e7711f15ed
commit 11b73313c12403f617b47752db0ab3deef201af7 upstream.
In blamed commit, I missed that get_dist_table() was allocating
memory using GFP_KERNEL, and acquiring qdisc lock to perform
the swap of newly allocated table with current one.
In this patch, get_dist_table() is allocating memory and
copy user data before we acquire the qdisc lock.
Then we perform swap operations while being protected by the lock.
Note that after this patch netem_change() no longer can do partial changes.
If an error is returned, qdisc conf is left unchanged.
Fixes: 2174a08db80d ("sch_netem: acquire qdisc lock in netem_change()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230622181503.2327695-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.