly, but let's fix the race the simple way for now.
Cc: [email protected]
Fixes: f19d587 ("ext4: add normal write support for inline data")
Reported-by: [email protected]
Signed-off-by: Theodore Ts'o [email protected]
Signed-off-by: Greg Kroah-Hartman [email protected]