diff options
| author | Pierre Riteau <pierre@stackhpc.com> | 2025-02-13 23:36:10 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-02-15 09:07:09 -0800 |
| commit | 071ed42cff4fcdd89025d966d48eabef59913bf2 (patch) | |
| tree | 15e4beca2e5938509346b29852741d23fb05c804 /net/sched | |
| parent | 9593172d93b9f91c362baec4643003dc29802929 (diff) | |
net/sched: cls_api: fix error handling causing NULL dereference
tcf_exts_miss_cookie_base_alloc() calls xa_alloc_cyclic() which can
return 1 if the allocation succeeded after wrapping. This was treated as
an error, with value 1 returned to caller tcf_exts_init_ex() which sets
exts->actions to NULL and returns 1 to caller fl_change().
fl_change() treats err == 1 as success, calling tcf_exts_validate_ex()
which calls tcf_action_init() with exts->actions as argument, where it
is dereferenced.
Example trace:
BUG: kernel NULL pointer dereference, address: 0000000000000000
CPU: 114 PID: 16151 Comm: handler114 Kdump: loaded Not tainted 5.14.0-503.16.1.el9_5.x86_64 #1
RIP: 0010:tcf_action_init+0x1f8/0x2c0
Call Trace:
tcf_action_init+0x1f8/0x2c0
tcf_exts_validate_ex+0x175/0x190
fl_change+0x537/0x1120 [cls_flower]
Fixes: 80cd22c35c90 ("net/sched: cls_api: Support hardware miss to tc action")
Signed-off-by: Pierre Riteau <pierre@stackhpc.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/20250213223610.320278-1-pierre@stackhpc.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/cls_api.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 8e47e5355be6..4f648af8cfaa 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -97,7 +97,7 @@ tcf_exts_miss_cookie_base_alloc(struct tcf_exts *exts, struct tcf_proto *tp, err = xa_alloc_cyclic(&tcf_exts_miss_cookies_xa, &n->miss_cookie_base, n, xa_limit_32b, &next, GFP_KERNEL); - if (err) + if (err < 0) goto err_xa_alloc; exts->miss_cookie_node = n; |