]> git.ipfire.org Git - thirdparty/linux.git/commit
mm/vmalloc: do not trigger BUG() on BH disabled context
authorUladzislau Rezki (Sony) <urezki@gmail.com>
Fri, 15 May 2026 15:30:09 +0000 (17:30 +0200)
committerAndrew Morton <akpm@linux-foundation.org>
Fri, 22 May 2026 02:06:13 +0000 (19:06 -0700)
commit04aa71da5f35aacdc9ae9cb5150947daa624f641
treec90f50c45a98dc9531a596608dd2ee5b135a138d
parentf0af98ff6b3077278974a460becbd05bbc710e60
mm/vmalloc: do not trigger BUG() on BH disabled context

__get_vm_area_node() currently triggers a BUG() if in_interrupt() returns
true.  However, in_interrupt() also reports true when BH are disabled.

The bridge code can call rhashtable_lookup_insert_fast() with bottom
halves disabled:

__vlan_add()
 -> br_fdb_add_local()
  spin_lock_bh(&br->hash_lock); <-- Disable BH
   -> fdb_add_local()
    -> fdb_create()
     -> rhashtable_lookup_insert_fast()
      -> kvmalloc()
       -> vmalloc()
        -> __get_vm_area_node()
         -> BUG_ON(in_interrupt())
  spin_unlock_bh(&br->hash_lock)

this triggers the BUG() despite the caller not being in NMI or
hard IRQ context.

Replace the in_interrupt() check with in_nmi() || in_hardirq().

Link: https://lore.kernel.org/20260515153009.2296191-1-urezki@gmail.com
Fixes: c6307674ed82 ("mm: kvmalloc: add non-blocking support for vmalloc")
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Ido Schimmel <idosch@nvidia.com>
Reported-by: syzbot+8b12fc6e0fb139765b58@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/69ff8c7c.050a0220.1036b8.000b.GAE@google.com/
Reviewed-by: Baoquan He <baoquan.he@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm/vmalloc.c