From: Felix Riemann felix.riemann@sma.de
stable inclusion from stable-v4.19.296 commit b17d81b94d24834d0ee038c6e216752f43b67cc9 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I95ATV CVE: CVE-2023-52578
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 9b55d3f0a69af649c62cbc2633e6d695bb3cc583 ]
When converting net_device_stats to rtnl_link_stats64 sign extension is triggered on ILP32 machines as 6c1c509778 changed the previous "ulong -> u64" conversion to "long -> u64" by accessing the net_device_stats fields through a (signed) atomic_long_t.
This causes for example the received bytes counter to jump to 16EiB after having received 2^31 bytes. Casting the atomic value to "unsigned long" beforehand converting it into u64 avoids this.
Fixes: 6c1c5097781f ("net: add atomic_long_t to net_device_stats fields") Signed-off-by: Felix Riemann felix.riemann@sma.de Reviewed-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zhengchao Shao shaozhengchao@huawei.com --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/dev.c b/net/core/dev.c index c7f03f382851..a9aca8971a59 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -9036,7 +9036,7 @@ void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); for (i = 0; i < n; i++) - dst[i] = atomic_long_read(&src[i]); + dst[i] = (unsigned long)atomic_long_read(&src[i]); /* zero out counters that only exist in rtnl_link_stats64 */ memset((char *)stats64 + n * sizeof(u64), 0, sizeof(*stats64) - n * sizeof(u64));