The EAL hotplug multi-process messaging uses a fixed-size buffer (EAL_DEV_MP_DEV_ARGS_MAX_LEN, 128 bytes) for device arguments. When devargs exceeds this limit, strlcpy silently truncates the string. This causes secondary processes to receive incomplete devargs during hotplug re-add, leading to failed port re-initialization.
For example, a MANA PCI device with 6 mac= arguments: mac=AA:BB:CC:DD:EE:01,mac=AA:BB:CC:DD:EE:02, mac=AA:BB:CC:DD:EE:03,mac=AA:BB:CC:DD:EE:04, mac=AA:BB:CC:DD:EE:05,mac=AA:BB:CC:DD:EE:06 produces a 131-byte devargs string that gets silently truncated to 127 bytes, losing the last MAC address. Return -E2BIG from rte_dev_probe() and rte_dev_remove() when devargs would be truncated, instead of silently corrupting data. Signed-off-by: Long Li <[email protected]> --- lib/eal/common/eal_common_dev.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/lib/eal/common/eal_common_dev.c b/lib/eal/common/eal_common_dev.c index 7185de0cb9..de24d14d28 100644 --- a/lib/eal/common/eal_common_dev.c +++ b/lib/eal/common/eal_common_dev.c @@ -250,6 +250,11 @@ rte_dev_probe(const char *devargs) memset(&req, 0, sizeof(req)); req.t = EAL_DEV_REQ_TYPE_ATTACH; + if (strlen(devargs) >= EAL_DEV_MP_DEV_ARGS_MAX_LEN) { + EAL_LOG(ERR, "devargs truncated (len %zu, max %d)", + strlen(devargs), EAL_DEV_MP_DEV_ARGS_MAX_LEN); + return -E2BIG; + } strlcpy(req.devargs, devargs, EAL_DEV_MP_DEV_ARGS_MAX_LEN); if (rte_eal_process_type() != RTE_PROC_PRIMARY) { @@ -397,6 +402,12 @@ rte_dev_remove(struct rte_device *dev) memset(&req, 0, sizeof(req)); req.t = EAL_DEV_REQ_TYPE_DETACH; + if (strlen(devargs) >= EAL_DEV_MP_DEV_ARGS_MAX_LEN) { + EAL_LOG(ERR, "devargs truncated (len %zu, max %d)", + strlen(devargs), EAL_DEV_MP_DEV_ARGS_MAX_LEN); + free(devargs); + return -E2BIG; + } strlcpy(req.devargs, devargs, EAL_DEV_MP_DEV_ARGS_MAX_LEN); free(devargs); -- 2.43.0
