6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Artem Chernyshev artem.chernyshev@red-soft.ru
[ Upstream commit 76201b5979768500bca362871db66d77cb4c225e ]
Passing a sufficient amount of imix entries leads to invalid access to the pkt_dev->imix_entries array because of the incorrect boundary check.
UBSAN: array-index-out-of-bounds in net/core/pktgen.c:874:24 index 20 is out of range for type 'imix_pkt [20]' CPU: 2 PID: 1210 Comm: bash Not tainted 6.10.0-rc1 #121 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Call Trace: <TASK> dump_stack_lvl lib/dump_stack.c:117 __ubsan_handle_out_of_bounds lib/ubsan.c:429 get_imix_entries net/core/pktgen.c:874 pktgen_if_write net/core/pktgen.c:1063 pde_write fs/proc/inode.c:334 proc_reg_write fs/proc/inode.c:346 vfs_write fs/read_write.c:593 ksys_write fs/read_write.c:644 do_syscall_64 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe arch/x86/entry/entry_64.S:130
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 52a62f8603f9 ("pktgen: Parse internet mix (imix) input") Signed-off-by: Artem Chernyshev artem.chernyshev@red-soft.ru [ fp: allow to fill the array completely; minor changelog cleanup ] Signed-off-by: Fedor Pchelkin pchelkin@ispras.ru Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/pktgen.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 34f68ef74b8f2..b6db4910359bb 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -851,6 +851,9 @@ static ssize_t get_imix_entries(const char __user *buffer, unsigned long weight; unsigned long size;
+ if (pkt_dev->n_imix_entries >= MAX_IMIX_ENTRIES) + return -E2BIG; + len = num_arg(&buffer[i], max_digits, &size); if (len < 0) return len; @@ -880,9 +883,6 @@ static ssize_t get_imix_entries(const char __user *buffer,
i++; pkt_dev->n_imix_entries++; - - if (pkt_dev->n_imix_entries > MAX_IMIX_ENTRIES) - return -E2BIG; } while (c == ' ');
return i;